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TTM8000 - Roithner Lasertechnik

1. 54 Power connector cable et Hebe bte er tert tod ioo hb qc apt eee abbr Ld dapes 54 External display connector cable optional uuusersssnnnnnennesnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn 54 Parallel lO CODnectOr he rt Het dte oet betae badge ir ep hodieque tese ve 55 Analog lO corifigctor cipe Cit e e eie nip ee addet ep eri 55 SIGMal COMNECOLS e RT 55 EIE 55 Trouble Shooting 5 Hrn Pe era PCR ret eer ure ud e etme ie e e eee e 56 Setting up a Network interface under eee nennen nennen nenne nennen nennen 58 Firewalls orn EN ewm 59 TTM8000 2 60 Introduction The 8 channel Time Tagging Module TTM8000 can be used to measure the timing of digital events rising and or falling edges with high to extremely high resolution depending on the chosen measurement mode on up to 8 digital signals for a wide range of logic families What is a TTM8000 A TTM8000 is an electronic device that can be used to measure the timing of electronic pulses on up to eight external digital inputs with high resolution While the actual technical solution is slightly different we can think of the TTM8000 as a counter that is incremented at a very high constant rate forming a clock with high resol
2. ov osov j Just like with TTMOCntrl we first need to select a TTM8000 module to work with and then connect to that module In the digitial input output section we can use the DirOut Dirln radio buttons to define each pin as either input or output For a given measurement setup each pin is usually defined to be either only an input or only an output Switching the direction of a pin in the middle of a measurement is a rare occurrence and accidental switches are potentially dangerous if two outputs are set to drive against each other Thus TTMUserlO provides the checkbox Lock Dir that locks the direction of all digital I O pins 39 60 TTM8000 For each digital I O pin we also have a checkbox that defines the value of the pin when used as output and a text giving the actual current value If the pin is configured as input changing the output value does not have any direct effect of the hardware however it might still be useful to configure the value that will become effective as soon as the pin is configured as output Furthermore TTMUserlO shows the voltage that are currently active on the analog inputs For each analog input pin you can select the measurement mode Unipolar 0 4 095V or Bipolar 2 047V Finally TTMUserlO allows setting the voltages of the 4 analog outputs in the range of 4 095V TTM8000 40 60 Provided Command Line Applications ttmcmd Configure Control Timetagging Modules TTM
3. ROITHNER LASERT ecHNIK TTM8000 Time Tagging Module with 8 Channels Release 4 4 2 April 16 2015 1 60 TTM8000 Table of Contents Introduction ee D N 3 Mhbatis a T TMOOUQD ii pu NI Mra m erc id 3 What s the use of a 8000 4 Fess 5 TTM8000 BET LUE H 6 Front Panel Eletrients td ist etie cce 6 Back Ranel Elements tn Hrn ta teet atten pis 7 Getting Started with the TTM8000 eisian anok ARA 9 Setting up the Network Interface ssssssssssseeeeneeeeneeeeenn nemen nennen 9 Setting m E 10 Booting the 0 ne es rn REDE mu Eve e d 11 Selecting an optimal measurement 4 12 Sample Application Jitter 14 Sample Application Correlation Measurement ssssssssssssssssssssseseseeeee eene nennen 24 Sample Application Event Clustering Bursts sssssssssssssssssssseeeeee nennen nennen 33 Sample Application Using Multiple TTM8000
4. false externclockinfreq lt Freq gt Hz kHz MHz externclockinlevel Level mV V The TTM8000 contains a clock synthesizer that will generate the reference clock for the TTM8000 it can either be driven from an internal crystal or from an external reference clock running at 10 20 40 or 80MHz Besides generating the clock needed for the operation of the TTM8000 the clock synthesizer can also generate an external output clock at 1 2 5 10 20 40 or 80MHz Note that any settings made with set only remain active until the next power cycle See config clocksynth set led info1 info2 info3 A B C off red yellow orange green set led info1 info2 info3 A B red green on off Turn the Info LEDs on the TTM8000 on off or select their color to provide visual feedback to the user set digitalioout Mask Value The TTM8000 contains 8 digital I O Ports that can be used to control measure external signals Use DigitallOOut to set the level of selected output pins 43 60 TTM8000 set digitaliodir lt Mask gt Value The TTM8000 contains 8 digital I O Ports that be used to control measure external signals Use DigitallODir to configure selected pins as Input 1 or Output 0 get digitalioin lt RepeatCnt gt lt MilliDelay gt The TTM8000 contains 8 digital I O Ports that can be used to control measure external signals Use DigitallOIn to display the st
5. or the TTMCmd commands pulsegen start stop to configure the pulse generator TTM8000 8 60 Getting Started with the TTM8000 Setting up the Network Interface Configure a Ethernet Interface on your computer to operate in network 192 168 1 0 24 Note The TTM8000 does not support routing of Ethernet packets Both the TTM8000 and your computer must always be in the same subnet You can later configure the subnet you wish to use but this initial configuration must be done in subnet 192 168 1 0 24 Note IPv6 is not supported You are strongly encouraged to use Gigabit Ethernet rather than a 100Mbit Ethernet Interface since 100Mbit Ethernet will reduce the number of events that can be processed to about 2 5MEvents s Furthermore you should activate Jumbo Frames on your computer if supported by your Ethernet interface and make sure that your operating system permits your receiving application to use large input network buffers for the timetag UDP socket Directly connect the Ethernet Interface of your computer to the Ethernet Interface of the TTM8000 using a CAT 6 patch cable Note TTM8000 uses UDP IP to transfer timetag data Since UDP only offers unreliable service it is strongly recommended that you use a dedicated direct connection between the TTM8000 and your computer rather than mixing TTM8000 traffic with other traffic on a switch router that might lose packets Network Tuning for Linux If you are not sure how to set u
6. out FMT Output Format FMT Output Format b binary Useful for writing to file for later processing or filling of a pipe for processing by another application expanded binary Like b however packed measurements are unpacked to flat measurements r raw hex Simply dump each timetag as a single hex number without splitting for fields h pretty hex Dump each field channel slope time of each timetag as a hex number t text Write each field channel slope time in a suitable format Additional Text depending on Data Format T lt FormatString gt Write each event into a single line as ASCII text that contains a copy of the FormatString where each occurrence of the macros CHN SLOPE and TIME is substituted with suitable contents S statistics Do not print a line for each individual Make a frequency table statistic and print that at the end of the measurement Note If you wish to receive data from the net you will usually use either the d or the t option If you specified a specific local port when starting the TTM8000 you should use d to receive data from this specific port If you have not specified the local port when starting the TTM8000 you should use the t option and specify the IP address of the TTM8000 board you wish to use any INADDR ANY to have ttmcnvt to search for a TTM8000 board on the net Some samples uses are Read timetags from the net and write them to stdout in human readable
7. s u 7 a 8 2 8 HHH Hi P amp gt 4 v Ticks H Ti 1790 Local Delay Mean 6537 87ps Std Dev 2214 98ps SampleSize Global Delay Mean 6578 53ps Std Dev 2182 83ps SampleSize 27 005 Config Log While this is already much better and the peak is already quite easy to estimate we shall refine our Min Max Range once more and look at the range of 6ns 8ns to Delay Histogram Log Scale a 5 2 gt m Stop Event Stop 5 Rising Edge Local Delay Mean 7500 13ps Std Dev 314 58ps SampleSize 1 152 vv Start Event Stop 2 Rising Edge His Ticks Bin Size Full Min Max ime Range Ti Global Delay Mean 7505 73ps Std Dev 305 97ps SampleSize 15 188 Config Log 28 60 TTM8000 After letting the histogram rebuild itself for a while we can get a fairly accurate reading for both the center of the peak corresponding to the time delays between the signal sources at about 7 6ns and the width of the peak corresponding to the joint jitter of the signal sources of about 0 5ns around this center Thus we know that for pairs of correlated events on channels 2 and 5 the event on channel 5 arrive at the TTM8000 about 7 6ns earlier than the event on channel 2 and that there i
8. 0 0 ns Single Event Filter Eliminate Events whose nearest neighbor is more than 5000 0 ns 5 away Forward Store Data Forward Store Data before or after applying the Deadtime Offset Adjustment and or Single Event Filter Address 27 0 0 o 0503 LA UDP Host IP Address 127 0 0 1 w Port 10503 5 File homellieger Time Tags Out dat Data Analysis Show Event Counters Create Delay Histogram Show Pair Coinc Show Multi Coinc Create Cluster Histogram Save Contig Load Config Now we can open the pair coincidence display by clicking Show Pair Coinc in the TTMViewer s Data Source window 29 60 TTM8000 Single Counts amp 2 Channel Coincidences Stop 3 Stop 5 0 302 451 Singles 12 011 681 201 000 7 982 603 1134 42 639 0 0 0 0 0 0 0 0 0 0 Coincidence Window Width Config Log Start Log Reset Counters The pair coincidence display shows how many rising or falling auto detected events arrive on each channel and how many coincidences there were between any events on even numbered and odd numbered channels Each field consists of two numbers The top number shows the number of events correlations occurred in the last second while the bottom number shows the total number since start of the measurement In an ideal world without timing jitter correlated events would after adjustment of the offset that we
9. 7 last second distribution blue and the histogram for the total distribution red are plotted on top of each other While this is convenient if we want to observe the difference between the current situation and the long term average it can make it difficult to evaluate a single plot We can therefore use the checkboxes next to the line color symbols to disable one or the other diagram Usually the histogram will count all events that come along Sometimes however we are only interested in events that occur within a certain time range Thus it is possible to define a lower upper bound for events that shall be counted All events outside this range will be discarded When looking at streams of events that contain lots of different timing intervals it is sometimes not useful to count the occurrences of each individual interval by itself Instead it is better to group neighboring durations and form bigger bins when computing the histogram It is therefore possible to define the size of each histogram bin as multiple of TTM8000 ticks Obviously using bigger bins reduces the resolution of the recorded data and thus degrades the precision Note that the CPU load created by creating a histogram depends on the number of bins that are used If you have a signal that has a very wide range of used bins and lots of samples per second you can easily overload the CPU of your PC The update intervals will then become longer and TTMViewer will eventually appear
10. Both approaches have their advantages If you specify a port here the receiver never needs to detect the TTM8000 board and can fully concentrate on data processing However if the receiver specifies itself as target the network connection between TTM8000 and receiver application is initiated by the receiver and should cause less trouble if a network firewall is active on the PC Furthermore the selection of an available UDP port is left to the operating system thus avoiding collisions between multiple receiver applications wishing to receive data from different TTM8000s If we specify data targets explicitly collisions must be avoided by careful manual assignment of UDP ports If we wanted to record the timetags for later processing we could also have them sent to TTMCntrl and have them written to a file Note that TTMCntrl will never overwrite an existing file If it finds the filename already used it will append a counter to the filename MyTimetags dat becomes MyTimetags 2 dat or if that is already used too MyTimetags 3 dat up to MyTimetags 100 dat In addition to this TTMCntrl supports macros in filenames and will substitute TIME DATE and COUNT with appropriate contents Note that macro names are case sensitive We have now successfully set up the data generation side of our sample application and can move on to the data processing evaluation side 15 60 TTM8000 Start the application TTMViewer We will receive data directly f
11. Each network packet can contain a limited amount of data Every Ethernet adapter can transfer packets with 1500Byte payload but most Gigabit adapters can also handle larger Jumbo Frames that can transfer large amounts of data with less overhead For optimal performance it is therefore recommended that you configure the MTU Max Transfer Unit of the PCs network adapter to at least 8000Byte If you process the data on the same machine that you use for TTMCmd the TTMLib can automatically detect the optimal packet size If you use two different machines for TTMCmd and your timetag processing you must inform the TTM8000 of the optimal packet size set timeout lt Timeout gt us ms s Hz kHz Delay until Data Idle The TTM8000 sends measurement data to the PC every time a complete network packet of data is available If the data rate is very low or completely stopped waiting for a completely filled packet might take too long Thus the TTM8000 will send a partially filled packet if data is available and no packet has been sent for lt Timeout gt set userdata lt UserData gt Every Timetag Packet contains a 16 bit word of User Data that can be used for arbitrary application specific purposes e g to identify a specific measurement configuration Its value is not used interpreted in any way by the TTM8000 et set clocksynth useexternclockout true false externclockoutfreq Freq Hz kHz MHz useexternclockin true
12. If this is not possible for you and other devices are attached to that network too then please check with your local system administrator to see what IP addresses are already in use for these devices and are thus not available for eth1 In particular if you want to use the TTM8000 from several host PCs be sure to pick a different IP address for each host PC For this demonstration we shall assume that there are no additional devices and we shall pick 192 168 1 143 sudo ifconfig ethl 192 168 1 143 netmask 255 255 255 0 To obtain optimal performance you should try to increase the maximal packet size permitted on the network The recommended MTU Max Transfer Unit size is 9000 byte however such large frames jumbo frames are not supported by all network interfaces If the following command fails on your system try again with 8000 6000 or 4000 byte If that fails too your network interface probably does not support jumbo frames The TTM8000 will still work however the CPU load on the TTM8000 and the host PC will be higher sudo ifconfig ethl mtu 9000 Now we can enable our newly configured network interface sudo ifconfig ethl up To check that everything worked out fine we use ifconfig ethl and get something along the lines of ethl i RX 0 errors 0 dropped 0 0 frame 0 TX packets 16 errors 0 dropped 0 overruns 0 carrier 0 collisions 0 txqueuelen 1000 bytes 0 0 0 B TX bytes 3091 3 0 KiB Interrupt 250 Base addre
13. Rising Edge Falling Edge Count Freq Hz Count Freq Hz Stop 1 9 446 457 200 000 0 Stop 2 Stop 3 Stop 4 Stop 5 Stop 6 Stop 7 Stop 8 ER CEN EX EX EA lt lt S 8 lt lt lt amp Event Frequency History Use Common Scale for all Lines Reset Graph Config Log Start Log Reset Counters In the Event Counter window we see the total number of timetags received as well as the number of timetags received within the last second for each channel as text and graphically In the following screenshot we can easily spot locations where network packets were lost due to external CPU overload 19 60 TTM8000 Event Counter TTM8000 Signal Event Counter Frequency Rising Edge Falling Edge Count Freq Hz Count Freq Hz Stop 1 34 340 007 199 999 0 Stop 2 0 Stop 3 Stop 4 Stop 5 Stop 6 Stop 7 m lt lt lt lt lt lt lt lt Stop 8 Event Frequency History Y Use Common Scale for all Lines ResetGraph Config Log Start Log Reset Counters If we have several sources that send events at different frequencies we can also compare their relative event rates However if one event source is much faster than another source the diagram for the slower source can be compressed into a few or even a single pixel and become unreadable Thus there is a option to scale each curve independently to use the full height of t
14. The TTM8000 requires a power supply of 12V DC 2A DC Power LED The Power LED shows the status of the power supply Green External power supply and internal voltages Red There is a power supply however some of the voltages are out of spec Off Power supply missing Display optional For some applications the TTM8000 will not be a stand alone device but it will be part of a bigger system In such situations it is useful to be able to have the buttons and status LEDs accessible from the outside of the bigger system separate from the TTM8000s location The Display connector allows such a remote display to be connected This is a optional feature that may or may be not be installed on your system Ethernet The TTM8000 requires a Ethernet connection to transfer commands and measurement results Using a Gigabit Ethernet connection is highly recommended since 100Mbit s Ethernet Fast Ethernet will severely limit the number of events that can be processed Clock Signals e Ref Clock In The TTM8000 contains an internal reference clock however it can also use an external reference clock of 10 20 40 or 80 MHz This can be useful to keep several TTM8000s and or other devices in perfect synchronization Use TTMLib Library function TTMCntrl c SetExternClockConfig or the TTMCmd commands set config clocksynth to select the speed of the external reference clock Ref Clock Out The TTM8000 board can generate a refere
15. we shall demonstrate yet another feature of TTMMerge we shall force an automatic stop after 10 seconds of processing We can do so by editing Step 4 Automatic limitation of Runtime in the ttmmerge cmd file Just remove the comment from the limitation there Note that these limitations measure the time or amount of events that ttmmerge reads input data If we set a time limit and no data arrives in this time e g because the event source is not started processing will stop without having processed any data Also if we have a filter in place a lot of input data might still result in no output data because non of the data matched There is currently no way to specify the time actually spent for processing data or the requested amount of output data Remember to save your changes Now start TTMMerge again TTMMerge will run for 10 seconds as specified in Step 4 of the merge cmd script file and after these 10 seconds we have a text file that lists all events that were part of a triple coincidence We can look at this in a text editor and or feed it into a custom application for further processing TTM8000 38 60 Using the User I O Pins of the TTM8000 The TTM8000 module features 8 digital I O input output pins 4 analog input pins and 4 analog output pins that are available for application specific use e g monitoring controlling external devices The 8 digital I O pins use LVTTL signals 0 3 3V and can individually be configured as i
16. 2 5 10 20 40 or 80MHz Settings made with config clocksynth remain valid even if the board is power cycled Thus a TTM8000 board whose clock synthesizer has been properly configured can be used as reference clock by other devices even if the TTM8000 itself is not actively initialized used by a user application 45 60 TTM8000 echo Text Print a line of text date Print the current date time sleep msleep usleep Time s sec ms msec us usec m min h hour Delay script execution Time is a floating point quantity that is optionally followed by a unit If no unit is provided sleep assumes seconds msleep assumes milliseconds and usleep assumes microseconds def lt VarName gt Value Assign a value to a variable Once a variable is defined it can be used as parameter in any command using the Syntax VarName Note however that this is a simple single token for single token substitution You can not use a single variable to provide a string of parameters or a complete command Variables can be defined with different strictness as either plain or protected Plain variables are defined using the operator They can be redefined using another protected or unprotected def statement Protected variables are defined using either the or the operator Attempts to redefine a protected variable using the or will not change the value of a protected variable It is however possi
17. 8 or 7 conductors The shield must be connected on both sides The layout of the cable is symmetric View from solder side of cable connector Pin 1 3V3 Pin 2 SPI 2 DOUT Pin 3 SPI 2 DIN Pin 4 SPI 2 CLK Pin 5 SPI 2 CS1 Pin 6 SPI 2 CS2 not used can stay unconnected Pin 7 DONE Pin 8 GND TTM8000 54 60 Parallel IO connector Use only 10 pin IDC female connector with 2 54 mm contact spacing e g Harting 09185106813 Pin 1 Digital IO 0 Pin2 Digital lO 4 Pin3 Digital IO 1 Pin4 Digital IO 5 Pin5 Digital lO 2 Pin 6 Digital IO 6 7 Digital lO 3 Pin8 Digital lO 7 Pin 9 10 GND me He H H H Be g Analog IO connector Use only 16 pin IDC female connector with 2 54 mm contact spacing e g Harting 09185166813 Pin 2 4 6 8 10 12 14 16 GND Pin 1 Analog Out 0 Pin 3 Analog Out 1 Pin 5 Analog Out 2 Pin 7 Analog Out 3 Pin9 Analog In O Pin 11 Analog In 1 Pin 13 Analog In 2 Pin 15 Analog In 3 Signal connectors Use only SMB type plugs female contact with 50 O Impedance for connecting cables to the coaxial inputs outputs Warnings During operation the case of TTM 8000 will get hot Be careful when touching the device Do not prevent free air circulation around the TTM 8000 Do not block the ventilation holes Do not expose the devi
18. TTMViewers Timing Histogram feature to display the relative offset between the two channels that were derived from a single Source using the active signal splitter Looking at the histogram for a few seconds we can easily see that the timing of the two channels is stable there is a constant mean offset between the two channels that does change over time i e there is no drift between the two locked reference clocks Furthermore we can see that the width of the timing histogram is unfortunately a little wider than the histogram that we would have obtained had we measured all channels on a single TTM8000 board since the local PLLs of each TTM8000 oscillate around the optimal frequency Using an high quality signal generator Stanford Research CG635 to create synchronous pulses the timing jitter increased from 60ps standard deviation when both copies of the pulse were measured on the same TTM8000 to 130ps when using two different TTM8000s We can use the mean value that we see in TTMViewer s Delay Histogram to correct the offset of one of the channels so that events that originate from the same source are also recorded with the same timestamp To do so we shall simply open ttmmerge cmd in our favorite text editor again and modify the offset in Step 2 Define the Channel Offsets After starting TTMMerge again we can verify that the mean time offset between channel 1 2 and 2 5 is now close to zero even so they arrived on two different boards ov
19. Windows Firewall has been disabled check if you or your local system administrator have installed additional security tools e g Virus Scanners Network Filters a Firewall other then the one shipped with Windows Since there is a multitude of such tools we can not provide a guide on how to configure disable them to get the TTM8000 Software to work Maybe they have a dedicated item in the Control Panel maybe there is a item in the Windows Security Center maybe there is a administration application in the Start Menu or there might be an entry in the property sheet of each network interface e g Check Point SecuRemote We strongly recommend that you seek advice from your local system administrator No measurement data is received Is the Buffer LED lit and does the Activity LED of the network interface flash If it is then data is produced and lost on the way to your application e g TTMViewer It the LEDs are permanently off then no data is produced to begin with and the data acquisition logic is probably misconfigured Assuming that data is produced but does not reach your application or TTMViewer Is your Network Firewall active Turn it off or use Receiver Req as Data Destination in TTMCntrl and choose the appropriate TTM8000 module Data Source in TTMViewer Can you detect the network packets with a Ethernet network sniffer e g WireShark Are you sure the target IP address and UDP port configured in TTMCntrl matches the IP addre
20. changing from yellow to green left to right Bootloader Loading PowerPC application All LEDs dark PowerPC Application startup Link LED on PowerPC Application ready Green Gigabit Ethernet detected Yellow 100Mbit 1OMBit Ethernet detected Red Missing Network If the LEDs change from yellow to green in a center to edge fashion rather than left to right then the TTM8000 Board is running in Secure Mode This means that the primary server software has been detected as damaged e g after a firmware update gone awry and the backup software has been booted The board is fully functional however you should update the primary software If the board does not boot at all the primary server software might be damaged in a way that is not recognized by the bootloader You can enforce booting of the backup software by holding the button during power up Keep the button pressed until booting is completed By default the TTM8000 module has an IP address of 192 168 1 60 with a subnet mask of 255 255 255 0 You can change this later by using the TTMCmd application see command config network ipaddr netmaskc Confirm that your network is working fine by issuing a ping 192 168 1 60 11 60 TTM8000 Selecting an optimal measurement mode The TTM8000 can measure data in 4 different modes I G R M Mode that each have advantages drawbacks The following guide shall help you select the best measurement mode for
21. channel no multicopy It is also possible to drop an input channel that is not required at the moment e g to reduce network load storage requirements lt ChannelMapping gt has the following syntax channelmap lt SrcChn gt gt lt DestChn gt lt SrcChn gt gt lt DestChn gt lt SrcChn gt and lt DestChn gt usually follow the Syntax of lt BoardID gt lt StopID gt where lt BoardID gt is a number in the Range 1 16 and lt StopID gt is a number in the range 1 8 However there is a special lt StopID gt of which means all Stops from 1 8 together The special lt SrcChn gt of means all stops from all boards while the special lt DestChn gt of X means drop lt CoincFilter gt is optional indicates how many events must occur within a coincidence window to be considered of interest The Syntax for lt CoincFilter gt is mincoinccount lt MinCnt gt maxcoinccount lt MaxCnt gt coincwindow lt Time gt Examples Send the merged data stream to a network port in flat multi board format dataout send flat net 192 168 1 56 10007 Send Data in single board packed format to a given UDP Port where e g TTMViewer can pick up the data Since we are using single board format we need to map all interesting channels to the virtual board 1 Thus we shall first mark all channels as drop an then map the interesting ones to selected Stops of board1 Note that we map two input channels to a single output channel Thus the
22. configured in the Data Source dialog occur at exactly the same time Since we live in the real world with timing jitter we need to allow a Coincidence Window Width that defines how far away two events may be to be considered to have happened at the same time measured from the first event in the coincidence group to the last event of the coincidence group A good choice for this distance would be the distance from the lower end of the peak to the upper end of the peak in the delay histogram or twice the distance from the top of the peak to either end assuming we have a more or less symmetric peak If we assume that our sources are not extremely stable we might want to make our coincidence window a little wider to allow for drift of the delays during the course of the measurements Of course this means that we add false positives to our coincidence detection however you will reduce the number of missed coincidences In our example we have chosen a coincidence window of 1ns even so the peak in our histogram was much thinner Note The fact that we are only showing events and odd vs even correlations and not all any to any correlations for both rising and falling events is an implementation detail of TTMViewer that was chosen to keep the size of the window down It is not a technical limitation of the TTM8000 or TTMLib In fact TTMViewer actually computes all any to any correlations and just limits the display to rising events odd vs even If odd v
23. for this Thus we can adjust maxsockbuf using 9 60 TTM8000 the command sudo sysctl w kern ipc maxsockbuf 37752832 for 32MByte max network buffer 4MByte housekeeping overhead 4KByte rounding 36MByte Note The maximal acceptable value for maxsockbuf varies depending on the version of OS X Newer versions seem to implement an upper limit of 4MByte which is also their default value While it would be nice to have a little more security margin when measuring very fast event sequences with TTM8000 4 MByte will usually be sufficient too Don t worry too much about this limitation Setting up Qt Qt is a popular library for building portable User Interfaces It is available from http www qt io for Linux Windows Apple OS X and several other operating systems The TTM8000 comes with two sets of sample applications TTMCmd and TTMCnvt are command line and or script based applications that do not require Qt TTMCntrl and TTMViewer are GUI applications that are based on Qt and require the Qt4 libraries to run If you only want to run the provided executables you just need to make the Qt libraries accessible to TTMCntrl and TTMViewer The required files are part of the TTM8000 software package and are located in the TTM8000 qt folder for Linux Windows and OS X Setting up Qt on Linux On Linux desktop system Qt is usually preinstalled so no additional effort is needed on your part If this should indeed not be true on your system lib
24. or big endian as used e g on PowerPC or 680x0 based systems byte order Timetags can only be processed by the receiving host if they are available in the hosts native byte order Timetags that come with the wrong byte order must have their bytes reordered first which is automatically done by TTMLib so you won t see the difference in the data however this conversion requires processing time on the host CPU that could be spent for better purposes if the timetags already arrive with the correct byte order Note The byte order setting applies only to timetag data It does not affect any other control structures set slope start stop1 stop2 stop8 rise rising fall falling 0 off disable 1 on enable Enable Disable Events Slopes set startsrc extern intern pulsegen The TTM8000 Start input can either be triggered by an external signal or with the signal generated by the built in pulse generator see command pulsegen below TTM8000 42 60 set signallevel start stop1 stop2 stop8 stop all Level mV V The TTM8000 supports a wide range of input logic levels High and Low signal levels are distinguished by comparing the input level to a threshold level Voltages greater than the threshold level are considered as High while smaller voltages are considered Low For most logic families a value in the middle of the nominal High and Low level will work best e g 1 5V for 3V TTL
25. signal source and the TTM8000 introduces its own unknown delay that is hopefully more or less stable for some time and will not fluctuate too wildly Thus we need to discover the difference of these delays Note We have no absolute timing reference and thus can not discover the absolute length of any of the delays however the difference of delays is sufficient for our purposes We thus click on Create Delay Histogram to create a histogram We select a Start Event of Stop 2 Rising Edge and a Stop Event of Stop 5 Rising Edge Since we do not know which channel will have the shorter delay we can not say which channel will come first and thus enable Unordered processing of the events i e each event on one channel is measured with respect the the nearest event that can be either following or preceding no strict order from the other channel Note that TTMViewer searches only for the nearest match Thus we need to make sure that the timing difference between the two channels is significantly less that the signal rate of each channel If we assume that our signal sources produce less than 2MEvents s for an average 500ns between any two events and assume that the timing difference is less than 100ns corresponding to 20m of cable or fiber we can be fairly certain that we corresponding events are grouped properly Since we are going to perform a statistical measurement we can tolerate some errors TTM8000 26 60 Since w
26. the noise is not correlated to our measurement interval and our measurement interval is much longer than any correlation time of the noise the noise on the different samples will hopefully cancel out partially at least and we can obtain a measurement that contains much less noise Obviously this benefit comes at the price that we have to wait longer for each measurement and that the CPU of the TTM is loaded with additional work Thus we should only use this feature if we really need it and remember to turn if off once no longer needed adjust Adjust parameters for the current measurement The adjust command works like set however the adjustment takes place at immediately rather than with the start of the next measurement Note that not all parameters can be adjusted while a measurement is already in progress adjust slope start stop1 stop2 stop8 rise rising fall falling 0 off disable 1 on enable Enable Disable Events Slopes adjust signallevel start stop1 stop2 stop8 stop all Level mV V The TTM8000 supports a wide range of input logic levels High and Low signal levels are distinguished by comparing the input level to a threshold level Voltages greater than the threshold level are considered as High while smaller voltages are considered Low For most logic families a value in the middle of the nominal High and Low level will work best e g 1 5V for 3V TTL Do not
27. use the nominal High level of your logic family as reference level SignalLevel controls the reference voltage used for the Start and Stop1 Stop8 inputs Since every input uses a reference voltage of its own it is possible to measure signals from different logic families at the same time Valid Range 4 096V adjust clocklevel Level mV V The TTM8000 supports a wide range of input logic levels High and Low signal levels are distinguished by comparing the input level to a threshold level Voltages greater than the threshold level are considered as High while smaller voltages are considered Low For most logic families a value in the middle of the nominal High and Low level will work best e g 1 5V for 3V TTL Do not use the nominal High level of your logic family as reference level ClockLevel controls the reference voltage used for the external clock Valid Range 4 096V TTM8000 44 60 measurement start auto manual Start the Measurement If you are using continuous I Mode with the Start pulse generated by the built in pulse generator you can choose if you want the pulse generator to automatically generate the Start event or if you prefer to start the pulse generator manually Unless you want to perform calibration measurements with the built in pulse generator you should always let the pulse generator automatically generate the Start event for you default measurement stop Stop the Measurement p
28. your application 1 Do you need to measure continuous sequences of events longer than at most 65 where the timing of each event is measured on the same timescale making it possible to determine the time difference between any two events using a simple subtraction or do your events always occur in groups with a clearly defined Start event that is closely max 65 followed by possibly zero Stop events that shall be measured with respect to this Start event Every Start event defines its own timescale It is not possible to determine the relative offsets between two such timescales If you need continuous measurements then continue your selection process at step 2 otherwise go to step 3 2 You should use Continuous I Mode This lets you measure rising and or falling edges on up to eight channels simultaneously with a resolution of 82 3045ps 1 12 15GHz Continuous I Mode comes in two flavors Non Compressed and Compressed In Non Compressed mode each recorded event is stored in a 64 bit data element 3bit channel 1bit slope 60bit timetag 29 82 3ps 1098days This format is very easy to interpret for any application that displays the events however it is also fairly bulky Since all data must be transferred via Ethernet and depending on your network hardware and configuration MTU size Ethernet is limited to about 100MByte s you can only transfer 12 MEvents s Compressed I Mode uses the same basic
29. 00 to the Ref Clock In of the third TTM8000 and thus form a daisy chain of synchronized clocks Alternately we could use an active signal splitter that takes its input from the Ref Clock Out of the first TTM8000 and whose outputs are connected to the Ref Clock In of all other TTM8000s Do NOT connect the output of the signal splitter to the Ref Clock In of the first TTM8000 since this would create a loop and the first TTM8000 would be confused if it should use the external or internal clock Using a active signal splitter will for more than two boards will probably produce better results since the jitter of the reference clock increases with every additional link of the daisy chain but this does of course incur extra hardware costs We shall use the second cable to connect the Start Out connector from the back of the first TTM8000 to the Start Input on the front of the Second TTM8000 This cable will be needed to start the two TTM8000 at almost the same time Of course there will be some delay as the Start signal travels from the first TTM8000 through various drivers to the connectors through the cable to the second TTM8000 and through some more drivers in the TTM8000 until it is actually processed however for a given setup this time is practically constant and can be compensated with a fixed offset that is added to the results For a setup with just two TTM8000 this is easiest and best solution for distributing the start signal It we had more tha
30. 1 60 TTM8000 Custom Applications TTMCmd TTMCnvt TTMMerge and TTMCntrl TTMViewer TTMUserlO are intended as a demonstrations of possible use cases not as all in one solutions suitable for every purpose You will probably need to write your own application to match your specific measurement requirements However since the sources of all demo applications are provided with TTM8000 you can get a convenient head start by using their code as basis of your own development For a description of the API Application Programming Interface please check out the HTML documentation TTM Application development on Windows If you are using Microsoft Windows as your operating system you will probably use Microsoft Visual Studio as your development tools Microsoft offers a Express Edition of Visual Studio as a free download at https www visualstudio com and Professional Ultimate and Enterprise Editions as increasingly powerful and expensive commercial solutions If you just want to modify the provided command line tool TTMCmd TTMCnvt TTMMerge or create your own command line tools using the Express Edition is fine If you want to use Qt based GUls you will need to use at least the Professional Edition of Visual Studio to get a complete integration of Qt development into the Visual Studio IDE For Qt development you also need the Qt development tools that be downloaded free of charge from http www qt io download open source TTMOC
31. 17 60 TTM8000 TTMViewer comes to life We see that TTMViewer automatically detected the type of measurement we selected in TTMCntrl and starts receiving data If the TTMViewer does not come to life there are basically three different reasons why this is so Either the TTM8000 does not produce any measurement data at all or the TTM8000 creates measurement data but does not send it anywhere or the data is created and sent but it is lost on the net We can use the Buffer LED to check if the TTM8000 creates any data If the LED is off no data is created and we need to check if the pulse generator actually creates pulses Suggested configuration 200kHz 0 Volt Low 3 Volt High Level and these pulses are actually fed into one of the TTM8000 s Stop inputs NOT the leftmost Start Input The factory installed jumper at the Stop input should be in place and your pulse generator should be set to drive 50Ohm Be sure that you actually started the measurement in TTMCntrl We can use the Network Activity LED at the rear of the TTM8000 to check if the TTM8000 sends any data If the LED is permanently lit or flashing wildly then measurement data is sent If it is off or just flashing occasionally then no measurement data is sent and we see the effect of other traffic on the network If in doubt temporarily disconnect the Stop input and see if this brings the network activity to a stop too If no network data is sent the TTM8000 might not know wher
32. 8000 device try clicking the Re Scan Net button If this does not help try using ping 192 168 1 60 assuming you have not yet changed the TTM8000s IP address to determine if you have a working network connection Time Tagging Control Center Time Tagging Module Module IP Addr 192 168 1 60 TTM8000 Re Scan Net Connect ud Measurement Meas Mode I Mode 8 Chn cont 82 3ps 64bit compressed Byte Order Little Endian e g Intel x86 Alpha Signal Input Level Signal Delay Compensation TTL amp 1 5V 1 50 r3 V Advanced Config Active Signal Edges Start Stop1 Stop2 Stop3 Stopd StopS Stop6 Stop Stop8 Rising Edge Y Y Y Y Falling Edge Data Destination UDP Host IP Addr Receiver Req Port 10502 H File homedieger Time Tags dat Received OKByte OKByte s Load TTM8000 14 60 Select a Module IP Addr of 192 168 1 60 and click the Connect button to connect the GUI to the TTM8000 device Now choose a Measurement Mode of I Mode 8 Chn cont 82 3ps 64 bit compressed and a Byte Order of Little Endian e g Intel x86 Alpha The Signal Input Level determines the threshold voltage that distinguishes low high signal levels Since the signal from our signal generator is set to operate using signal levels of OV and 3V a threshold of 1 5V provides a nice distinction between low and high Since 1 5V is a
33. Cmd is a command line application that can be used to configure control TTM8000 devices functionally similar to the graphical TTMCntrl application It can either execute a command script recommended for complex operations or a list of commands provided directly on the command line Supported command line options are t ttm8 IP Port Target Time Tagging Module Default Auto 10501 n ttmnet IP Port Time Tagging Module Subnet Default Auto 10501 Used for searching for Boards C cntrl IP Port Local Cntrl Port Default Auto Auto d data IP Port Target Data Port Default Auto Auto f script FILE Execute Commands from a Script File i interactive Execute Command read from Standard Input X cmd CMD Execute Verbatim Commands l list List all Boards D def NAME VALUE Assign a Value to a Name v verbose Show Internal Information V version Show Version Information Note The command script files start and stop cmd are part of the TTM8000 distribution in TTM8000 demoapps bin Scripts and show how to start and stop a measurement They are well documented and are recommended for use as template for your own scripts A single instance of TTMCmd can control multiple TTM8000 modules This is demonstrated in mstart cmd and mstop cmd Some examples command lines for using ttmcmd List all TTM8000 devices that are available on the network ttmcmd l Execute the script start cm
34. D gt usually referes to a single Stop input of a single TTM8000 board e g 2 6 but you can also refer to all Stops of a board by using a e g 2 Time is specified as decimal numbers with a suitable unit ms us ns ps Example deadtime 2 5 3ns deadtime 4 2 7ns Sometimes we want to process a potentially infinite stream of data Sometimes however we want to automatically stop processing after enough data has been processed How much processing is enough can be defined in terms of time or in terms of processed input data Stop after Cnt sec min hours Byte KByte MByte Events Automatically stop after Cnt seconds minutes hours have passed Cnt Byte KByte MByte of input data has been processed or lt Cnt gt Events have been processed Example stop after 10s stop after 100000 Events Now that we have collected all the data and produced a single sorted stream of non duplicated timetags we need to create output streams where these timetags will be sent to There can be multiple output streams where each stream has its own filter for coincidences its own output format and its own destination Thus we can feed multiple receivers with timetags matching their own needs e g send a selection of channels to TTMViewer via network for direct visual control and write the complete timetags to file for later processing When sending data via network we can choose among 4 binary format flat multiboard for
35. Do not use the nominal High level of your logic family as reference level SignalLevel controls the reference voltage used for the Start and Stop1 Stop8 inputs Since every input uses a reference voltage of its own it is possible to measure signals from different logic families at the same time Valid Range 4 096V et set signaldelay stop1 stop2 stop8 stop all Delay ticks ps ns us ms s The cables used to connect the signal sources to the TTM8000 inputs introduce a delay of about 50ps cm cable length To compensate for the differences in delays introduced by these cables the TTM8000 can add an offset to every measurement so that events are sorted by the order in which they occurred not the order in which they arrived at the TTM8000 Valid Range 125Ticks Resolution 1Tick The length of a tick depends on the chosen measurement mode see set mode above et set datatarget lt IP Addr gt lt Port gt The TTM8000 sends the obtained timetags via Ethernet to a PC for further processing storage etc The IP address and UDP port to which the data shall be sent is defined by DataTarget Note that TTM8000 does NOT support routing The target machine must be in the same subnet as the TTM8000 If you do not specify a datatarget when configuring the measurement the receiving application will need to register itself as data target as soon as it is ready to receive data set mtu auto lt ByteCnt gt
36. I Mode Start Stop This will allow you to perform Start Stop measurements with up to 8 Stop channels at a resolution of 82 3ps You can measure both rising and or falling edges of each signal and your Stop events can occur up to 10 8ys 2 82 3ps after their corresponding Start event 5 You will perform Start Stop measurements with just one or two Stop channels What kinds of edges do you wish to detect Do you require both rising and falling edges of the same channel or is it sufficient if you detect just the rising or the falling edge of each channel If you require access to both edges proceed at step 6 otherwise go to 7 6 You will perform Start Stop measurements with just one or two Stop channel using both signal edges You should use G Mode Start Stop that will give you a 41 2ps resolution for measurement of up to 65us lt 172 6us 2 41 2ps As an alternative you can also use I Mode Start Stop that will give you a 82 3ps resolution for measurements of up to 10 8us 2 82 3ps In I Mode every measurement also contains an 8 bit Start Counter so you can detect which Start Event the event belongs to an information not available in G Mode 7 You will perform Start Stop measurements with just one or two Stop channel using just a single signal edge You should use choose R Mode Start Stop that will give you a 27 4ps resolution for measurement of up to 10us lt 230 1 5 223 27 4ps As an alternative you c
37. M8000 supports several measurement modes The most popular I Mode supports 8 external inputs with rising and falling edges at a resolution of 82 3045ps 1 12 15GHz and an infinite measurement time Other modes G R M provide finer time resolution 2 x 12 15GHz for G Mode 3 x 12 15GHz for R Mode 3n x 12 15GHz for M Mode n lt 31 but support only 2 external inputs and have a limited measurement time for each measurement Note Several measurement can follow each other without gap Thus the total measurement time is still unlimited however the event timestamps from different measurements can not easily be combined The detailed features of each mode are explained in the Key features section below 3 60 TTM8000 What s the use of a TTM8000 Assume that we have some device s up to 8 for the TTM8000 that generate electrical pulses These devices could be detectors that detect physical events in the external world e g a photon detector a Geiger counter and generate an electric pulse whenever an event occurs or they could be electronic devices to begin with that were designed to generate pulses sequences e g a clock generator or it could be an internal signal e g on a data control bus inside an electronic device The pulses generated by our devices may be highly periodic e g a clock generator or may be more or less randomly distributed Geiger counter Now we want to know if there is some correlation between the pulses from d
38. QtCore so libQtGui so and LibQtNetwork so and various links to map more specific version specific names are part of the TTM8000 software package Copy the files to a location in your PATH e g usr lib Setting up Qt on Windows On Windows you have to place the Qt Libraries QtCore4 dll QtGui4 dll and QtNetwork4 dll either directly in the folder that contains the TTMCntrl TTMViewer exectuables or in a folder that is in the PATH Setting up Qt on Mac OS X On Mac OS X you should either place the folders QtCore framework QtGui framework and Qt Network framework with all the subfolders and contained files in the System framework folder System Library Frameworks or make that the folder Qt Libraries that is in the folder with the precompiled OS X binaries stays in with the binaries If you are not satisfied to just run the provided executable and want to modify the sources to match your specific needs you will need to install the full Qt development package on your system The Qt development environment is not part of the TTM8000 software package Download it from http www qt io TTM8000 10 60 Booting the TTM8000 Connect the provided power supply 12V DC 2A to the TTM8000 Wait while the TTM8000 is booting This will take about 5 seconds Observe the following sequence of lights All LEDs yellow Booting the FPGA All LEDs red FPGA booted LEDs changing from red to yellow left to right Bootloader Erasing RAM LEDs
39. aces for a TTM8000 device and will use the first device it finds Note Most of the other commands perform specific actions on a TTM8000 device and thus need to know which TTM8000 device to work on Use connect to build this connection disconnect Disconnect from the current TTM8000 device exit quit Exit TTMCmd even if more commands are available Useful for quitting an interactive session When running commands from a file of from the command line parameters the exit is implied at the end of file set Set parameters for the next measurement Note that the settings do not become effective immediately but only when the next measurement is started If you want to change the settings of the current measurement try using the adjust command explained below set mode i64pack i64flat icont29 icont32 istartstop gmode rmode mmode lt MModeDiv gt lt Timeout gt ns us ms s Hz kHz The TTM8000 Module features several different measurement modes e l64Pack 8 Channels Rising and Falling Edges 82 3045ps Resolution infinite Measurement Range 9 months to overflow Up to 25MEvents s per TTM8000 sustained 10 MEvents s per Channel sustained 160MEvents s peak e 164Flat 8 Channels Rising and Falling Edges 82 3045ps Resolution infinite Measurement Range 3 years to overflow Up to 12MEvents s sustained 160MEvents s burst max 32 events burst e ICont29 8 Channels Rising and Falling Edges 82 3045ps Re
40. ake a quick peek at this clock and record the current timestamp along with an identification of the device that was active Thus we obtain a list of timetags where each timetag identifies a pulse from a specific device and the time at which this pulse arrived at the TTM8000 These timetag are then sent via Ethernet to a PC and can be processed there to answer all of the questions mentioned above For example if we wish to know how the events from two devices are correlated we can subtract the timestamps of their occurrences within a given time window and build a histogram of these differences If they are correlated we will find a clear spike in the histogram If we wish to measure the jitter of our pulse generator we shall subtract the timestamps of each pair of successive timestamps and draw a histogram of these differences For a good generator most differences will be in just a few bins and the remaining ones in the bins nearby A bad generator will show a wide distribution around a single center bin A very bad generator will show several center bins with a wide distribution around them For some common questions the software that comes with the TTM8000 is sufficient to obtain a complete answer e g How strongly are events of devices X Y and Z correlated What is the distribution of delays between events or How much jitter is there on the output of my pulse generator If you have a question that is very application specific you w
41. an also use I Mode Start Stop that will give you a 82 3ps resolution for measurements of up to 10 8us 2 82 3ps or TTM8000 12 60 G Mode Start Stop that will give you a 41 2ps resolution for measurement of up to 65us There is also the option to use M Mode that gives you a resolution of down to 1ps However the variance of the result is 10ps so the last few bits of a single measurement are more or less worthless when using extremely high resolution and massive averaging of many measurements is required to obtain optimal results Furthermore M Mode has another significant drawback In all other other modes a Start event can occur at any time and a new timescale starts when ever there is a Start event In M Mode you must define how long your timescale will be before you start your measurement a Start event must not occur before the timescale of the previous Start event has expired plus 1 2us for post processing and you can have at most one Stop event per channel after any Start event Thus the maximal event rate is rather limited in M Mode If you need more information about the various measurement modes their advantages and limitations you should look at the data sheet of the acam GPX TDC chip that forms the core of the TTM8000 board It can be found at http www acam de products time to digital converters tdc gpx 13 60 TTM8000 Sample Application Jitter Measurement Note This demonstration is based on the applicatio
42. and connecting to both TTM8000 either sequentially or by starting TTMViewer twice and looking at the results from both boards at the same time If we do not receive any results or just results from one TTM8000 the most probably cause is that there is a mismatch between the hardware order as defined by the sequence of cables propagating the Start signal from Start Out Start In and the software order as defined in mstart cmd where board 1 will create the Start Pulse and board 2 will wait for an external start pulse The board that creates the pulse will always start itself but it will not propagate its pulse backwards along the daisy chain TTM8000 36 60 We can even create a delay histogram for each of the active event channels measured against themselves Note that Stop2 of the first TTM8000 and Stop5 of the second TTM8000 use the same signal but are measured using two different TTM8000s whose clocks are kept in sync Thus the measured delays and standard deviations are the same for both signals If we were to remove the cable linking Ref Clock Out of the first TTM8000 and Ref Clock In of the second TTM8000 we would notice the difference in the speed of the two local crystals of the two TTM8000 Note that connecting disconnecting the Ref Clock cable while measurement is in progress will break the measurement You should stop the measurement first then connect disconnect the cable and then start the measurement again no hot plugging On
43. ate level direction of all input and output pins Get DigitallOIn can repeatedly display the state of the DigitallO pins with a given delay between measurements Example Get DigitallOIn 20 1000 set analogout 0 3 Level mV V The TTM8000 contains 4 analog output ports that can be used to control external signals Use AnalogOut to set the level of these analog output pins Valid Range 4 096V get analogin 0 3 uni bi lt RepeatCnt gt lt MilliDelay gt The TTM8000 contains 4 analog input ports that can be used to monitor external signals Each signal can either be unipolar the range 0 4 096V or bipolar in the range 2 048V Get Analogln can repeatedly read one or more of the signals with a given delay between measurements and print the results Example Get Analogln AlnO bi Aln1 2 uni 20 1000 set analoginmonitor source off 0 3 uni bi rate lt Rate gt ms s Hz get avganalogin 0 3 lt AvgMilliTime gt lt RepeatCnt gt lt MilliDelay gt If the analog signals connected to the TTM8000 s 4 analog input ports are very noisy obtaining single measurements might produce spiky results and an average measurement might convey better how the core signal moves The idea here is to set up a task on the TTM that will periodically query the TTMs and keep a history If we need a measurement we shall then look at that history and compute the average of the those samples that are no older than AvgMilliTime If
44. ate Delay Histogram Show Pair Coinc Show Multi Coinc Create Cluster Histogram Save Config Load Config Since we have only just started the TTMViewer application but have not started the actual measurement we have not received any data and thus the Measurement Mode is also still unknown to TTMViewer Sometimes it is useful to filter the incoming data before performing the real evaluation We have already selected the channels edges that we want to observe when setting up TTMCntrl Now we can perform additional filtering Some sensors detectors tend suffer from bouncing and create multiple pulses on the same Stop input for a single external event Using a Deadtime Filter TTMViewer can make sure that only the first event of each such group of events is processed and all others are discarded Whenever TTMViewer processes an event it checks if the previous event on the same Stop input is further in the past than the channel specific deadtime If it is then we have the first pulse of a new group of pulses and keep the pulse Otherwise this is a subsequent pulse that will be discarded Optionally the discarded event can retrigger the Deadtime Filter so that the deadtime counter starts over whenever a event is discarded TTM8000 16 60 If we use several Stop inputs some of the pulse sources sensors detectors will work faster have less internal delay between the external event and the pulse generated by the
45. ation section If we are using a common signal family the threshold level will be predefined and can easily be selected from the combo box otherwise we shall select Custom from the combo box and use the voltage spinbox to define our threshold voltage However for this demonstration we shall assume that Stop2 uses a threshold voltage of 1 5V while Stop5 uses a threshold voltage of 0 8V We shall therefore select Advanced in the combo box Now the button Advanced Config becomes active We can select it and obtain a dialog where we can select the threshold voltage for each input signal with a separate combo box We could also add delay measured in ticks of 82 3ps to each channel however since we don t know how much delay we want to add and can compensate for these unknown delays later on we can shall leave all these settings at 0 Advanced Settings Signal Level TTL 1 5V TTL 1 5V TTL 1 5V TTL 1 5V Custom TTL 1 5V TTL amp 1 5V v c Yv c m E E ES c E TTL 1 5V Note 0 0V seem to be a nice neutral value for a threshold voltage and it is also a valid level e g for signals symmetric around OV however it is also a very dangerous level If you leave an input unconnected it will always collect noise from the environment This noise voltage will be very small but if you compare it to OV you might
46. ber of events that become part of the histogram at all Both approaches drastically reduce the CPU load of TTMViewer Histograms Some measurement data is received at lower rates but data gets dropped at higher rates Have you enabled Jumbo Frames on your PCs Ethernet controller 57 60 TTM8000 Setting up a Network interface under Linux As mentioned in Preparing the HostPC and Booting the TTM8000 you will need a Ethernet interface on your host to connect the TTM8000 On a Linux system the Ethernet interfaces are usually called ethO eth1 eth2 and so on In the following we shall assume that your host PC contains two Ethernet interfaces where ethO is used for access to your local network and eth1 shall be used for TTM8000 First we will disconnect the current connection of eth1 so that we don t get queer side effects from previous configurations sudo ifconfig ethl down Now we can set the new IP address and netmask Since the TTM8000 board has a factory default address of 192 168 1 60 and a netmask of 255 255 255 0 for a 192 168 1 0 24 subnet we must use the same subnet for our ethernet interface Thus we must choose an unused IP address in the style of 192 168 1 x where x is an integer in the range 1 254 Note that 192 168 1 1 and 192 168 1 2 are often used by network equipment such as routers and that 192 168 1 60 is already used by the TTM8000 and thus can not be used for eth1 We recommend that eth1 is reserved for the TTM8000 module
47. ble to redefine a protected variable using the operator which will again produce a protected definition or to use the undef command to drop the current definition and then use the def command to define a new plain or protected definition Variables can also be assigned on the command line using the D or def command line option undef lt VarName gt Undefine a previously defined variable TTM8000 46 60 ttmcnvt Receive Measurement Data TTMCnvt is a tool to receive timetag data from an UDP port or read it from a file or stdin and write it to stdout in a variety of formats Note While TTMCnvt provides a variety of output formats it is of course likely that you need yet another one Since the sources of TTMCnwt are freely available please feel free to use the code there as a reference and starting point for adding the output format that suits your needs Command Line Options are f file FName Read Input from File instead of stdin n net Read Input from Network instead of stdin t ttm8 IP Port Time Tagging Module Data Source Port Default None 10502 implies n d data IP Port Local Data Port Default Auto implies n S Size CNT Automatically Quit after Processing CNT Byte e evtcnt CNT Automatically Quit after Processing CNT Events U runtume SEC Automatically Quit after Processing Events for SEC seconds F recover TICKS Enforce Recovery Time between two Events 0
48. boards sse 35 Using the User I O Pins of the TTM8000 uuu ss24sssnnsssnnnnnnnnnnnnnnnennnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn 39 Provided Command Line nennen meme nenne 41 ttmcmd Configure Control Timetagging 41 ttmcnvt Receive Measurement nennen nennen nnne naar 47 ttmmerge Merge Data from several TTM8000 48 ttmclkcalib Reference Clock Calibration cccccccccceeeeeeeeeeeeeeeececeeeeeeeeeeeeeeeeeteeeeeecseeeeeeeeeesaaeneeeees 51 Custom Applications 1 eic ES ifti ob dete pete 52 Application development on Windows 2444444440snnsnnnnnnnnnnnnenennnnnnnnnnnnnnnnnnnnnnnnnnn nenne 52 Application development on nnn rn nnns 52 Application development on Mac OS X uuussusnsssssssneennnnnnnnnnnnnnnennnnnnnnnnnnennnnnnnnnnnnnnnnrrn nenn 53 Application development for 53 Electrical and environmental
49. ce Start of Logging Cancel In the Configure Coincidence Logging dialog that pops up we can select the name of the logfile This filename can contain the macros DATE TIME and that will be replaced by appropriate data when the file is created Note Macro names are case sensitive Next we can select how often we want the coincidence data to be written to the file Finally we can select the contents of each line of logging information There is time of day and or date as definied by the PC s local clock and information for the coincidences For the coincidences we can log the current frequency number of events within the last seconds before the log entry the number of events since the last log entry and or the number of events since the start of the coincidence measurement TTM8000 32 60 Sample Application Event Clustering Bursts In this sample application we shall assume that we have a event source that has a stochastic event pattern Sometimes it does not send an event for a long time sometimes it sends a single event sometimes it sends bursts of several events within a short period of time before falling back to a long pause Note We are looking at long streams of events here where full information about the relative timing of all events is essential Thus we need a common timebase for all events and can therefore only use timetags recorded in I Mode continuous compressed or uncompressed Just loo
50. ce to thermal radiation e g direct sunlight or other thermal source nearby while in operation The analog and digital input ports on the back side of TTM 8000 are high impedance ports and sensitive to electrostatic discharge Before connecting or touching the pins make sure to touch discharge yourself by touching the mounting screws of the back panel The length of the DC supply cable must not exceed 1 m The length of the network cable should be less than 3 m to fully comply with EN 61326 1 2006 55 60 TTM8000 Trouble Shooting e All LEDs are dark Are you sure you have connected an appropriate power supply The TTM8000 Board requires 12V DC with 2Amps Note that many small power supply packs can not deliver 2 Amps Use the power supply shipped with the TTM8000 Board e During Booting the LEDs change for orange to green in a center to edge order rather than left to right The TTM8000 Board is running is Secure Mode This means that the primary server software has been detected as damaged e g after a firmware update gone awry and the backup software has been booted The board is fully functional however you should update the primary software e During Booting LED C flashes red Then LEDs A B and C change to orange and stay orange The connection between the two PCBs of the TTM8000 module is broken or the PCB is missing Please contact your service representative e LEDs A B and C are flashing orange The internal voltag
51. ce we have seen enough of this we stop the measurement using ttmcmd f path mstop cmd Of course we want to merge the measurement results from all TTM8000s into a single stream so that we can analyze them all together This can be achieved with the application TTMMerge TTMMerge will take multiple streams of data either from multiple TTM8000 boards that have been started together or from multiple timetag files that recorded the results of such a parallel measurement and will join all the timetags into one single stream of sorted timetags that can then be sent to another application for further processing or saved to file Furthermore TTMMerge can compensate timing offsets debounce bouncy time sources and even filter for coincidences Thus we shall open the file merge cmd in our favorite text editor Again we need to adjust the IP addresses of the TTM8000 boards that we will use as data sources TTMMerge does not offer a user interface that we can use to look at our data Thus we shall use TTMViewer TTMViewer however can not handle streams of multi board timetags We shall therefore use TTMMerge to shift the measurement results from the three currently interesting channels into a single board measurement before sending it to the network where it can be received by TTMViewer In Step 5 Possibility D we define where TTMMerge shall send the merged data We need to adjust the target IP address and UDP Port to the IP address of our local host
52. ckets before they can cause any harm to the Windows PC Depending on the security configuration of your PC the Windows Firewall may ask the user if an application shall be allowed to access the network Since the TTM8000 Module is connected to the PC via Ethernet all TTM8000 application need this privilege When requesting network permission Windows suggests that the application should get access to the Windows Domain network but not the Work or Home or Public network Since the TTM8000 is usually connected to its own network interface that is probably not the Windows Domain network you will need to allow access for Work or Home and Public networks too Otherwise the TTM8000 module will correctly take your measurement and send network data to your PC where the Windows Firewall will happily discard it before it can reach the TTM8000 software Network Tuning for Mac OS X On OS X Jumbo Frames can be enabled in the network properties dialog System Preferences Network Ethernet Ethernet Advanced Hardware Configure Manually MTU Custom amp 9000 The size of the network buffer under OS X is limited by the system setting kern ipc maxsockbuf You can query this value using the command sysctl kern ipc maxsockbuf Note that OS X reserves about 1 8 of the quantity specified as maxsockbuf for housekeeping overhead Thus we want 32 MByte for actual data we need to set maxsockbuf sufficiently bigger to compensate
53. common threshold for TTM signals we can easily select then TTL 1 5V entry from the menu If we had wanted a non standard threshold we could have chosen Custom and entered our own voltage manually Note that the threshold voltage selected this way applies to all channels which is fine for us since we only have one signal If we had several signals that use different threshold voltages we could chosen Advanced from the drop box and then clicked on the Advanced Config button to open a dialog that lets us enter a different threshold voltage for each channel providing finer control at the price of more mouse clicks We want to measure timing jitter between two rising edges of a signal Thus we shall enable rising edges and disable falling edges Strictly speaking it would be sufficient to enable the rising edge of the one signal that we are interested in however it does not hurt to enable the others too Note that the checkboxes for Start are disabled since I Mode cont does not use the external Start input We want to use the application TTMViewer to display the timetags that we will measure Thus the timetags shall be sent directly to a port on our local PC or any other PC in the local subnet of the TTM8000 board via UDP We can also select Receiver Req to avoid specifying the data target at this time If we select Receiver Request an application that wishes to receive the data will request that the data be sent to its port
54. create unwanted transitions between high and low level Since the noise might be of quite high frequency depending on the sources of electromagnetic noise in your lab there might even be quite a lot of transitions and the load on the TTM8000 and the PC might be quite significant Thus you are strongly advised to assign a non zero threshold to all inactive channels e g 1V would be quite fine As a additional security you should disable both rising and falling edges of all channels that do not have valid inputs attached Finally we shall select the active signal edges For our demonstration we connected signals Stop2 and Stop5 and we are only interested in rising edges Thus just two checks are required If we were careful with the threshold voltages of the unused channels then it should not matter if we leave the other channels enabled too however we prefer being safe to being sorry so we shall disable the other channels Since we are now done with the preparation of the data generation side of our measurement we can now focus on the evaluation of the data we receive Just as in the previous demonstration we shall once again use TTMViewer for this purpose Thus we start the application TTMViewer We will receive data directly from the network via UDP So we need to select the Host IP Address Option and use the same IP address and UDP port that we defined as Data Destination in TTMCntrl or use the Module IP Address Option and select the sa
55. d ttmcmd f start cmd Make LED A shine red and LED B shine green executing multiple statements from the command line ttmcmd x connect set led a red set led b green Run an interactive session with the TTM8000 Note There is no command prompt in the interactive session and most commands do not produce any visible output Just enter your commands and press Enter and they will be processed ttmcmd i connect 192 168 1 60 set led a yellow get analogin 1 3 8 250 echo Hello World exit Supported commands are list brief ext verbose all full state status lt Subnet IP Addr gt lt Port gt Print a list of TTM8000 devices discovered on all local network interfaces Print just a brief list TTMID Name IP Addr and current client an extended verbose list adding Software Firmware Versions full information about the devices and or full device information including the current connection measurement state Note It is possible to search only on a given network interface by using the n or ttmnet command line option or by explicitly stating the requested subnet in the list command 41 60 TTM8000 connect lt IP Addr gt lt Port gt Connect to a given TTM8000 device If no lt IP Addr gt or Port is provided connect will use the IP address and port provided using the t or ttm8 command line option If no such option has been provided connect will search all local interf
56. definition of measurement error is thus Remove as many bins as possible from the top of the distribution without removing more than 0 1 of the samples Do the same at the bottom The remaining bins are defined to be valid and form the core valid range To make sure that the long tail of a distribution is not unduly truncated we shall add three times the width of the core range to the top and bottom of the core valid range The resulting range seven times as wide as the core range is defined as valid range Samples outside this valid range are considered measurement errors Optionally we can have TTMViewer reset the global distribution table every time it writes a log entry This transforms the global table to a local table that is keeping track from log event to log event Note If needed the real global table can be reconstructed from these partial tables by simply adding up all partial tables 23 60 TTM8000 Sample Application Correlation Measurement In this sample application we shall assume that we have two event sources and that each source produces non periodic stochastic events Question Are the two streams of events from the two sources correlated Are there some samples occur in both signal streams while possibly other samples occur only in one stream or the other and can be considered as noise We shall apply the skills that we acquired in the previous sample application and expand the solution used there First we connect the t
57. detector than others Furthermore some pulse sources will be connected to the TTM8000 with longer cables than others Thus each channel will have a channel specific time delay between the external event that shall be monitored and the arrival of the electronic pulse at the TTM8000 If we want compare the timing of the external events we need to compensate for these delays Thus TTMViewer can optionally add a channel specific offset to the timestamp of each event Finally we will often look of coincidences of events i e look for pairs or even tripplets of events that occurred at almost the same time Single events are often of no interest Thus TTMViewer can eliminate all single event that have no neighbor on any other channel within a given time window Note that we are looking for neighbors on all channels here In real life we are generally more interested in correlations of events on specific channels not any pair of channels Thus this Single Event Filter is just a preliminary tool to eliminate many uninteresting events quickly and without causing much CPU load so that only a fraction of the data remains for further processing However in our application we just have a single signal generator as our only event source A signal generator will should create well shaped pulses so we don t need a deadtime filter Since we have just a single event source we don t need to compensate channel specific offsets to match the delays of multiple source
58. does not contain a XCode project yet However if you call without any parameters inside this folder qmake will read the TTMCntrl pro file a project file and use that to create a XCode project Once you have this XCode project file you can simply open it using Xcode modify any files that you like and build and run the application However if you wish to add remove source files to the application you should NOT do so in XCode Instead you should edit the TTMOCntrl pro file and rerun Warning qmake is picky with file path names It will not work if there are any dangerous characters such as spaces parenthesis brackets etc anywhere in the path to the project or in the file name Since qmake always fetches an absolute path to all referenced files trying to evade this restriction with relative paths made of secure characters only will not work The same approach must also be taken to compile TTMViewer and TTMUserlO Since each run of qmake creates a separate XCode project you will have three individual projects for three individual applications which is not as convenient as might be desirable but can not really be helped TTM Application development for Raspberry While the Raspberry is tiny it is still powerful and it would theoretically be possible to use the Raspberry itself to create software However this approach is not supported by the TTM8000 Software Package Instead the suggested solution is to u
59. e assume that there is lots of noise on the inputs there will be lots of spurious event groups that just happen to follow each other but that are not correlated We need to eliminate these groups We can do so by choosing a limited time range for our histogram We shall disable Full Time Range and instead define a Min Max Time Range of 100ns 100ns If we allow the system to run for a while we will hopefully obtain an histogram that is quite similar to the screenshot below Delay Histogram Start Event Stop 2 Rising Edge Stop Event Stop 5 Rising Edge vy Unordered Log Scale Time Range Full Min Max 100 1 100 ns aj BinSize 1 3 Ticks Local Delay Mean 397 27ps Std Dev 55516 91ps SampleSize 13 187 Global Delay Mean 528 20ps Std Dev 55487 35ps SampleSize 295 747 Config Log We have a wide noise floor that is more or less constant over the entire histogram and a single peak indicating the actual correlations Now we can guess the approximate location of the peak however the histogram will probably be too wide to obtain an accurate reading We shall therefore redefine the Min Max Time Range to enclose our peak tighter e g 10ns to Ons looking at the scale at the bottom of the histogram and obtain a new histogram 27 60 TTM8000 Delay Histogram y Log Scale Unordered vv u J a 22 2 2 in 8 5 u gt i a 4 gt
60. e to send it Make sure that in the TTMCntrl s Data Destination you have selected UDP and Target Request Also make sure that you in TTMViewer s Data Source section you selected Module IP Addr and the correct TTM8000 Module if you have more than one TTM8000 If measurement data is created and sent but it is not received than it is probably lost on the network We know that the overall network communication works fine since we were able to discover the TTM8000 connect to it and configure a measurement Thus the fault can not be missing misconnected broken network cables misconfigured network interfaces or other hardware trouble Just the measurement data gets lost This is almost certainly due to a security restriction implemented on the local PC If you are working on a Windows PC there is the Windows Firewall that is automatically installed with the operating system When it detects an application wanting to receive data from the net it may depending on your local configuration ask if you which to permit this communication By default it recommends to allow this communication only within your domain network However if you have installed a separate network interface just for TTM8000 this network interface will not be a domain network interface and you will need to either make this network interface a domain network interface or permit network traffic for other types of network interfaces too The Windows Firewall is very persist
61. ead this liberally documented file since it will explain many of the options of ttmcmd For the moment however most options have already been set to reasonable values The only settings that really must be adjusted are the IP addresses of the boards They are listed in the section Step 1 Connect to the TTM8000 Boards and must be adjusted to match the local setup Note that the order in which the boards are listed is essential When we connected the Start Out from the first board to the Start In of the other boards we defined an hardware ordering of the boards and we must properly reflect this hardware ordering in our software configuration If you are using a signal generator with two complementary outputs rather than an active signal splitter with two equivalent outputs you should also edit section Step 2c Enable Disable Signal Edges to disable the rising and enable the falling edge of channel 2 5 or at your choice 1 2 but not both so that both channels actually measure the same logical event While we are at it we shall also open the command script mstop cmd and perform the same adjustments to the IP addresses there Remember to save your changes Now use TTMCmd to process the scipt file ttmcmd f path mstart cmd Hopefully both TTM8000s will come to live The Run and Buffer LEDs of both TTM8000s will become green as well as User LED A and data will be available for inspection We shall validate this by starting TTMViewer
62. ent and once a rule forbidding traffic is installed it will execute it Even turning the entire Firewall off does not take effect at once Try the advanced setting page of the firewall settings to see which rules are actually in effect If you are not a Windows geek and or don t have administrator privileges on your local PC you should seek assistance from your local system administrator to create suitable firewall rules for TTM8000 Note to the system administrator TTM8000 uses UDP IP not TCP with on ports 10501 and 10502 on the TTM8000 side and arbitrary ports on the PC side Using the hints above we have now hopefully brought TTMViewer to life We received our data via UDP Since only a single process can consume a given UDP packet we consumed this information However it might be useful to write the timetags to file while watching them and or pass them on to a different process for further processing daisy chain Both options are available in TTMViewer using either the original data as received from the net or the modified filtered data after it has passed through the Deadtime Filter Offset Adjustment and or Single Event Filter TTM8000 18 60 Now we know that TTMViewer is receiving some data however we do not yet know anything about the timetags received We shall therefore click on Show Event Counters to open a window showing how many events are recorded on which channel Event Counter T1M8000 Signal Event Counter Frequency
63. ents is given by the formula Freq ChnA Freq ChnB WindowWidth 2 If we have events the formula is given by Freq ChnA Freq ChnB Freq ChnC WindowWidth 3 and for 4 events by Freq ChnA Freq ChnB Freq ChnC Freq ChnD WindowWidth 4 In our example the pairwise false positive rate between Stop2 and Stop5 computes to 201000Hz 302000Hz 1ns 2 121Hz Thus our 1134 detected coincidences consist of about 121 false positives and 1013 actually correlated events Of course this is a statistical property that will fluctuate with time Note The signal sources for this demonstration actually consisted of three signal generators Two generators running at 200kHz and 301kHz respectively created the background noise and one generator running at 1kHz created the correlated signal that was mixed in with both noise signals As with histograms we can write the results from the coincidence window to a file for later processing First we shall select the way we log our data by clicking the Config Log button Configure Coincidence Logging Log File home ieger Multi Coincidence DATE CNT log Hint Use DATE TIME and CNT as wildcards Write a Log Entry every 5 seconds Autostart stop Logging when Event Processing is started stopped Log Time of Day Log Date y Log Multiple Coincidence Frequency Log Number of Multiple Coincidences since last Log Entry y Log Number of Multiple Coincidences sin
64. er cables of different length Note that offset correction is done in steps of TTM8000 ticks 82 3ps so in general you will not be able to shift the inputs to a perfect zero offset 37 60 TTM8000 can however do more than just merge multiple streams of timetag data and shift the timing of signals It can also perform filtering for coincidences In our setup we have two signal streams that are derived from a common source and that have a constant offset which we just adjusted to make it zero but the third stream of events has an independent timing so sometimes there will be events quite close to the other stream s and sometime they will be far away We are only interested in groups of events where something happened on all three channels at the same time We shall once again open ttmmerge cmd in our favorite text editor Just for cleanup we do no longer wish to look at the live data in TTMViewer we can comment out the dataview send command in from Step 5 Possibility D Instead we shall look at Step 5 Possibility E and remove the comment from the statement there We want a report of all coincidences with 3 up to 8 events within a coincidence window of 30ns and write those to a text file All events that are not part of such a triple coincidence will be discarded Of course writing all these events to file will quickly create a huge file To make sure that we do not forget TTMMerge and our hard disk overflows
65. es des tina tina tina tion tion tion TTM8000 TTM8000 Contact Roithner Lasertechnik GmbH Wiedner Hauptstra e 76 1040 Vienna Austria www roithner laser com Phone 43 1 586 52 43 0 Fax 43 1 586 52 43 44 60 60
66. es of the TTM8000 board are out of spec and or the TTM8000 is overheated Disconnect the TTM8000 from power immediately and contact your service representative e The Demo Applications for Windows won t start because MSVCR80 dll MSVCP80 dll or MSVCR100 dll is missing The demo applications are linked against the Microsoft Visual Studio C Runtime environment This runtime environment is used by many applications and is therefore already installed on most machines If it is missing on your machine and Windows issues the message The program can t start because MSVCR80 dll or MSVCP80 dll or MSVCR100 dll is missing from your computer Try reinstalling the program to fix this problem you need to install the runtime environment packages They are available in the Visual Studio Library folder on your installation CD or can be downloaded from Microsoft at Microsoft Visual C 2010 Redistributable Package x64 for MSVCR100 dll http www microsoft com en us download details aspx id 14632 Microsoft Visual C 2005 SP1 Redistributable Package x86 for MSVCR80 dll MSVCP80 dll http www microsoft com en us download details aspx id 5638 e TTM8000 Module can t be found on the network Make sure your PC s network interface is configured correctly Initially the TTM8000 board must be operated in the 192 168 1 0 24 network If you have misconfigured the TTM8000 network settings you can revert to factory defaults Press the Button before p
67. events from these two channels will be merged This merging causes information to be lost because the event in the output stream does no longer carry information that would allow use to identify which of the two input stream it originally came from dataout send singlepacked net 192 168 1 56 10505 channelmap gt X 1 2 gt 1 2 2 2 gt 1 2 2 5 gt 1 4 2 7 gt 1 6 Look for coincidences of at least 3 event and at most 8 events that all occurred within 30ns and write the events that participated in this coincidence to file Note that we do not specify which events shall participate in the coincidence We are just looking for coincidences of any events This will hopefully eliminate most of the noise More delicate filtering for specific coincidence patterns and other processing can than be done with custom programs that can use their delicate algorithms on the reduced dataset dataout write text file CoincMergedTTMData txt mincoinccount 3 maxcoinccount 8 coincwindow 30ns TTM8000 50 60 ttmclkcalib Reference Clock calibration The TTM8000 is equipped with a oven controlled crystal oscillator OCXO that is used as time reference for the timing measurements While this crystal is already very accurate in itself it can be tuned for even better precision within a range of 40ppm This feature can be used to align the frequency of the OCXO to a high quality time reference e g a rubidium clock or to match the reference c
68. f a board by using a e g 2 Time is specified as decimal numbers with a suitable unit ms us ns ps Internally these offsets are converted to ticks of 82 3045ps so the resolution of offset compensation is limited to one tick Note that it is also possible to use or instead of the simple in the assignment to increase decrease the offset This can come handy when e g the cable length is changed and the additional delay introduced here is to be computed rather than measured Example offset 2 5 3ns offset 4 2 7ns Detectors that convert external event to electrical pulses are sometimes not perfect Some tend to create afterpulses or bounces i e a single external event causes an entire stream of electrical pulses rather than just a single electrical pulse TTMMerge can eliminate these unwanted additional pulses It will declare pulses that come within a specified deadtime interval after the previous event on the same channel as afterpulses and delete them There is an optional re triggering of the deadtime Without re triggering TTMMerge will delete pulses that arrive within the deadtime interval measured from the first pulse of the pulse group With re triggering it will restart the deadtime every time a pulse is detected thus the deadtime interval will be measured from the most recent not the first pulse of a pulse group deadtime lt BoardID gt lt StopID gt gt Time The lt BoardID gt lt StopI
69. format ttmcnvt n ot Read timetags from the net and write them to stdout in a verbose user defined format ttmcnvt n oT Channel CHN Slope SLOPE Time TIME Read timetags from the net and write just the times no channel number or slope as human readable text ttmcnvt n oT 6 Read timetags from the net and create a frequency table of the results Press Cntrl C once you have gathered sufficient data to force TTMCnvt to print its findings to stdout ttmcnvt n os Read timetags from a particular UDP port on the local host and write them to a file ttmcnvt d 192 168 1 66 10502 ob gt MyTimetags dat 47 60 TTM8000 ttmmerge Merge TTM Data from several 8000 boards If you have a large measurement setup and the 8 stop channels of a single TTM8000 board are not sufficient for your measurement you can combine up to 16 TTM8000 boards to create measurements with up to 128 stop channels Since the clocks of all TTM8000 boards can be synchronized to each other they will not drift apart and all timestamps from all boards can be compared against each other TTMMerge will take all the measurements from multiple TTM8000s compensate the offsets that arise from using event sources with different speeds and or differences in cable length and combine the resultis into a single stream of sorted timetags Furthermore TTMMerge can act as filter and eliminate duplicate events within a specified deadtime and searc
70. g edge of one of the outputs and on the falling edge of the other to simulate two synchronous signals Another simple cable can be used to connect the output of the other pulse generator to a single input Using the first of our SMB cables we connect the Ref Clock Out connector at the back of the first TTM8000 to the Ref Clock In connector on the backside of the second TTM8000 Hopefully the Clock Status LED next to the Ref Clock connectors will now change from red to green on the second TTM8000 indicating that the second TTM8000 now receives its reference clock from an external source The Clock Status LED will remain red on the first TTM8000 since it is still running on its internal crystal clock If the Clock Status LEDs do not show the expected colors the clock inputs outputs are probably not configured correctly You can fix that by issuing the following command for each TTMBoard ttmcmd t 192 168 1 xxx x connect config clocksynth useexternclkout true externclkoutfreq 10MHz useexternclkin true externclkinfreq 10MHz externclkinlevel 1 4V Note that this is one command to be written in a single line Obviously you need to set the correct IP Address for each board in the t parameter You can obtain a list of all TTM8000 boards with their IP Addresses using the command ttmcmd list 35 60 TTM8000 If we had more than two 8000 boards we could using additional cables connect the Ref Clock Out connector of the second TTM80
71. groups are noise We wish to get rid of the noise as soon as possible to reduce the amount of data that has to be processed later on This too can be handled in TTMMerge Note DataOut commands can become quite long It is possible to split a single DataOut command into several lines by ending a line with a character directly followed by the line break no spaces or other text inbetween to indicate that the command will be continued on the next line dataout send Format net lt IPAddr gt lt UDPPort gt lt ChannelMapping gt lt CoincFilter gt dataout write Format file lt FName gt lt ChannelMapping gt lt CoincFilter gt Where Format is one of flat flat multiboard format 8 Byte event up to 16 boards packed packed multiboard format 4 Byte event up to 16 boards singleflat flat singleboard format 8 Byte event 1 board singlepack packed singleboard format 4 Byte event 1 board text ASCII text for files only lt IPAddr gt lt UDPPort gt specifies the target IP Address UDP Port that TTMMerge will send its data to lt FName gt is the name of the output file lt ChannelMapping gt is optional and indicates how input channels will be mapped to output channels Note that it is acceptable to map multiple input channels to a single output channel which will result in an output channel that contains all events from the contributing input channels but a single input channel can only be mapped to a single output
72. h for coincidences multiple events occurring at the same time within a specified coincidence window These filtered and sorted timetags can then be sent via network to some other application for further processing can directly be saved to file in binary format for later processing by some application or be printed as ASCII text for human reading Since ttmmerge needs a lot of configuration to work as intended it requires a configuration file whose name must be passed as a command line parameter The only useful Command Line option is f script FName Select the Configuration File When writing a configuration file it is strongly recommended that you take a look at the liberally documented sample script that is provided in the TTM8000 software release programs Scripts merge cmd and use it as a starting point for your experiments In the beginning we need to define how TTMMerge shall obtain the raw timetags that it will work with TTMMerge can either connect directly to physical TTM8000s or it can listen at specified UDP IP Ports or it can read the timetags from files While a connection to a TTM8000 port can carry only the data from this single 8000 the other two options also permit the use of preprocessed data i e the output of another TTMMerge application that already contains the data from multiple TTM8000s Note that TTMMerge will read its data either only from network or only from file Mixing files and network con
73. h to find the optimal setting for the coarse tuning voltage while leaving the fine tuning voltage in a middle setting and will then keep the coarse tuning voltage fixed and perform binary search to find the optimal setting for the fine tuning voltage All this searching for the optimal settings is fully automatic All you need to do is connect the reference signal to any of the Stop inputs and not connect anything to the other Stop inputs and start TTMCIkCalib Then wait about 30 seconds while TTMCIkCalib is working and thats it The calibration results will automatically be stored in the TTM8000 and will remain effective even after power cycling the device Example usage assuming a 100kHz reference clock ttmclkcalib f 100000 If you know that the clock is already quite well calibrated you can skip the coarse calibration and just try to perform fine tuning by adding the option a and save half the calibration time Other available options are t ttm8 IPSPOrt Target Time Tagging Module Default Auto 10501 n ttmnet IP Port Time Tagging Module Subnet Default Auto 10501 c cntrl IP Port Local Cntrl Port Default Auto Auto f freq Input Frequency Hz a fin Fine Adjustment Only S seekonly Only look for optimal adjustment Dont Flash W wait Wait for Any Key before quitting V verbos Show Internal Information V version Show Version Information h help Show this Text 5
74. he diagram best for showing variations of the event rate of a single channel over time or to scale all curves so that the highest curve uses the full height of the diagram and all other curves use the same scale best for comparing the relative rate of various event Sources The Event Counter window shows the current event frequency as text and some history in the graph however if we want to perform long time measurements the start of the event counter history will long have scrolled out of view before we finish our measurement Thus it will be useful to record the signal rates to a logfile that we can check later to see how our signal sources behaved over time To set up logging click on Config Log Here we can define the name path of the log file Note that TTMViewer will never overwrite an existing file If it finds the filename already used it will append a counter to the filename MyStatistics dat becomes MyStatistics 2 dat or if that is already used too MyStatistics 3 dat up to MyStatistics 100 dat In addition to this TTMViewer supports macros in filenames and will substitute TIME DATE and COUNT or CNT with appropriate contents Note that macro names are case sensitive Furthermore we can choose how often TTMViewer will write data and if logging is automatically started stopped when data collection is started stopped or if we wish to manually activate logging only when needed Finally we can define which data fields shal
75. his TTM8000 board will be treated as board with index lt BoardID gt within the range 1 16 If the data file already contains data from multiple TTM8000s combined by a different copy of TTMMerge you should set lt BoardID gt to Example datain 3 read file TtagFile89 dat datain read file CombinedTtags dat We have now aquired timetags for events that originated from different sources were converted to electrical pulses by different detectors with different internal speed and traveled to the TTM8000s over cables of different length Furthermore the different TTM8000 also were not started at the exactly the same instant but using a daisy chained start signal where each link introduces a fixed but unknown delay Thus two external events that actually occurred at the same time now have timetags with an offset For a given measurement setup this offset is fixed and can be compensated with a simple addition Note that determining the correct TTM8000 48 60 value of this offset is part of the planning of the experiment and might be quite tricky In many cases using a correlation will help see the walk through in chapter Sample Application Using Multiple TTM8000 boards Once we know the correct offsets we can tell TTMMerge offset lt BoardID gt lt StopID gt gt Time The lt BoardID gt lt StopID gt usually referes to a single Stop input of a single TTM8000 board e g 2 6 but you can also refer to all Stops o
76. ialog Multichannel Coincidences Stop 1 Stop2 Stop3 Stop4 Stop5 Stop amp Stop7 Stop8 Freq Hz Counter Y 201 000 7 982 603 Y 302 451 12 011 681 Y Y 1134 42 633 Y Y Coincidence Window Width Config Log Start Log Reset Counters 31 60 TTM8000 In the Multichannel Coincidence Dialog we can select up to 12 coincidences of multiple events For each of these multiple coincidence counters you can define which channels must be triggered in sync to count a coincidence event You can select a single event and receive the same results as the regular single counter or two events and receive the same results as the core pair event counters or more events and obtain additional results In our example we only have two signals thus we shall configure their coincidence and as additional example we shall also configure the two single events and an additional 3 fold coincidence that shall of course never trigger since the third event will never arrive in our setup Note The limit 12 is again not a technical limitation It was just chosen to keep the dialog size down if you need more just add more dialog elements See MultiCoincidences cpp MultiCoincidences UpdateCounters Note Even signals that are from totally independent random sources will have some coincidences since some random events will simply happen to occur at the same time even so they are not correlated The approximate number of such events for two ev
77. ifferent devices and or if there is some auto correlation in the pulse stream of a single device If we receive a pulse from device X does this change the likelihood that we will also receive a pulse from device Y within a given time window Do events from devices X and Y usually sometimes always occur together or are they mutually exclusive What about events from devices X Y and Z together If received an event from device X how long will it take before the next event arrives from this device What is the complete distribution function of the delay between two events Are the events actually randomly distributed and we observe a perfect exponential distribution or is there some hidden connection between events that changes the distribution Possibly we can assume that the events are indeed perfectly randomly distributed but our detector has some losses maybe insensitivity during a deadtime after an event was detected or dark count of events that are not actually there Are the pulses generated by our frequency generator actually equidistant or does the generator generate lots of pulses that are slightly to short and then compensates with a single long pulse to obtain the correct average pulse length How much jitter is there All the above questions can be answered using a high resolution clock in the case of the TTM8000 the clock ticks at 12 15GHz in I Mode and a multiple of 12 15 GHz in the other modes Every time an event is detected we t
78. ile home ieger TimeTags dat Received OKByte OKByte s Load We are using two signal sources one for each channel Hopefully we already know what signal levels our sources provide Otherwise we should now fetch the documentation of the signal sources and read them to find out what they provide If that fails we should fetch an oscilloscope and measure the high low levels Usually we will have the 50Ohm termination resistor installed on the inputs of our TTM8000 to reduce signal overshoot To obtain comparable signal levels on the oscilloscope we need to make sure that the oscilloscope also uses a 50Ohm termination on its probes If our signal sources can not drive 50Ohm we need to remove the jumpers next to the corresponding TTM8000 s Stop inputs and perform our signal level measurements after switching our oscilloscope inputs to high impendance mode TTM8000 24 60 Now that we know inputs levels with the same termination as used by the TTM8000 we can configure the correct threshold levels For simplicities sake we shall use threshold values that are half way between the measured minimal and maximal signal level We might be able to be more accurate if we choose the point where the signal gradient is steepest and thus jitter is lowest but just using the middle between minimum and maximum is generally more than good enough If all signals use the same threshold we can simply set it in the Signal Input Level Signal Delay Compens
79. ill probably not be able to obtain the answer using only the software that comes with the TTM8000 If these cases you will need to write your own software to process the timetags However since the documented source code of the TTM8000 software is included in the TTM8000 distribution you have working code that gives you an environment that handles all the setup data handling etc allowing you can focus on your application specific processing TTM8000 4 60 Key features e 4 Measurement Modes I Mode 8 channels 82 3ps Resolution up to years Measurement Range Up to 25MEvents s per TTM8000 10MEvents s per channel sustained 180MEvents s burst max 32 events burst Trigger on rising and falling edges G Mode 2 channels 41 2ps Resolution 65us Measurement Range Up to 20MEvents s per TTM8000 sustained 180MEvents s burst max 32 events burst Trigger on rising and falling edges R Mode 2 channels 27 4ps Resolution 40us Measurement Range Up to 20MEvents s per TTM8000 sustained 180MEvents s burst max 32 events burst Trigger on rising or falling edges M Mode 2 channels 1 0 27 4ps Resolution 10ps variance Up to 500k measurement intervals per second Trigger on rising or falling edges Use internal reference crystal standard crystal oscillator or optional oven controlled crystal oscillator OCXO or external reference clock 10 20 40 80MHz Generate output reference clock 1 2 5 10 20 40 80MHz for
80. ithin your company network this dedicated network will probably not be a Windows Domain network but a Work or Home or Public Place network So be sure that you enable network communication for Work or Home and Public Place too otherwise the Windows Firewall will continue to block TTM8000 56 60 your traffic On Windows XP the Firewall settings can be reached by opeining the Control Panel use the Start Menu and select Control Panel and selecting Security Center and Manage security settings for Windows Firewall On Windows 7 you can disable the Windows Firewall by opeining the Control Panel use the Start Menu and select Control Panel and selecting System and Security and Windows Firewall If you want to exercise precise control over the hole punched into the Windows 7 Firewall you can use the Advanced Settings option in this dialog All that is really needed is an Inbound Rule that allow TTMViewer to communicate with any remote device via UDP at remote ports 10501 and 10502 and any local port TCP is not used by the TTM8000 Software If you misconfigured your firewall rules this is also the correct place to fix things e g delete the settings for TTMViewer while TTMViewer is not running and have a new go at the optimal configuration the next time TTMViewer is started The Windows Firewall is disabled but the TTM8000 Modules are still not found If the TTM8000 Modules are still not found after the
81. king at the average event counts will not reveal this irregularity Using a histogram of the event against itself helps a little but is unable to distinguish between two burst of two events each and a single event followed by a burst of three events We shall use the Create Cluster Histogram button in TTMViewer to create a Cluster Histogram Window Cluster Histogram TTM amp 000 Window Length 10 Log Scale Trigger Source Event Retrigger Ignore Trigger Pulse Stop1 Stop2 Stop3 Stop4 Stop5 Stop6 Stop7 Trigger Events Y Counted Events Y Local Clusters Mean 4 19 Std Dev 0 65 SampleSize 82 825 Global Clusters Mean 4 19 Std Dev 0 65 SampleSize 1 484 272 Config Log Start Log Obviously when we want to analyze clusters of events we need to have some definition of when a cluster starts and when a cluster ends Here we have two option We can either split the global time into time windows of fixed length and consider all the events within one such window to belong to one cluster Alternately we can define one or several trigger events and define a cluster as starting at that trigger and lasting for a fixed window time In the later case we must decide how we want to handle re triggers i e what shall happen if a new trigger event comes along while the previous cluster is still in progress We can either ignore the new trigger event thus all clusters have the same length ho
82. l be included in the output file If Autostart Stop is enabled a new Logfile will be started every time you Start a new measurement in TTMViewer Otherwise you need to Start Stop the measurement manually using the Start Log Stop Log Button of Event Counter TTM8000 20 60 Configure Event Counter Logging Log File home Aieger Event Cnt 96 DATE log Browse Hint Use DATE TIME and CNT as wildcards Write a Log Entry every second Autostart stop Logging when Event Processing is started stopped Log Event Frequency per Channel y Log Event Frequency Sum Log Event Count per Channel Log Event Count Sum Log Current Date Log Current Time The resulting file is a simple tab separated value file that can easily be opened with the spreadsheet application of your choice e g OpenOffice Calc KSpread Excel Numbers etc Now that we are sure that we receive timetag data lets have a look at the timing distribution Click on Create Delay Histogram to open a histogram window Delay Histogram Start Event Stop 1 Rising Edge Stop Event Stop 1 Rising Edge Unordered y Log Scale Time Range Full Min Max 0 10 BinSize 1 5 Ticks Local Delay Mean 5000000 00ps Std Dev 81 03ps SampleSize 199 963 Y Global Delay Mean 5000000 00ps Std Dev 80 67ps SampleSize 2 343 910 Config Log Write Log We only have a single signal at Stop1 so we can only look at this signa
83. l with reference to itself We shall therefore select a Stop1 Rising Edge as both Start Event and Stop Event TTMViewer will immediately 21 60 TTM8000 display a histogram of the delays In addition to that we have the mean the standard deviation and the number of samples received within the last second and since the start of the measurement or the last reset In general we observe a long flow of timetags When we look at the difference between two different signals we must make a decision how we want to find pairs of events whose timing difference we can observe Do we have an obvious start event that is strictly followed never preceded by possibly multiple or none stop events that belong to this start event or do we want to group a stop event to the nearest preceding or following whatever is closer start event without enforcing a strict order In the later case we should check the Unordered checkbox Since we are using only a single signal for our demonstration only ordered observations make sense and the setting of the Unordered checkbox is irrelevant The histogram can be drawn using either a linear or logarithmic scale While a linear scale is more familiar to most users and gives more feeling about the distribution using a logarithmic scale allows us to distinguish differences even in the less frequented parts of the histogram that would otherwise be lost in the finite resolution of the screen The histogram of the current
84. lock frequencies of two TTM8000 boards Note that even after calibration the clocks of two TTM8000s will still have some drift against each other Thus clock calibration is no substitute for a hardware clock synchronization using a cable from the reference clock output of one TTM8000 or some other clock reference to the clock input of the other TTM8000 Furthermore every clock crystal changes its frequency as it ages Thus you might want to perform recalibration from time to time depending on your needs with regard to absolute time precision Note that all crystal oscillators are sensitive to changes in temperature Thus you should make sure that the TTM8000 and your reference clock have been turned on for some time 715 minutes so that their internal temperature had time to settle before performing the calibration TTMCIkCalib will take a reference signal of known frequency 10kHz 10MHz that is connected to one of the Stop inputs of the time tagging logic and then measure how long it takes to receive as many events as should occur within a second If it took more than one second when measured on the TTM8000 internal clock then the TTM8000 clock is too fast and needs to be slowed down If it took less than one second the TTM8000 internal clock is too slow and needs to be speed up The TTM8000 hardware actually uses two voltages to tune the OCXO one for coarse tuning and the other for fine tuning TTMClkCalib will first use a binary searc
85. mat 8 Byte event up to 16 boards packed multiboard format 4 Byte event up to 16 boards flat singleboard format 8 Byte event 1 board or packed singleboard format 4 Byte event 1 board Flat formats are easier to process since they don t require unpacking by the receiving application however they incur twice the network load of packed formats Multiboard formats can handle 16 TTM8000 Boards 128 stop inputs but are not compatible with some applications such as TTMCnvt or TTMViewer When writing an output stream to file we can also use the four binary formats stated above but can also use ASCII text format Text format is not supported for network transmission When reading the input data we assigned a lt BoardID gt to each input stream and the lt StopID gt was already part of the each event Sometimes the resulting set of lt BoardID gt lt StopID gt is inconveniant and it might be nice to rearrange the numbering This is in particular true when writing data in singleboard format where we need to select the max 8 channels that will be written while all the others will be dropped Note that by mapping several source channels onto a single destination channel we can also merge the events from two input channels 49 60 TTM8000 Sometimes we are only interested in groups of events that occur at almost the same time while the remaining single events are to be considered noise or vice verso the singles are interesting while
86. me TTM8000 Module as chosen in TTMCntrl 25 60 TTM8000 Our preparations are complete We can press Start in TTMViewer to begin receiving timetags We can press Start in to Start sending timetags TTMViewer comes to life We can see that TTMViewer automatically detected the type of measurement we selected in TTMCntrl and starts receiving data In the Event Count window we see that the data is receive in the two selected Stop channels The total number of timetags received as well as the number of timetags received within the last second is displayed for each channel as text and graphically Event Counter TTM8000 Signal Event Counter Frequency Rising Edge Falling Edge Count Freq Hz Count Freq Hz Stop 1 0 0 0 Stop 2 57 722 933 201 000 Stop 3 0 Stop 4 0 Stop 5 86 862 264 Stop 6 0 Stop 7 0 Stop 8 0 lt lt lt lt lt lt lt Event Frequency History wv Use Common Scale for all Lines Reset Graph Config Log Start Log Reset Counters We know assume hope that there is a correlation between the signal sources and that some measurements we receive on Stop2 correspond to other measurements that we receive on Stop5 however we shall assume that there is lots of noise measurements on Stop2 that do not correspond to any measurement on Stop5 and the other way round Furthermore we assume that each signal source and the cable between the
87. measurement parameters as Non Compressed l Mode however we exploit the fact that the high bits beyond bit 27 of the timetags change only rarely once every 11ms 22 82 3ps and need not be transferred for every timetag Thus only one 32 bit word is transmitted for every timetag and rarely another 32 bit word is transmitted as the high bits change resulting in an saving of almost 5096 at high data rates Thus twice as many events can be recorded in Compressed I Mode as in Non Compressed l Mode Of course the receiving application will need to decompress the data it receives However this decompression is easy to implement with a single TTMLib library call to TTMData c ExpandData and fast to execute Indeed receiving and decompressing compressed data puts less load on the local CPU than receiving uncompressed data which requires twice as many network packets for the same number of events Thus Compressed l Mode is definitely recommended over Non Compressed I Mode 3 You will measure data by using one Start channel whose events define the beginning of a new timescale and one or more Stop channels whose event will be measured on these timescales You will not be able to determine the relative offsets between two timescales How many Stop channels do you require If you require more than two Stop channels you must continue at step 4 If two Stop channels are sufficient for your task proceed at step 5 4 You should use
88. n two TTM8000 boards we could again use a daisy chain solution by connection the Start Out at be back of one TTM8000 to the Start Input on the front of the next board or we could use an active signal splitter to distribute the Start Out signal of the first TTM8000 to the Start Input of all other TTM8000s Finally we shall hook up the sample signals from the signal generators of the TTM8000s to some Stop inputs We shall choose to connect the input of the active signal splitter to the Cal ibration Out output of the first TTM8000 and connect the split signal to Stop2 of the first TTM8000 and Stop 5 of the seconds TTM8000 Furthermore we shall connect Cal Out of the seconds TTM8000 to Stop7 of the second TTM8000 This choice was totally arbitrarily we could have used any other combination just as well including connecting all signals to Stop inputs of the same TTM8000 which would negate the effect of demonstrating a Multi TTM8000 setup or using Stop inputs with the same index on both TTM8000s however the choice that we make here will be reflected in the way we evaluate our results so until further notice we shall assume the above selection Included with the TTM8000 software package there is the script file mstart cmd located at programs Scripts mstart cmd that will use the command line application TTMCmd to start all our TTM8000 boards in perfect sync You should now open this file with your favorite text editor You are strongly invited to r
89. nce clock to synchronize with other TTM8000s and or other devices The generated reference clock is in perfect sync with either the TTM8000 internal oscillator or the external reference clock Its speed is selectable to be 10 20 50 100 200 or 500 kHz or 1 2 5 10 20 40 or 80MHz using TTMLib Library function TTMOntrl c SetExternClockConfig or UpdateExternClockConfig or the TTMCmd commands set config clocksynth e Clock Status LED The Clock Status LED shows the state of the TTM8000 reference clock Off External clock valid but Internal Clock used Red External clock input missing or invalid frequency Internal Clock used Green External clock valid and in use 7 60 TTM8000 Digital I O Port The TTM8000 features 8 digital general purpose I O ports 3 3V that have no TTM8000 specific purpose and can be used by your application for whatever purpose seems appropriate The direction value of these pins can be set using the TTMLib function TTMCntrl c SetUserlO GetUserlO TTMUserlO application or the TTMCmd commands set digitaliodir set digitalioout and get digitalioin WARNING These pins are directly connected to the TTM8000s internal FPGA without any protective circuitry Do not overload short circuit these pins The analog and digital input ports on the back side of TTM 8000 are high impedance ports and sensitive to electrostatic discharge Before connecting or touching the pins make sure to touch discharge you
90. nections is not permitted datain lt BoardID gt connect lt BoardIPAddr gt Connect to the TTM8000 board specified by lt BoardIPAddr gt Treat this TTM8000 board as board with index lt BoardID gt BoardID must be in the range 1 16 Example datain 3 connect 192 168 1 89 datain lt BoardID gt read net lt LocallPAddr gt lt LocalPort gt Read Timetag Data from UDP IP port lt LocallPAddr gt lt LocalPort gt lt LocallPAddr gt must be the an IP Address of your local computer and LocalPort must be UDP port that someone else sends timetags to This could e g be a TTM8000 board or another copy of ttmmerge or some other application Note that only one application can listen to a given UDP IP port at any time If you have lots of connections you will need to think of a numbering system that will assign a unique UDP port to each connection If the data stream contains only data from a single TTM8000 this TTM8000 board will be treated as board with index lt BoardID gt within the range 1 16 If the data stream already contains data from multiple TTM8000s combined by a different copy of TTMMerge you should set lt BoardID gt to Example datain 3 read net 192 168 1 56 10506 datain lt BoardID gt read file lt FName gt Read Timetag Data from a binary file of Timetags such as written by TTMCntrl TTMViewer or TTMMerge Reading Text ASCII files is not supported If the data file contains only data from a single TTM8000 t
91. nput or output WARNING The digital I O pins are directly connected to the internal FPGA without any protective circuitry They are designed to provide logic signal and are not suitable for driving external loads without external power drivers Be very careful not to overload these pins as this might result in permanent damage to the TTM8000 hardware The 4 analog inputs can operate either in unipolar mode where they can measure voltages from 0 to 4 095V or they can operate in bipolar mode where the measurement range is 2 047 to 2 047V Analog to Digital Conversion is done using a 12 bit ADC providing a measurement resolution of 1mV The 4 analog outputs can generate voltages in the range of 4 095V to 4 095V Digital to Analog Conversion is done using an 8 bit DAC providing a resolution of 32mV WARNING The analog outputs must only be used as control reference voltages They are not power supplies Do not load them with loads less than 4000 The application TTMUserlO provides simple access to these functions TTM8000 User 1 0 Control TTM8000 120 Time Tagging Module Module IP Addr 192 168 1 83 TTM8000 120 Re Scan Net Disconnect Digital Input Output LockDir 0100 0101 0102 DIO3 0104 DIOS DIOG 0107 Dir Out Dirin Pin Out Pinin Analog Input 0 AIn1 Aln2 Aln3 0 000 V 0 000 V 0 501 V 0 927 V Bipolar Bipolar Bipolar Bipolar Analog Output Auto Aout 0 2 wy fmf cone mf mf oce Dm
92. ns TTMCntrl and TTMViewer which make use Qt4 Qt4 is a cross platform application and user interface framework available under LGPL GNU Lesser General Public Licence from http www qt io It is part of many popular Linux distributions and is either installed by default or can easily be added using the package manager of your Linux system Windows and OS X users will need to download and install it manually Please make sure Qt is installed on your system before proceeding If you do not want to install the full Qt development system but just want to use TTMCntrl and TTMViewer you will find the libraries needed to run these applications on the TTM8000 Installation CD For Linux and Windows you should copy the Qt library DLL files to the same folder as the TTMCntrl and TTMViewer applications For OS X you should place the Qt frameworks in the System Framework folder Note that you will not be able to compile modified copies of TTMCntrl and TTMViewer without installing the full Qt development system Use your signal generator to obtain a square wave of about 200kHz with a low signal level of about OV and a high signal level of 3V Connect the output of your signal generator to the TTM8000 input Stop1 Start the provided GUI application TTMCntrl TTMCntrl will automatically search for available TTM8000 devices on all network interfaces of your computer and will list all discovered devices in the drop down menu Note If TTMCntrl does not list your TTM
93. nt of Global FreqTable excluding Measurement Errors ps Log Mean Variance Count of Global FreqTable including Measurement Errors Ticks Log Mean Variance Count of Global FreqTable excluding Measurement Errors Ticks Reset Global FreqTable when writing a Log Entry Write output for Freq Table lines without matching entries Apply Setting to all Measurements Cancel Here we can define the name path of the log file Note that TTMViewer will never overwrite an existing file If it finds the filename already used it will append a counter to the filename MyStatistics dat becomes MyStatistics 2 dat or if that is already used too MyStatistics 3 dat up to MyStatistics 100 dat In addition to this TTMViewer supports macros in filenames and will substitute TIME DATE STARTCHN STOPCHN and COUNT or CNT with appropriate contents Note that macro names are case sensitive Furthermore we can choose how often TTMViewer will write its data and if logging is automatically started stopped when data collection is started stopped or if we wish to manually activate logging only when needed Next we have to select what information we want to log We can log the complete distribution table one line per used bin as well as statistical data Mean Variance SampleCnt measured in ticks of the chosen measurement mode and or in picoseconds TTMViewer generally eliminates measurement errors broken samples from the set of measurement results The
94. ntrl TTMViewer TTMUSserlO have been developed with Qt 4 8 however any newer version of Qt will probably require at most minor changes Note that you can download older versions of Qt from http download qt io archive qt If you look into the sources folder of the TTM8000 CD you will see various folders that contain actual source code for the provided applications and that are always used for all platforms and development tools and some folders that contain ready to use projects for specific development environments If you want to modify and or recompile the command line tools you should use the projects provided TTMTools VS2010 for Visual Studio 2010 TTMTools VS2005 for Visual Studio 2005 or TTMTools VS6 for legacy systems still using Visual Studio 6 If you want to work on the Qt based GUI tools and have installed the Qt tools as described above you can use the projects provided in TTMGUI VS2010 for Visual Studio 2010 or TTMGUI VS2005 for Visual Studio 2005 TTM Application development on Linux Under Linux there are many popular systems for building applications The TTM8000 Software supports a simple CMake and KDevelop 3 amp 4 CMake is a simple and highly portable system for building applications that is run from the command line You will fiind a ready to use project file in sources TTMApps CMake Just issue the command cmake CMakeLists txt to use cmake to create a makefile for all the applications and then use
95. o Connection Green Single Master Yellow Multiple Masters e Run Status of the Measurement currently in progress Off Ready No Measurement Green Measurement in Progress e Buffer Fill level of the TTM8000 internal timetag buffer Off Buffer Empty Green 1 49 filled Yellow 50 87 filled Red 88 100 filled e Error Error Status of the TTM8000 Off Ok Yellow The TTM8000 can not lock its internal clock to the provided reference clock Warning The TTM8000 will still provide measurement results however they will erroneous and should not be used Red The internal buffer of the TTM8000 has overflown The Error LED will become lit as soon as the buffer overflows and will remain lit until the next measurement is started e The LEDs A and B usually have no TTM8000 specific purpose and can be used by your application for whatever purpose seem appropriate They can be set using the TTMLib function TTMCntrl_c SetLEDs e C Heartbeat LED Flashing green to indicate that the TTM8000 is alive Buttons The TTM8000 features 2 buttons that control the configuration loaded during power up After booting is completed the buttons have no TTM8000 specific purpose and can be used by your application for whatever purpose seems appropriate They can be queried using the TTMLib function TTMCntrl_c QueryKeys e Pressing the button during power up forces the TTM8000 to boot the factory default firmware Thus a m
96. odule with broken firmware e g after a firmware upgrade gone awry can be made responsive again e Pressing the button during power up will cause the TTM8000s network to be configured with the factory defaults IP Addr 192 168 1 60 Netmask 255 255 255 0 This default network configuration remains valid until the next reboot only Thus once you can access your TTM8000 board with this default network configuration you will probably want to assign a permanent new network configuration using TTMCmd s command config network Press the button during normal operation to reset the TTM8000 board To prevent accidental resets you will need to hold down the button until all LEDs are red before the reset is actually performed TTM8000 6 60 Signal Inputs The Signal Inputs provide the actual timing signals Each input can either be used in high impedance mode or with a internal 500 termination resistor Add a simple jumper not an additional resistor to the termination connector of a given input to enable the internal termination e Start The Start Signal is used as time reference point by all Start Stop measurement modes i e all measurement modes but I Mode continuous e Stop 1 8 The Stop Inputs provided the signals whose timing is to be measured Stop1 and Stop2 are available for all measurement modes Stop3 to Stop8 are only available in I Mode and are inactive for all other measurement modes Back Panel Elements DC Power Supply
97. our measurement you can combine up to 16 TTM8000 boards to create measurements with up to 128 stop channels Since the clocks of all TTM8000 boards can be synchronized to each other they will not drift apart and all timestamps from all boards can be compared against each other There are however some limitations Even so the clocks of all TTM8000 boards are synchronized to each other every TTM8000 board uses its own PLL Phase Locked Loop to generate its own local high speed clock While the PLLs keep these clocks in sync in the long run there can be minor variations for short times that are evened out in the long run This oscillation of the PLLs around the optimal clock speed leads to an increased measurement jitter with the standard deviation of the timing measurements increasing by about 60ps Furthermore it becomes necessary to compensate the delays introduced by the cables used to distribute the Start signal Note that this is not much of an additional task Even with a single TTM8000 it was necessary to compensate the channel dependent delay introduced by the differences in operating speed of the sensors and the differences in the propagation delay due to the cables between the sensors and the TTM8000 Now we simply have another delay that contributes to the total delay between the external event and the creation of a timestamp in one of the TTM8000s For the overall compensation of these delays it is irrelevant how many partial delays contribute
98. owering on the TTM8000 and keep it pressed until the TTM8000 has finished booting This will cause the TTM to use the default IP address of 192 168 1 60 with a netmask of 255 255 255 0 This network configuration only remains valid until the next reset You should therefore connect to the TTM using the default configuration and assign a new permanent IP address e lcan ping the TTM8000 Module but TTMCmd and TTMCnitrl still won t find them The TTM8000 Software on the PC uses broadcast network packets to detect the TTM8000 Boards While this is perfectly harmless some firewalls and network security tools consider the response packets sent by the TTM8000 boards as unsolicited network traffic and silently discard the packets so that they never reach the TTM8000 Software and the boards remain undetected You can try explicitly stating the TTM8000 Modules IP address in the TTMCmd connect command e g ttmcmd x connect 192 168 1 60 This option is not supported in TTMCntrl or TTMViewer If that works you can be fairly certain that the network filter is the source of the problem Note When TTMCntrl and TTMViewer start their network communication the Windows Firewall will ask if this communication shall be permitted Beware Windows will suggest that this communication shall only be permitted within the Windows Domain but not at Home or Work or Public Place However if you have your TTM8000 Modules in a dedicated network rather than w
99. p a Ethernet interface under Linux please take a look at the chapter Setting up a Network interface under Linux in the appendix or ask your local system administrator Under Linux you can enable jumbo frames for network eth1 by using the command ifconfig eth1 mtu 8000 When running Linux the size of network buffers is limited by the value stored in Iproc sys net core rmem max You should provide at least 8 MByte rmem max 8388608 but 32 MByte don t hurt when operating at very high event rates Thus you can use echo 33554432 proc sys net core rmem max to immediately set the maximal size of the input buffer however your setting will be lost at the next reboot You can also add the line net core rmem max 33554432 to your letc sysctl conf file This change will survive reboots however the change will only become active at the next restart of the network interface So you will usually use both tricks together one to get immediate results and the other to make your change permanent All of the above performance hints require root administrator privileges Network Tuning for Windows On Windows Jumbo Frames can be enabled in the properties dialog of the network adapter LAN connection Properties Configure Advanced Jumbo Frames The default maximum buffer size under Windows is 1GByte and thus more than sufficient for TTM8000 Windows comes with the Windows Firewall that tries to identify and discard dangerous network pa
100. rite a Log Entry every 5 seconds Autostart stop Logging when Event Processing is started stopped Log Time of Day Log Date Log Single Event Frequency Log Number of Single Events since last Log Entry Log Number of Single Events since Start of Logging Log Coincidence Frequency Log Number of Coincidences since last Log Entry Log Number of Coincidences since Start of Logging Once we have completed our selection of logable events we can close the Configure Coincidence Logging dialog again and click the Write Log button to write the current state of the coincidence counters to a file assuming we have chosen Single Shot as repeat frequency or start repeated logging of the coincidence counters using the Start Log button and use the Stop Log button when we are finished The resulting file is tab seperated ASCII file that contains descriptive comments above each column and should be easy to process with the spreadsheet application of your choice or with your own self written tool If we actually need even vs odd pair coincidences then using the pair coincidence window is the easiest way to reach our goal However sometime we might want to detect coincidences of three or more events or compute pair coincidences of combinations of events other than odd vs even To do this we can use the Multichannel Coincidence window of TTMViewer To open this window click on the Show Multi Coinc button in TTMViewers Data Source d
101. rom the network via UDP by telling the TTM8000 module that we want to receive data from it Thus we shall select a Data Source of Module IP Addr and select the TTM8000 module just as we did when setting up the measurement in TTMCntrl As an alternative we could have selected a fixed UDP port on the local machine and expect that the TTM8000 be configured using e g TTMOCntrl to send its data there or we could have used a file with recorded data TIM Viewer Data Source Data Source Module IP Addr 192 168 1 60 TTM8000 ReScan Net Measurement Meas Mode No Data Received Received OByte Deadtime Filter Enable Deadtime Filter Retrigger Enable Stop1 0 0 ns op2 0 0 ns Stop3 0 0 ns Stop4 0 0 ns Stop5 0 0 ns Stop6 0 0 ns Stop7 0 0 ns Stop8 0 0 ns Channel Offset Adjustment Enable Channel Offset Adjustment Stop1 0 0 ns Stop5 0 0 ns oping Stop2 0 0 ns Stop6 0 0 ns Stop3 0 0 ns Stop 0 0 ns Stop4 0 0 ns Stop8 0 0 ns Single Event Filter Eliminate Events whose nearest neighbor is more than a 5000 0 ns ie v Forward Store Data Forward Store Data before or after applying the Deadtime Offset Adjustment and or Single Event Filter UDP Host IP Address 127 0 0 1 w Port 10503 File home lieger TimeTags Out dat Data Analysis Show Event Counters Cre
102. rself by touching the mounting screws of the back panel Analog Input Ports The TTM8000 features 4 analog input ports selectable unipolar 0 4 1V or bipolar 2V that have no TTM8000 specific purpose and can be used by your application for whatever purpose seems appropriate They can be queried using the TTMLib function TTMCntrl c GetADC the TTMUserlO application or the TTMCmd command get analogin Analog Output Ports The TTM8000 features 4 analog output ports 4 1V that have no TTM8000 specific purpose can be used by your application for whatever purpose seems appropriate They can be set using the TTMLib function TTMCntrl c SetDAC TTMUserlO application or the TTMCmd command set analogout Calibration Signals e Cal Out Calibration Out The TTM8000 contains a built in pulse generator that can generate Start and Stop pulses Calibration Out provides the generated Stop signal Note that this Stop signal is not internally connected to any Stop input Use an external cable to connect it to the Stop input of your choice e Start Out The Start signal is used as time reference point by all Start Stop measurements Depending on the configuration of the TTM8000 this can either be the signal from the Start signal input or the Start signal generated by the built in pulse generator The Start Out signal reflects the Start pulse used by the TTM8000s internal logic Use the TTMLib function TTMCntrl_c ConfigPulseGen
103. s a jitter of about 0 5ns around the center We shall remember both values TTMViewer can count coincidence between events on two or more channels however these coincidence counters expect that coinciding events have the same timestamps within some tolerance window Our events on channel 2 and 5 do however have an offset that we need to compensate before we can count coincidences We shall therefore enable the Channel Offset Adjustment feature in TTMViewers Data Source dialog Since the events on channel 5 arrive 7 6ns earlier than those on channel 2 we shall add 7 6ns to all timestamps on channel 5 and keep the timestamp from channel 2 and all other channels as they are Alternately we could have added 7 6ns to all timestamps on channel 2 and keep the timestamps of channel 5 as they are It s just the relative difference that is important TIM Viewer Data Source Data Source Module IP Addr 192 168 1 60 TTM8000 Re Scan Net Measurement Meas Mode No Data Received Received OByte Deadtime Filter Enable Deadtime Filter Retrigger Enable 4 n ES EN an Stop1 0 0 ns Stop2 0 0 ns 5 Stop3 0 0 ns Stop4 0 0 ns v w E RM L n P Lj p n StopS 0 0 ns Stopb 0 0 ns Stop 0 0 ns Stops 0 0 ns Channel Offset Adjustment Enable Channel Offset Adjustment Stop1 0 0 ns Stop2 0 0 ns Stop3 0 0 ns Stop4 0 0 ns Stop5 Stop6 0 0 ns Stop7 0 0 ns Stop8
104. s and want to look at single events Thus we shall leave all three filters disabled Our preparations are complete We can press Start in TTMViewer to begin receiving timetags We can press Start in TTMCntrl to start sending timetags AIT TTM Viewer TTM8000 Data Source Module IP Addr 192 168 1 60 TTM8000 Re Scan Net Measurement Meas Mode 1 8 Chn cont 82 3ps 64bit compressed Little Endian e g Intel x86 Alpha Received 11 22MByte 474 8KByte s Deadtime Filter Enable Deadtime Filter Retrigger Enable Stop 0 0 ns Stop2 0 0 ns B Stop3 0 0 ns Stop4 0 0 ns p Stop5 0 0 ns Stop6 0 0 ns I Stop7 0 0 ns Stop8 0 0 ns 00190 Channel Offset Adjustment Enable Channel Offset Adjustment Stop1 0 0 ns Stop2 0 0 ns Stop3 0 0 ns Stop4 0 0 ns rj Stop5 0 0 ns Stop6 0 0 ns f Stop7 0 0 ns Single Event Filter Eliminate Events whose nearest neighbor is more than 5000 0 ns Forward Store Data Forward Store Data before after applying the Deadtime Offset Adjustment and or Single Event Filter UDP Host IP Address 127 0 0 1 Port 10503 File homedieger Time Tags Out dat Data Analysis Create Cluster Histogram Show Event Counters Create Delay Histogram Show Pair Coinc Show Multi Coinc Save Config Load Config Stop
105. s even does not suit your needs please feel free to tailor the display of TTMViewer to match your requirements See PairCoincidences cpp PairCoincidences UpdateCounters The sources of TTMViewer are included in the software package you received with your TTM8000 As with histograms we can write the results from the pair coincidence window to a file for later processing First we shall select the way we log our data by clicking the Config Log button In the Configure Coincidence Logging dialog that pops up we can select the name of the logfile This filename can contain the macros DATE 96 TIME96 and CNT that will be replaced by appropriate data when the file is created Note Macro names are case sensitive Next we can select how often we want the pair coincidence data to be written to the file Finally we can select the contents of each line of logging information There is time of day and or date as definied by the PC s local clock and information for the single events and for the even vs odd coincidences For both singles and pair coincidences we can log the current frequency number of events within the last seconds before the log entry the number of events since the last log entry and or the number of events since the start of the coincidence measurement TTM8000 30 60 Configure Coincidence Logging Log File home ieger Pair Coincidence DATE96 96 CNT log Hint Use DATE TIME and CNT as wildcards W
106. se cross compilation on Windows or Linux If you are a Raspberry programmer you will probably have a cross compilation environment based on Eclipse on your desktop machine The TTM8000 Software Package contains a suitable Eclipse workspace at sources TTMTools Raspberry Note that since there is no Qt library for the Raspberry all TTM8000 applications that rely on Qt can not be used on the Raspberry You can only use the command line tools 53 60 TTM8000 Electrical and environmental specifications Supply Voltage 12 Vdc 8 to 14 Vdc 1 5 A 912 Vdc max 3 0 A peak Environment Operation Temperature min 5 max 35 Moisture max 8596 RH not condensing Environment Storage Temperature min 10 C max 80 C Moisture max 8596 RH not condensing Time Tagging and Clocks all inputs 5 5 all outputs LVTTL drive 500 Analog Signals input 4 5 4 5V output 4 4 V max load 4000 Digital I O inputs LVTTL max 3 3V outputs LVTTL max 10mA Power connector cable Use only LEMO connectors FGG 1B 302 CLADxx where xx depends on your cable diameter View from solder side of cable connector Pin 1 12 Vdc Pin 2 GND e External display connector cable optional Use only LEMO connectors FGG 1B 308 CLADxx where xx depends on your cable diameter on both sides of the cable The length of the cable to the external display is limited to 0 75 m Use only shielded cables with
107. solution 1 6ms Measurement Range Up to 16MEvents s per TTM8000 sustained 10 MEvents s per Channel sustained 180MEvents s peak Primarily intendend for internal use Hardware debugging Not recommended for end users e 32 8 Channels Rising and Falling Edges 82 3045ps Resolution 12 8ms Measurement Range Up to 16MEvents s per TTM8000 sustained 10 MEvents s per Channel sustained 180MEvents s peak Primarily intendend for internal use Hardware debugging Not recommended for end users e IStartStop 8 Channels Rising and Falling Edges 82 3045ps Resolution 6 4us Measurement Range Up to 25MEvents s per TTM8000 sustained 10 MEvents s per Channel sustained 180MEvents s peak e GMode 2 Channels Rising and Falling Edges 41 1523ps Resolution 65us Measurement Range RMode 2 Channels Rising or Falling Edges 27 4349ps Resolution 40us Measurement Range e MMode 2 Channels Rising or Falling Edges 27 4349ps MModeDiv Resolution 40us MModeDiv Measurement Range MModeDiv 1 31 In I G R Mode the Start input is permanently active In M Mode the Start input cannot be retriggered for a given duration lt Timeout gt after being triggered once Thus there is a tradeoff between max observable event frequency and max Start Stop interval set byteorder little endian little intel x86 big endian big powerpc 680x0 The TTM8000 hardware can deliver the timetag data in either little endian as used e g on x86 based Systems
108. ss and UDP port used by TTMViewer Assuming that no data is produced in the first place Are you sure your input signal is connected correctly The leftmost of the input jacks is the Start signal Stop1 is the second jack from the left If you use any 2 channel mode G R M Mode the Stop signals must be connected to Stop1 and Stop2 Stop3 Stop8 are disabled Are you sure you enabled the Active Signal Edges of your Start Stop inputs in TTMCntrl Only Active Edges produce events If you are using any of the Start Stop modes i e any mode that is not I Mode cont are you sure there was a Start pulse shortly before your Stop pulse TTMViewer freezes whenever a histogram window is open Are you measuring a signal that is highly aperiodic e g is randomly distributed and has a wide range of minimal maximal repetition rate and or is very fast Calculating a histogram that has lots many 1000 of used bins in TTMViewer is very expensive in terms of CPU power and will give the appearance of a frozen machine Most of this effort is wasted since the finite resolution of the screen allows only one bin pixel to be displayed You should therefore try to reduce the number of bins that are used by TTMViewer You can do so by using bigger bins incrementing BinSize without loss of visual precision due to the pixel limit As an alternative you can use a limited Time Range or a smaller Time Range if you are already using limits This approach reduces the num
109. ss 0xc000 You should now be able to ping the TTM8000 module ping 192 168 1 60 and get something along the lines of PING 192 168 1 60 192 168 1 60 56 84 bytes of data 64 bytes from 192 168 1 60 icmp seq 1 ttl 64 time 1 90ms 64 bytes from 192 168 1 60 icmp seq 2 ttl 64 time 0 24ms 64 bytes from 192 168 1 60 icmp seq 3 ttl 64 time 0 27ms TTM8000 58 60 Firewalls on Linux Once you can successfully ping your TTM8000 module you can try to discover the TTM8000 module using ttmcmd ttmcmd list If ttmcmd fails to discover your TTM8000 module there is a chance that the packets sent from the TTM8000 are blocked by the Linux network firewall usually based on iptables While most Linux systems come without a preconfigured firewall there is a growing over the years chance that a firewall is installed You can check your firewall configuration using sudo iptabl If the firewall is disabled thi Chain INPUT target Chain targe Chain target OUTPUT FORWARD prot pro les L p opt Source olicy ACCEPT opt source policy ACCEPT opt Source S will produce the following output policy ACCEPT prot Otherwise you can clear the firewall configuration using sudo sudo sudo sudo sudo iptabl iptabl iptabl iptabl iptabl es es es es es F t P P P nat F INPUT ACCEPT OUTPUT ACCEPT FORWARD ACCEPT 59 60 des d
110. stuck Use bigger and thus fewer bins and or use a limited observation window to reduce the number of active bins and reduce the stress on your CPU If we measure different signals or if the signal source suffers serious drift the diagram of the global distribution will become very wide possibly so wide that the current signal distribution is squeezed into a few pixels width To get a readable display in such a situation we can press the Reset button to reset the global distribution table We can also TTMViewer for long term measurements and have it write log files with statistical data that can later be evaluated with custom applications To do this we click on the Config Log button TTM8000 22 60 Configure Logging Log File nelnfo DATE96 96 STARTCHN STOP CHN CNT Jog Hint Use STARTCHN STOPCHN DATE TIME and CNT as wildcards Write a Log Entry every 5 seconds Autostart stop Logging when Event Processing is started stopped Log Current Frequency Table Log Mean Variance Count of Current FreqTable including Measurement Errors ps Log Mean Variance Count of Current FreqTable excluding Measurement Errors ps Log Mean Variance Count of Current FreqTable including Measurement Errors Ticks Log Mean Variance Count of Current FreqTable excluding Measurement Errors Ticks Log Global Frequency Table Log Mean Variance Count of Global FreqTable including Measurement Errors ps Log Mean Variance Cou
111. synchronization of multiple TTM8000s or other devices Threshold voltage for each trigger signal and external clock individually controllable 4 1V to accommodate a wide range of logic standards Each trigger input can either be high impedance or can be terminated with a 500 resistor Measurements results can compensate different source delays e g cable length 8 Digital I O Pins 3 3V for controlling external devices 4 Analog Outputs 4 1V and 4 Analog Inputs selectable 0 4 1V or 2V for controlling external devices Built In pulse generator for calibration e g cable length measurements Convenient TTMLib for easy problem specific application development with comprehensive sample code Ready to Use software for Linux Windows and Mac OS X GUI and command line oriented to get you started as quickly as possible The software is based on TTMLib and comes with full sources so that you can easily expand it to match your specific needs 5 60 TTM8000 8000 Hardware The 8000 Module features various connectors and user interface elements on its front and back panel Front Panel Elements Stop 1 Stop 8 LEDs The TTM8000 features 8 multicolored LEDs that indicate the Status of the TTM8000 e Link Status of the Ethernet network link Green Gigabit Ethernet link Yellow 100Mbit or 10MBit Ethernet link Red No Network e Status Status of the Connection to the TTM8000 Master Off N
112. the command make without any parameters to actually build the applications Most Linux distributions support KDevelop either in the default installation or easily installable from the standard repository KDevelop 3 was released in 2001 and was widely adopted as standard GUI for application developent under Linux KDevelop 4 was released in 2005 however since it was not compatible with its predecessor many people continued using KDevelop 3 for a long time after KDevelop 4 became available The TTM8000 Software Package provides preconfigured projects for both KDevelop 3 amp 4 If you choose to use KDevelop 3 there is a project file for the command line tools TTMCmd TTMCnvt TTMMerge at sources TTMTools KDevProj TTMTools kdevelop To build the GUI based tools TTMCntrl TTMViewer use the project file at sources TTMGUI KDevProj TTMGUI kdevelop If you prefer KDevelop 4 there is a project file for all TTM8000 tools both command line oriented and graphical at sources TTMApps KDev4Proj TTMApps KDev4Proj kdev4 TTM8000 52 60 TTM Application development on Mac OS X Apple provides the free XCode development environment for OS X XCode used to be installed automatically with earlier releases of OS X then Apple switched to putting XCode on the DVD with OS X but not installing it with the default installation and currently Apple does not ship any DVDs any more and requires XCode to be downloaded and installed by the user It is a
113. to the total delay for each channel or how long each partial delay actually is Its just the total delay that needs to be determined and compensated for So having an additional contributor does not make thing more tricky We shall now demonstrate how two TTM8000 boards can be cooperatively measure some signals For our demonstration we will use two TTM8000 boards and two short SMB cables that will provide synchronization between the boards and use the built in signal generators of the TTM8000 Boards as measurement target signals We want to connect the output of a single signal generator to two Stop inputs We need to use an active signal splitter here that accepts the signal with proper 500 termination and produces two copies using two independent drivers so that the resulting signals will have nice steep edges and little overshoot when terminated at the 500 Stop inputs of the TTM8000 Using a simple Y cable to split the signal into two copies will cause serious degradation of signal quality due to impedance mismatches and resulting signal reflections This may lead to duplicate missing detection of events or best case serious degradation of signal edges causing more timing jitter Using an active signal splitter is therefore highly recommended If you don t have an active signal splitter you can generate a reference signal using a signal generator that has two complementary outputs and modify the setup of the measurement to trigger on the risin
114. ulsegen start lt FrameCnt gt lt FrameLen gt lt StopPos gt lt BurstCnt gt BurstDelay lt SendFirstStart gt lt SendNextStart gt stop The TTM8000 contains a pulse generator that can be used for calibration The pulse generator can create a sequence of frames Each frame has a given length in multiples of 8ns begins with an optional pulse to the Start output and after a suitable delay an optional burst of pulses to the Calibration Output The Start pulse is sent at frame time 0 and can be individually enabled disabled for the first frame and all other frames The burst of Calibration pulses starts at frame time StopPos 8ns Select StopPos gt FrameLen if you don t want pulses on the Calibration output The Burst will consist of BurstCnt pulses that are BurstDelay 8ns apart Each pulse is 8ns wide Thus if BurstDelay is equal to one there is no time between two pulses and the burst of pulses merges into one long pulse The pulse generator will stop automatically after FrameCnt frames have been sent and can be stopped earlier by explicitly sending a stop command wait until pulsegen done Delay script execution until the pulse generator is done wait until while key keystate lt Keylndex gt 0 up released 1 down pressed Delay script execution until the state of the button on TTM8000 matches the given condition The Keylndex can be either 0 or 1 If no Keylndex is provided Ke
115. ution The TTM8000 constantly monitors the levels on all the external inputs and when it detects a transition low to high or high to low on any input it records the number of the input the direction of the transition and the current value of the high resolution clock in an event table inside the TTM8000 The contents of this event table is then sent via standard Gigabit Ethernet UDP IP to a connected PC Windows Linux Mac where the events are then processed by suitable software e g to detect patterns in the recorded events 12 1 5GHz Internal Clock Ads Fi start 1 Ethemet Signal X Stopt FL stop2 gt Stop3 E e Signal Y Elsta amp gt Stops Channel Edge TimeStamp 60bit gt Stop amp 8 Rise 13022 1 Rise 13024 8 Fall 13025 gt Stop 1 Fal 13026 3 Rise 13080 n 3 Fal 13032 Signal 2 Stops 8 Rise 13035 Eug iso 13037 While it is possible to record all edges on all eight inputs it is not mandatory to do so The 8000 be fully configured to record only selected edges for selected inputs thus drastically reducing the number of entries in the event table and thus drastically reducing the effort needed to process the table Furthermore the definition of high and low signal levels can be configured individually for each external input to directly process signals from many different logic families The TT
116. vailable at https developer apple com xcode downloads XCode is all you need if you just want to compile the command line tools TTMCmd TTMCnvt TTMMerge If you want to build the GUI tools TTMCntrl TTMViewer TTMUserlO too you will additionally need to download and install Qt It is available from http www gqt io download open source If you look into the sources folder of the TTM8000 CD you will see various folders that contain actual source code for the provided applications and that are always used for all platforms and development tools and some folders that contain ready to use projects for specific development environments If you want to modify and or recompile the command line tools you should use the project provided in TTMTools XCodeProj Just open the provided XCode project within and you should be able to compile and run all the provided command line applications If you want to work on the Qt based GUI tools and have installed the Qt tools as described above things are a little bit more tricky since the XCode projects needed to create Qt applications can create a single application at a time only and furthermore contain lots of absolute paths in the project which make it impossible to transfer a project from one Mac to another Thus it is necessary to build the XCode project files locally on the development machine To do so open a console window and change to the folder sources TTMOCntrl XCodeProj Despite its name this folder
117. wever some triggers might be ignored or we can abort the current cluster and start a new cluster thus the number of clusters matches the number of triggers however some clusters might be shorter than the specified window width or we can extend the current cluster thus a new cluster is started whenever a trigger events arrives after a break of at least WindowLength Beware If no such break occurs the current cluster will never end and no results will ever be displayed 33 60 TTM8000 If we have chosen to use a external trigger event to start a cluster we must define which event or events we want to use as triggers If we simply split the time in slices we don t need and can not configure an external trigger time passes by itself Finally we need to decide which event s we want to count when measuring the activity in a cluster Note that itis OK to use the same events to start a cluster and as countable cluster events Once TTMViewer starts receiving events they will automatically be grouped into clusters as defined above and the Cluster Histogram will show the distribution of the number of events in a cluster As with all the other displays it is once again possible to write the results to a log file for later processing by a custom application TTM8000 34 60 Sample Application Using Multiple TTM8000 boards If you have a large measurement setup and the 8 stop channels of a single TTM8000 board are not sufficient for y
118. where we will run TTMViewer to visualize the data stream Remember to save your changes Now run the following command ttmmerge f path merge cmd to start TTMMerge and of course we need to restart our data source ttmcmd f path mstart cmd TTMMerge will now collect the data and send the to the selected network port We can verify this by starting TTMViewer and setting it to collect its data from the UDP port chosen above The Event Counter Window of TTMViewer makes it easy to see that the events of all three connected inputs were combined into a single stream by TTMMerge and sent to TTMViewer If no data arrives at TTMViewer you should first check if TTMMerge does indeed process data TTMMerge constantly displays the amount of data processed since the start of the application and within the last second on its terminal window so you can check liveness there If TTMMerge does not process and data connect TTMViewer directly to the TTM8000 boards to see if data is produced Note attaching a TTMViewer to the TTM8000 breaks the connection to TTMMerge so you will need to restart TTMMerge after closing or disconnecting TTMViewer If data is produced and processed by TTMMerge but not visible in TTMViewer then there is probably a mismatch between the target IP address as stated in Step5 of TTMMerge cmd and the IP address that TTMViewer tries to read its data from Now that we have all timetags in a single stream TTMViewer we can of course use
119. wo event sources to two input channels of the TTM8000 In our demonstration we shall use channels Stop2 and Stop5 Any other combination would work fine for the first part of this demonstration however for the second part we need an even and an odd numbered channel Now that the primary hardware setup is complete we can start TTMOCntrl to configure our measurement TTMOCntrl will automatically search for available TTM8000 devices on all network interfaces of your computer and will list all discovered devices in the drop down menu As in the previous application shall select our Timetagging Module and and Connect to it We choose a Measurement Mode of I Mode 8 Chn cont 82 3ps 64 bit compressed and a Byte Order of Little Endian e g Intel x86 Alpha Note that Measurement Modes other than I Mode Continuous are not currently supported by the Correlation Counter Window Time Tagging Control Center Time Tagging Module Module IP Addr 192 168 1 60 TTM8000 Re Scan Net Connect vos Measurement Meas Mode I Mode 8 Chn cont 82 3ps 6dbit compressed Byte Order Little Endian e g Intel x86 Alpha Signal Input Level Signal Delay Compensation Advanced E V Advanced Config Active Signal Edges Start Stop Stop2 Stop4 Stop5 Stop6 Stop Rising Edge Falling Edge Data Destination Host IP Addr Receiver Req v F
120. ylndex will be assumed to be 1 wait until keyevent lt Keylndex gt release press Delay script execution until the button on the TTM8000 changes in a given way The Keylndex can be either 0 or 1 If no lt Keylndex gt is provided lt Keylndex gt will be assumed to be 1 wait until while DigitallOIn Mask Value Delay script execution until the state of the DigitiallOs match a given condition config fpga File Update the TTM8000 FPGA Image The update becomes active after the next power cycle config firmware File Update the TTM8000 PowerPC Firmware The update becomes active after the next power cycle config network name lt BoardName gt ipaddr lt IP Addr gt lt Port gt netmask lt NetMask gt Define the network configuration of the TTM8000 config clocksynth useexternclockout true false externclockoutfreq lt Freq gt Hz kHz MHz useexternclockin true false externclockinfreq lt Freq gt Hz kHz MHz externclocklevel Level mV V The TTM8000 contains a clock synthesizer that will generate the reference clock for the TTM8000 it can either be driven from an internal crystal or from an external reference clock running at 10 20 40 or 80MHz Besides generating the clock needed for the operation of the TTM8000 the clock synthesizer can also generate an external output clock at 10 20 50 100 200 or 500kHz or 1

TTM8000 - Roithner Lasertechnik

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