ADC-200 Series User`s Guide
Contents
1. The adc200 vi module in the Examples subdirectory shows how to access these routines To use this example Copy adc200 vi and adc20032 d11 to your LabVIEW user 1ib directory Use LabVIEW to open the adc200 vi Select the printer port to which your ADC 200 is connected Press RUN Note for the ADC 216 you will need to alter the scaling in frame 7 by replacing 2 048 by 32 768 Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 29 Glossary Glossary AC DC Switch The AC DC switches for the ADC 2xx operate under software control rather than manually ADC Analog to Digital Converters capture analog data and convert it into digital data for storage and further processing Channel This specifies which channel to measure data from A and or B Equivalent Time Sampling ETS Some products support Equivalent Time Sampling ETS which offers a higher effective sampling rate when used with repetitive signals Note that ETS should not be used for one shot or non repetitive signals Range This allows you to specify an input voltage range adc200 en r4 Copyright O 1995 2015 Pico Technology Ltd All rights reserved UK headquarters Pico Technology James House Colmworth Business Park St Neots Cambridgeshire PE19 8YP United Kingdom Tel 44 0 1480 396 395 Fax 44 0 1480 396 296 sales picotech com support picotech com www picotech com adc200 en r2. adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 26 3 2 27 adc200 set ets void adc200 set ets unsigned short interleave unsigned short max cycles unsigned short mode This function is used to enable or disable ETS and to set the ETS parameters Arguments interleave Specifies the number of ETS interleaves to use If the ETS sample time is 20 ns and the interleave is set to 10 the approximate time per sample will be 2 ns max cycles Specifies the number of cycles to store the computer can then select interleave cycles to give the most uniform spread of samples Max cycles should be between two and five times the value of interleave mode ETS OFF disables ETS ETS SLOW enable ETS and provide data every max cycles cycles ETS FAST enable ETS and provide data every interleave cycles ETS SLOW takes longer to provide each dataset but the datasets are more stable and unique Returns Nothing 3 2 28 adc200 set frequency long adc200 set frequency long frequency This routine controls the signal generator If the frequency is zero the signal generator is turned off If the frequency is between 1 and 250 000 the driver starts the signal generator at the nearest available frequency The returned value is the actual frequency Note The signal generator stops if you call any routine other than adc200 ready Arguments frequency The required
3. 3 2 8 adc200_set_channels unsigned short adc200_set_channels A200_MODE mode This routine defines whether the ADC 2xx is to collect data from one or from both channels It returns the number of channels 1 or 2 if successful otherwise it returns zero See the product specifications for the sampling rates of each product in one and two channel modes Arguments mode O A200_CHANNEL_A channel A only 1 A200_CHANNEL_B channel B only 2 A200 BOTH CHANNELS both channels Returns Number of channels 1 or 2 if successful otherwise it returns ZERO 3 2 9 adc200_set_oversample unsigned short adc200_set_oversample unsigned short factor This routine specifies the number of measurements to take for each reading As the oversample factor increases the maximum sampling rate and the maximum number of samples per block decreases Arguments factor The oversample factor must be a number between 1 and 16 Returns FALSE if oversample factor is out of range Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 15 Driver formats amp routines 3 2 10 adc200_set_timebase unsigned short adc200_set_timebase unsigned long ns unsigned char is_slow A200_TIME timebase This routine is used to specify the time interval between readings Arguments ns This is the time interval in nanoseconds between readings at the selected timebase is_slow This is always s
4. 6 LabVIEW cacos tsc saaaaaad 28 DGIOSS RO 29 Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 Introduction 1 1 1 Introduction This manual covers the ADC 200 ADC 212 and ADC 216 products Where information applies equally to all three product groups the abbreviation ADC 2xx is used The ADC 2xx products are high speed analog to digital converters ADCs with two input channels and software controlled input ranges They can be used as PC based oscilloscopes spectrum analyzers with the supplied PicoScope software or as data loggers with the PicoLog software alternatively you can use the ADC 2xx driver software to develop your own programs to collect and analyze data from the unit The ADC 2xx package contains the following items ADC 2xx unit 25 way parallel port cable power supply 12 volt 9 500 mA software CD installation guide Connecting to the PC The ADC 2xx can be connected to the PC in two ways directly to a parallel port printer port on the computer to a USB port on the computer via a Pico USB parallel port adapter Parallel port operation When you install the application software from the Pico CD the computer will ask you which port to use Select LPT1 LPT2 or LPT3 Note you can change the port at a later stage if you need to To use the ADC connect it to the parallel port on your comp
5. Arguments enabled This is TRUE to enable rapid repeat mode FALSE to disable it Returns Nothing The following example shows how to collect 50 blocks of 100 samples Note that the first call to adc200_run will take 50 to 100 ms longer than subsequent calls adc200_set_rapid TRUE for 1 1 1 50 AFF adc200_run 100 while adc200_ready adc200 stop 0 adc200 get values buffer adc200_set_rapid FALSE Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 19 Driver formats amp routines 3 2 14 adc200 max samples unsigned long adc200 max samples void This routine returns the maximum number of samples that you can ask for This is affected by a number of factors ADC 2xx model Channel mode single dual Oversampling factor Trigger delay Therefore call this routine after you have selected the parameters listed above Arguments None Returns Maximum number of samples as a long integer The ADC 2xx operates so fast that it takes a couple of hundred readings to start and stop the converter The buffer is allocated in blocks of up to 512 bytes one after the other block size depends on the type and speed of the product Depending on when the trigger condition is reached and what trigger delay is specified some of the data will not be used This unused data can be up to 511 bytes per channel The following formula can be used to
6. between the trigger event and the corresponding sample Times before the trigger event are negative and times after the trigger event are positive buffer_a a pointer to the buffer to put data from channel A into It is unused if the ADC is collecting only from channel B buffer_b a pointer to the buffer to put data from channel B into It is unused if the ADC is collecting only from channel A no_of_values The maximum number of data values to transfer Returns Nothing In non ETS mode the samples will always be evenly spaced If for example you were to request 10 samples with 20 pre trigger and 20 ns per sample the times buffer might contain the following 40 20 0 20 40 60 80 100 120 140 adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 22 3 2 20 adc200 get overflow short adc200 get overflow short channel This routine determines whether an overflow occurred the input voltage went above or below the limits of the selected range on the specified channel Arguments channel 0 channel A 1 channel B Returns TRUE if an overflow occured otherwise it returns FALSE 3 2 21 adc200 get single void adc200 get single short far buffer This routine starts the ADC 2xx collects a small number of samples and then returns the average of these samples Arguments buffer A pointer to a buffer containing two integers On
7. approximate the maximum number of samples available max sample buffer size 1000 oversample For some 8 bit units the same channel can be routed to both memory banks so the effective number of samples is doubled 3 2 15 adc200 run unsigned short adc200 run unsigned long no of values This routine tells the ADC 2xx to start collecting data Arguments no of values In Fast mode this is the number of data values that you require Returns TRUE if the ADC 2xx is started successfully otherwise it returns FALSE adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 20 3 2 16 adc200_ready unsigned short adc200_ready void Arguments None Returns TRUE when the ADC 2xx has collected a complete block of data otherwise it returns FALSE 3 2 17 adc200 stop void adc200 stop void Call this routine to stop the ADC 2xx If you call it before a trigger event occurs the ADC 2xx may not contain valid data Arguments None Returns Nothing 3 2 18 adc200 get values void adc200 get values short huge buffer a short huge buffer b unsigned long no of values This routine gets data from the ADC 2xx For the ADC 200 and ADC 212 zero corresponds to zero volts 2047 and 2047 correspond to the maximum and minimum voltage on the currently selected range For the ADC 216 zero corresponds to zero volts 32767 and 32767 correspond
8. frequency in hertz Returns Actual frequency of the signal generator Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 27 Programming support 4 1 4 2 Programming support C Windows There are two C example programs one is a very simple GUI application and the other is a more comprehensive console mode program that demonstrates all of the facilities of the driver The GUI example program is a generic windows application ie it does not use Borland AppExpert or Microsoft AppWizard To compile the program create a new project for an Application containing the following files a200test c a200test rc adc20032 1ib Borland 32 bit applications or adc200ms 1ib Microsoft Visual C 32 bit applications The following files must be in the compilation directory a200test rch adc200 h and the following file must be in the same directory as the executable adc20032 d11 all 32 bit applications The console example program is a generic windows application ie it does not use Borland AppExpert or Microsoft AppWizard To compile the program create a new project for an Application containing the following files a200con c adc20032 1ib Borland 32 bit applications or adc200ms 1ib Microsoft Visual C 32 bit applications The following files must be in the compilation directory adc200 h and the following file must be in the same directory as the executable adc20032 d11
9. to support the current DLL The USB adapter cannot be found on the port number supplied to the most recent call to adc200 open unit The USB adapter cannot be configured Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 25 Driver formats amp routines 3 2 24 3 2 25 3 2 26 adc200_get_product short adc200_get_product void Arguments None Returns value which indicates what type of ADC 2xx is attached value Type of ADC 0 No ADC attached 200 ADC 200 8 bit converter but the driver returns 12 bit values 212 ADC 212 12 bit converter 216 ADC 216 16 bit converter adc200_get_max_ets unsigned short adc200_get_max_ets void Arguments None Returns Maximum interleave factor that can be used for ETS If the ADC 2xx unit does not support ETS it will return ZERO With the ADC 212 50 amp ADC 212 100 it will return a value of 100 adc200_get_ets_time unsigned long adc200_get_ets_time void Arguments None Returns Sample time that will be used in ETS mode When ETS is selected the effective sample time will be the returned sample time divided by the interleave factor For example if the ETS sample time is 20 ns an interleave factor of 10 would give samples approximately every 2 ns The time value is in the time units specified in the most recent call to adc200_set_time_units the default is nanoseconds Use adc200_set_ets to enable disable ETS
10. to the minimum and maximum voltage on the currently selected range In Fast mode this routine reads in the whole block of data from the ADC 2xx The number of readings returned are put into the buffer Arguments buffer a a pointer to the buffer to put data from channel A into It is unused if the ADC is collecting only from channel B buffer b a pointer to the buffer to put data from channel B into It is unused if the ADC is collecting only from channel A no of values The maximum number of data values to transfer Returns Nothing Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 21 Driver formats amp routines 3 2 19 adc200_get_times_and_values void adc200_get_times_and_values long huge times short huge buffer_a short huge buffer_b unsigned long no_of_values This routine gets samples and the times that samples were taken from the ADC 2xx By default the time is in nanoseconds the function adc200_set_time_units can be used to select other time units for example microseconds For the ADC 200 and ADC 212 zero corresponds to zero volts 2047 and 2047 correspond to the maximum and minimum voltage on the currently selected range For the ADC 216 zero corresponds to zero volts 32767 and 32767 correspond to the minimum and maximum voltage on the currently selected range Arguments times a pointer to the buffer for the times Each time is the interval
11. 24 3 2 23 adc200 get status short adc200 get status void This routine returns the status from the most recent call to adc200 open unit Arguments None Returns code representing the status of the ADC 2xx The codes are defined in ADC200 h code status 0 A200 OK 1 A200 INVALID PORT 2 A200 INVALID HW VERSION 3 A200 INVALID SW VERSION 4 A200 CONFIG FAILED 5 A200 ADDR READ FAILED 6 A200 NVR FAIL 7 A200 UNIT NOT FOUND 8 A200 INVALID LENGTH 9 A200 DRIVER NOT FOUND 10 A200 OLD DRIVER VERSION 11 A200 USB ADAPTER NOT FOUND 12 A200 USB ADAPTER NOT CONFIGURED description All is ok The port number supplied to the most recent call to adc200 open unit is unavailable or invalid The version of the ADC2xx hardware is not recognised by the driver The version of the ADC 2xx firmware is not recognised by the driver The ADC 2xx cannot be initialised properly The ADC 2xx cannot be initialised properly The unit s internal calibration information has been corrupted The ADC 2xx cannot be found on the specified port This is for Pico internal use only Contact Pico Technical Support if this error occurs The adc200 sys pico vxd or pico 386 drivers cannot be found or have not been initialised The adc200 sys pico vxd or pico 386 drivers is to earlier a version
12. 2xx unit Find out whether the ADC 2xx has software controlled AC DC switches Set the AC DC switch Set the input voltage range Specify channels to use A B Both Specify the oversample factor Set the time interval between samples Set the units for times default ps Specify the triggering parameters Enable rapid block repeat mode Find out how many samples can be taken using current settings Start the ADC 2xx collecting data Find out whether the ADC 2xx has collected some data Stop the ADC 2xx Get a block of samples from the ADC 2xx Get a block of samples and the times at which they were taken Determine whether an overflow occurred during the last adc200_get_values operation Get a single value from each channel If open failed get fault info If open succeeded get unit details Get the error code from the most recent adc200_open_unit operation Find out what type of unit 200 212 216 is connected Get the maximum ETS interleave Get the time per sample in ETS mode Set ETS parameters Controls the signal generator The C sample program a200con c show how to use all of the functions of the driver and includes examples showing each mode of operation This is the general procedure for reading and displaying a block of data open the ADC 2xx stop the ADC 2xx E240 pl Oy UI CU INS E 0 display the data select ranges until the required mV range is located set AC DC switches channels trigger and overs
13. 4 2015 09 11 USA headquarters Pico Technology 320 N Glenwood Blvd Tyler Texas 75702 United States Tel 1 800 591 2796 Fax 1 620 272 0981 Copyright 1995 2015 Pico Technology Ltd All rights reserved
14. Technology ADC 200 212 216 PC Oscilloscopes User s Manual adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved Contents Contents A 1 1 Connecting to the PC sscsssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssscscssees 2 Safety Warning 2 Product features E ORNATO 4 UDPDUIDCUDD P RE 2 Equivalent Time Sampling ETS ccccccccccccssssssssssssssssscscccssessssssssssssssssssssssssssssssssssssssssssssssssssssssses D 3 Principles of operation D 3 Driver tormats amp routines 5 ia 8 E O Windows 32 bit driver e SSES 10 IRAN NO 10 LE GILT 12 5 adc200_has_relayS 12 b ade 200 se di A AAA Sian 12 7 adc200 set range 13 BAC ZOO set channels insistas asas 14 jEn 14 10 ade200 set tiniehas et CD L EE 15 T Pade 200 set tine Units AAA AAA AAA REF skin thinkin in EUN XXE EUR EO EN EO FUE Ea Eada 16 12 adc200 set trigger 17 13 adc200 set rapid AAA A 18 A anda 19 15ade200 CON sa a a DD Sadr 19 16 adc200 ready AAPP RNA 20 17 a
15. _run ready FALSE while not ready adc200_set_unit 1 ready adc200_ready adc200_set_unit 3 ready ready amp adc200_ready adc200_set_unit 1 adc200_get_values adc200_set_unit 3 adc200_get_values adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 3 Driver formats amp routines Formats The drivers are available in two formats Windows XP Vista DLL Linux driver Functions The driver contains the following functions Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 Driver formats amp routines Function adc200 get driver version adc200 open unit adc200 set unit adc200 close unit adc200 has relays adc200 set dc adc200 set range adc200 set channels adc200 set oversample adc200 set timebase adc200 set time units adc200 set trigger adc200 set rapid adc200 max samples rt adc200_run adc200_ready adc200_sto adc200_get_values adc200_get_times_and_values adc200_get_overflow adc200_get_single adc200_get_unit_info adc200_get_status adc200_get_product adc200_get_max_ets adc200_get_ets_time adc200_set_ets adc200_set_frequency Sequence of calls Description Determine the driver version Open an ADC 2xx unit Switch to the ADC 2xx on a different port multi unit operation only Shut down an ADC
16. all 32 bit applications Visual Basic Versions 4 and 5 The Examples subdirectory contains the following files adc20032 vbp project file adc20032 bas procedure protypes adc20032 frm form and program Note The routines which return a TRUE FALSE value return 0 for FALSE and 1 for TRUE whereas Visual basic expects 65 535 for TRUE Check for gt 0 rather than TRUE adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 28 4 3 4 4 4 5 4 6 Delphi The program adc200 dpr demonstrates how to operate the ADC 2xx The file adc200 inc contains procedure prototypes that you can include in your own programs This has been tested with Delphi versions 1 2 and 3 The following files are also supplied adc200fm dfm adc200fm bas Excel Excel 7 Office 95 etc 1 Load the spreadsheet adc20032 x1s 2 Select Tools macro 3 Select getadc200 4 Select Run Note The Excel Macro language is similar to Visual Basic The routines which return a TRUE FALSE value return 0 for FALSE and 1 for TRUE whereas Visual basic expects 65 535 for TRUE Check for gt O rather than TRUE Agilent Vee The example routine adc200 vee is in the Examples subdirectory It uses procedures that are defined in adc200 vh It was tested using HP Vee version 5 under Windows 95 LabVIEW The routines described here were tested using LabVIEW for Windows 95 version 4 0
17. ampling select timebases until the required ns per sample is located set the signal generator frequency if required start the ADC 2xx running wait till the ADC 2xx says that it is ready transfer the block of data from the ADC adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 10 3 1 3 1 1 3 2 3 2 1 Driver formats Windows 32 bit driver The Windows XP Vista driver adc200 sys is installed in Windows This file is normally loaded when you install the software To check that the driver is loaded Press the Start button Select Settings Select Control panel Select System Choose the Device manager tab Check that ADC 2xx is present and marked as started Oe qu If not check that the driver is present and then use the regdrive exe program which is copied into the Pico directory Type in regdrive adc200 The Windows 32 bit drivers are accessed using the file ADC20032 DLL which is installed in the Examples subdirectory The DLL uses STDCALL linkage conventions and undecorated names Note The Windows XP Vista driver does not have access to the actual base addresses for the parallel ports It assumes that they are LPT1 0x278 LPT2 0x378 LPT3 Ox3BC If your computer does not conform to this standard you should enter the port number corresponding to the actual port base address in the adc200 open unit call Linux driver See the man i
18. d adc200_set_trigger unsigned char enabled A200_TSOURCE source A200_TDI A200_TDELAY delay_percent short R direction threshold This routine defines a trigger event and specifies what data block to collect with respect to the trigger Arguments enabled Source direction delay_percent threshold Returns Nothing This is TRUE if the ADC 2xx is to wait for a trigger event and FALSE if the ADC 2xx is to start collecting data immediately O A200 TSOURCE A 1 200 TSOURCE B 2 A200 TSOURCE E I ES use external logic input as trigger O A200 RISING 1 200 FALLING This specifies the delay as a percentage of the block size between the trigger event and the start of the block It should be in the range 100 to 10096 Thus 0 means that the first data value in the block and 5096 means that the trigger event is in the middle of the block This is the threshold at which a trigger event on channel A or B takes place It is scaled in ADC counts adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 18 3 2 13 adc200 set rapid void adc200 set rapid unsigned short enabled This routine enables rapid repeat mode where the driver initialises the ADC 2xx only once then several blocks can be collected in rapid succession Block repeat rates of 200 per second are possible
19. dc200 stop secsecessesccecesrssrcsseseeecsencsssseccessessseecensessseesenseessesensesssenssessenseasensseasenssenseasenseensensessesseasesssensensesssensenseees 20 18 adc200 get values 20 19 adc200 EUPn 21 20 adc200 get overflow scsscssssessssssesessesssesseseecsssssesssesessssssceesesssesseeceescessessesssesesssessesssesesssonsesssecsssonsescssseessonsens 22 j 22 23 23 adc200 get status 24 24 adc200 25 j 25 A iae 25 27 dc200 set AAA UR TD PODER EE 26 adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide jEOA 26 4 Programming AAA tex ue teet eite ee tease RU Mire petes uy 27 1 C Windows p 27 IDEAR 27 rail 28 A Excel 28 jw A eiee 28
20. e between O and 255 to represent the currently selected voltage range To facilitate software development the numbers are adjusted so that 0 ADC counts corresponds to O volts All values returned by the driver are scaled as if 16x oversampling is selected so the maximum positive voltage in the selected range is represented by 2047 and the maximum negative voltage by 2048 The ADC 212 is a 12 bit ADC which returns a value between 2047 and 2048 regardless of the oversampling selected The ADC 216 is a 16 bit ADC which returns a value between 32767 and 32768 Signal generator The ADC 2xx has a built in signal generator which may be set using adc200_set frequency It produces a selection of accurate frequencies from 1 kHz to 250 kHz These are selected under software control The waveform is approximately square at low frequencies but it rounds off above about 100 kHz The signal generator output is the same as the signal generator input so these two functions cannot be used at the same time Multi unit operation It is possible to collect data using up to three ADC 2xx units at the same time Each ADC 2xx must be connected to a separate parallel port The routine adc200_set_unit select which unit the driver should access next For example to collect data from units on LPT1 and LPT3 at the same time adc200_open 1 adc200_open 3 adc200_set_unit 1 set up unit 1 adc200_run adc200_set_unit 3 set up unit 3 adc200
21. e calculated as adc200_get_ets_time adc200_get_max_ets For example for a 20 ns sample time and max interleave of 100 the minimum equivalent sample time is 200 ps which corresponds to 5 GS s Notes 1 When using ETS the samples are not evenly spaced The use of adc200_get_times_and_values rather than adc200_get_values is therefore essential 2 When ETS is enabled adc200_set_timebase is ignored Principles of operation This section explains how the ADC 2xx works This information is intended for people writing their own software and is not required if you are only using the product with PicoScope or PicoLog software The ADC 2xx range includes both high speed analog to digital converters eg ADC 200 100 and high resolution converters eg ADC 216 These devices take sequences of voltage measurements and feed the information into a computer Block sampling When running at high speeds the ADC 2xx can collect data much faster than the PC can read it so the ADC 2xx reads in a block of data into internal memory then transfers it to the PC once the block is completed At very low speeds it may be unacceptable to wait until the block is completed before being able to inspect the first few readings Therefore in addition to the Fast mode the driver routine adc200_get_single is provided to obtain single readings adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Seri
22. er positive Dimensions mm 140 x 190 x 45 Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 Product features 2 2 2 3 Equivalent Time Sampling ETS Equivalent time sampling ETS is a way of increasing the effective sample rate when working with repetitive signals It is not possible to use ETS with one shot signals ETS works because the trigger event can be assumed to be asynchronous with respect to the sampling clock If the unit collects blocks of data from 100 successive trigger events there should be a reasonable spread of time intervals between the trigger event and the next sample If the unit records this time interval from each cycle the computer can interleave the samples from successive blocks to give approximately 100 times the sampling rate Because the time interval between the trigger event and the next is somewhat random there is likely to be bunching in some areas and gaps in others In order to get a reasonable distribution it is necessary to collect say 300 blocks then to select the best 100 from them ETS is managed using three routines adc200_get_max_ets this indicates the maximum number of ETS interleaves allowed it will be zero if the particular unit in use does not support ETS adc200_get_ets_time get the time per sample when running in ETS mode adc200_set_ets set the interleave and max cycles The minimum equivalent sample time can b
23. es User s Guide 6 Fast mode In fast mode the computer starts the ADC 2xx to collect a block of data into its internal memory When the ADC has collected the whole block the computer stops the ADC and transfers the whole block into computer memory The maximum number of values depends upon the size of the ADC 2xx memory The unit can sample at a number of different rates which are the clock frequency divided by powers of two half quarter eighth etc There are between 16 and 20 sampling rates depending on the ADC 2xx model There is a separate buffer for each channel on the faster models one input can be routed into both buffers thus doubling the effective sampling rate The ADC 2xx driver normally performs a number of setup operation before collecting each block of data This can take up to 50 milliseconds If it is necessary to collect data with the minimum time interval between blocks use the adc200_set_rapid option adc200_get_single The adc200_get_single routine provides a way of collecting a single reading averaged from a number of samples This can be used instead of Fast mode where the screen needs to be updated regularly Triggering The ADC 2xx can either start collecting data immediately or it can be programmed to wait for a trigger event to occur with the adc200_set_trigger routine The trigger event can occur when the channel A or B input crosses a threshold voltage or ona change of state of the exter
24. et to FALSE by the driver timebase a code between 0 and 19 not all codes are valid for all units check the return value Timebase 0 is the fastest timebase Timebase 1 is twice the time per sample Timebase 2 is four times etc Returns If the requested timebase is valid this routine returns TRUE and sets the variable ns otherwise it returns FALSE The time per sample is normally ns fastest 1 timebase oversample For an ADC 200 50 20 ns fastest with oversample 1 the timebases are 0 20 ns 1 40 ns 2 80 ns 3 160 ns 18 5 242 880 ns 19 10 485 760 ns For an ADC 212 3 333 ns fastest with oversample 8 0 2 664 ns 1 5 328 ns 2 10 656 ns 15 87 293 952 ns 16 174 587 904 ns Note that this function has no effect when ETS mode is enabled using adc200_set_ets adc200 en r4 Copyright O 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 16 3 2 11 adc200 set time units void adc200 set time units unsigned short units Arguments units The time units which can be one of 1 A200 PS picoseconds 2 A200 NS nanoseconds default 3 A200 Us microseconds 4 A200 Ms milliseconds 5 A200 s Seconds Returns Nothing This function specifies the time units to be used for times returned by adc200 get times and values Copyright O 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 Driver formats amp routines adc200_set_trigger voi
25. he external trigger input and accepts a TTL compatible signal This connector can also be used as a Simple square wave generator This signal generator can be used to compensate x10 scope probes Connector diagram 2 4 3 Ch A ChB 4 M lt gt E x 08 60 0 j D25 Parallel port connector DC 12 volt 500 mA power socket Running LED External trigger Signal generator AUNE Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 Introduction 12 Safety warning We strongly recommend that you read the general safety information below before using your product for the first time If the equipment is not used in the manner specified then the protection provided may be impaired This could result in damage to your computer and injury to yourself or others Maximum input range The ADC 2xx product is designed to measure voltages in the range 20V to 20V Any voltages in excess of 100V may cause permanent damage to the units Mains voltages No Pico products are designed for use with mains voltages To measure mains we recommend the use of a differential isolating probe specifically designed for such measurements Safety grounding The ground of every product is connected directly to the ground of your computer via the provided interconnecting cable This is done in order to minimize interference Always use the provided cable to attach the product to
26. nal digital trigger input The trigger event can be either a rising or a falling edge The ADC 2xx can be programmed to place the trigger event at the beginning of the buffer like an analog scope or at the end of the buffer pre trigger or any point in between The external trigger input is the same as the signal generator output so these two functions cannot be used at the same time Voltage ranges It is possible to set the gain for each channel with the adc200_set_range routine to give an input voltage range from 50 mV to 20 V 10 mV to 20 V for the ADC 212 3 and ADC 216 AC DC operation Test whether the ADC can set the AC DC switch through software using the adc200_has_relays routine Using the adc200_set_dc routine each channel can be set to either AC or DC coupling When AC coupled any DC component of the signal is filtered out For some older versions there is a physical AC DC switch for each channel on the front of the unit for newer versions it is controlled by software Oversampling When the unit is operating at speeds below maximum it is possible to oversample with adc200_set_oversample to take more than one measurement during each time interval This reduces the effects of aliasing and increases the apparent resolution of the ADC Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 7 Product features Scaling The ADC 200 is an 8 bit ADC which returns a valu
27. nformation in the adc200 tar file for more information Functions adc200 get driver version unsigned short adc200 get driver version void If it is possible that your software might be used with other drivers you can use this routine to determine whether the driver is more recent than the one the that you used to develop the software Arguments None Returns 16 bit code that identifies the driver version The upper byte contains the major version and the lower byte contains the minor version Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 11 Driver formats amp routines 3 2 2 3 2 3 adc200_open_unit unsigned short adc200_open_unit unsigned short port This routine opens the ADC 2xx on the specified port The initialization process takes a couple of seconds Arguments port The number of the parallel port that the ADC2xx is connected to 1 for LPT1 2 for LPT2 etc 101 for USB PP1 102 for USB PP2 etc USB ports are named in the order they were connected in Returns TRUE if successful or FALSE if unsuccessful The driver can handle up to three ADC 2xx units at the same time If you wish to use more than one unit call adc200_open_unit once for each unit then call adc200_set_unit to select which unit to use next Note for the Windows version the ADC 2xx does not have access to the actual base addresses for the parallel ports It assumes that they are LPT1 0
28. return from this routine the first entry contains a reading from channel A and the second entry contains a reading from channel B Returns Nothing Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 23 Driver formats amp routines 3 2 22 adc200_get_unit_info short adc200_get_unit_info char str short str lth short line short port This routine writes unit information to a character string There are four lines of unit information available If the unit fails to open only lines 1 and 2 are available to explain why the unit failed to open line Type of information 1 information about the ADC 200 DLL 2 information about the harware version and the connection type status 3 the batch number of the unit 4 the calibration date Arguments str a pointer to the character string buffer in the calling function where the unit information string selected with 1ine will be stored str lth length of character string buffer line selects which line of text to return see table above port the parallel or USB port number to return information for 1 for LPT1 2 for LPT2 etc 101 for USB PP1 102 for USB PP2 etc USB ports are named in the order they were connected Returns The length of the string written to the character string buffer in the calling function adc200 en r4 Copyright O 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide
29. used to set the AC DC switches otherwise it returns FALSE 3 2 6 adc200 set dc unsigned short adc200 set dc unsigned short channel unsigned short dc This routine specifies the position of the AC DC switch Use adc200 has relays to determine if this routine will work with the ADC Arguments channel Use A200 CHANNEL A or A200 CHANNEL B de 1 DC 0 AC Returns TRUE if successful or FALSE if unsuccessful Copyright 1995 2015 Pico Technology Ltd All rights reserved adc200 en r4 13 Driver formats amp routines 3 2 7 adc200_set_range unsigned short adc200_set_range unsigned short channel A200_GAIN gain This routine specifies the input voltage range for a channel If you wish to find out all of the ranges you can call this routine repeatedly and note the returned voltages until it returns zero Arguments channel Use A200_CHANNEL_A 0 or A200_CHANNEL_B 1 gain EITHER a code between O and 10 adc200 h contains defines for these codes OR the required millivolt range Returns voltage range if the parameters are valid otherwise it returns ZERO The following ranges are available gain voltage range 10 mV ADC 212 3 and ADC 216 only 20 mV ADC 212 3 and ADC 216 only 50 mV 100 mv 200 mV 500 mV 1V 2V 5V 10V 0 20V FOOAN OA UBWNF OO adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 14
30. uter using a the 25 way cable provided USB Parallel port operation USB printer port interfaces are not suitable for use with Pico products If you wish to connect a Pico product to a USB port you will need a Pico USB Parallel Port adapter When you install the application software from the Pico CD 1 the computer asks you which port to use select USB PP1 2 once the USB driver software is installed connect the Pico USB parallel port adapter to your PC the computer will automatically configure the drivers Checking the installation 1 Connect DC power by plugging the power adapter into a mains socket and plugging the DC power jack into the socket on the ADC 2xx The red light should now be on showing that the unit is powered The light may switch off when data is not being processed 2 To check that the unit is working start up PicoScope PicoScope should now display the voltage that you have connected If you are using scope probes when you touch the scope probe tip with your finger you should see a small 50 Hz mains signal adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 2 The ADC 2xx has the same connectors as an oscilloscope so you can use standard oscilloscope probes The input impedance is also the same so the x10 function ona scope probe works correctly The BNC connector labelled 4 below E on the unit has two functions in normal use it is t
31. x278 LPT2 0x378 LPT3 0x3BC If your computer does not conform to this standard you should enter the port number corresponding to the actual port base address adc200_set_unit unsigned short adc200_set_unit unsigned short port The driver can handle up to three ADC 2xx units at the same time if you wish to use more than one unit call adc200_open_unit once for each unit then call adc200_set_unit to select which unit to access next Arguments port The number of the parallel port that the ADC 2xx is connected to 1 for LPT1 2 for LPT2 etc 101 for USB PP1 102 for USB PP2 etc USB ports are named in the order they were connected in Returns TRUE if successful or FALSE if unsuccessful adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 12 3 2 4 adc200_close_unit void adc200_close unsigned short port This routine stops the specified ADC 2xx and powers the unit down Arguments port The number of the parallel port that the ADC 2xx is connected to 1 for LPT1 2 for LPT2 etc 101 for USB PP1 102 for USB PP2 etc USB ports are named in the order they were connected in Returns Nothing 3 2 5 adc200 has relays short adc200 has relays void This routine determines whether the ADC 2xx unit has relays to control the AC DC switches Use adc200 set dc to set the relay Arguments None Returns TRUE if the adc200 set dc routine can be
32. your computer As with most oscilloscopes and data loggers you should take care to avoid connecting the ground input of the product to anything which may be at some voltage other than ground If in doubt use a meter to check that there is no significant AC or DC voltage Failure to check may cause damage to the product and computer and could cause injury to yourself or others You should assume that the product does not have a protective safety earth Misconfiguration and or use on voltages outside the maximum input range can be hazardous Repairs The unit contains no user serviceable parts repair or calibration of the unit requires specialized test equipment and must be performed by Pico Technology Limited or their authorized distributors adc200 en r4 Copyright 1995 2015 Pico Technology Ltd All rights reserved ADC 200 Series User s Guide 4 2 Product features 2 1 Specifications Resolution bits Sg A So 6 Input Channels 2 x BNC connectors 1 MQ impedance AC DC coupling External Trigger Ext BNC Input TTL Level Trigger Output Square Wave Signal Generator 50 mV to 20 V in 1 2 5 Steps in 9 Ranges ADC 212 3 and ADC 216 also have 20 mV and 10 mV Ranges ccuracy 96 verload Protection V ampling Rate Samples s 1 Channel 2 Channel mue D O O Signal with ETS uffer Size kSamples cB i enn a E BE E 582 ignal Generator Power Supply 12 V DC nominal at 500 mA max DC 1 3 mm connector cent
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