OS5000 family - OCEAN SERVER
Contents
1. OCEANSERVER COMPASS MANUAL pitch 90 degrees roll 180 degrees Temperature range Accuracy specified for 0 C to 50 C 40 C to 85 C operation decreased accuracy at temp extremes Humidity 20 80 RH non condensing Shock Operating 3 000 G 0 5 ms 10 000 G 0 1ms Data Refresh Rate 0 01 Hz to 40Hz sentence output rate Size 1 x 1 x 0 3 module Weight 2 grams Supply Voltage 3 3V 5VDC Will operate with up to 15VDC using 3x the power Power consumption 30 ma 3 3V S variant 35 ma 35V US variant in USB mode Serial Data Interface RS 232C levels TTL and USB 2 0 based on Variant 4800 115000 baud 8 bit 1 stop no parity 19200 default Sentence Format NMEA0183 Style four sentence formats supporting xor parity SHCHDT OHPR C comma delimited Supports Acceleration amp Magnetic sensor output in X Y Z Magnetic Routines Compensation Hard Iron and Soft Iron calibrations supported note Soft iron V1 4 or later firmware OCEANSERVER COMPASS MANUAL Electrical Connector and pin assignment Top Side View I sont m Pin 1 Pin2 White Black Table Below provides full detail of all pins OS5000 S OS5000 USD TOP Side 1 Serial Connector 7 pin Molex 1 25mm connector Molex 51021 0700 Available on www Mouser com along with pins and tool to make custom cables Description Pin Color Signal Serial C2. Hard iron Un magnetized ferrous materials in the area of the compass cause Soft iron effects Magnetized ferrous materials near the compass cause Hard Iron effects Hard Iron can be cancelled out by going through the rotational calibration described below Softiron effects should be addressed during the design in phase and compasses should be located away from such items to minimize impact to the sensor OceanServer compasses with firmware version V1 4 and later include a soft iron calibration option The soft iron correction routines work very well if the soft iron effects are minimized If you look at the measured data regarding distortion at a distance as seen in the earlier table you will see that the placement of soft iron at a small distance from the compass can make huge differences As mentioned above finding the right spot to mount the compass where the effects of local magnetic sources are minimized is key Remember any ferrous material Nickel Iron Cobalt Steel Some Aluminum alloys etc will become magnetized and this magnetization can change by moving it through a magnetic field present on the earth s surface Distance from the sensor is critical to the compass s ability to keep an accurate heading after a calibration You can use the OS5000 as a magnetometer to locate large static fields in your target system Turn on Magnetic Vector and scalar and move the compass around in your system to s
3. 4 62 1 63 s 2 55 lash Write C348 9PB8 3R 8 1T18 4 01 C348 9PB8 3R 8 1T18 4 01 C324 4P8 2R 8 3T18 4 405 C291 7P8 2R 8 5T18 4 4 F After you run through the calibration process you will see the correction values generated by the process At this point the soft iron calibration is completed You should go back and check the cardinal points with your system You should see your system more in line with the cardinal points If the compass is still not reporting accurate information compared to the known good reference compass you should run through the calibration process again and carefully 30 check each step In some cases the magnetic field may be too disturbed for accurate calibration and distance from soft iron is the best solution Compass Settings Relating to Filtering Measurements Not Required for Most Applications Since the OS5000 family of digital compasses use a fast 3 axis accelerometer to sense the gravity 1G static vector to determine its Roll and Pitch angle you may need to filter out other dynamic acceleration introduced by your platform These accelerations will decrease the accuracy of the Roll and Pitch estimation using Euler angles Introducing filtering will improve the accuracy if the platform acceleration is dynamic and can be filtered out 1 Analog to Digital Converter Decimation Filter The analog to digital converter is an AD7799 24 bit Sigma delta converter It has an internal decimation filter
4. ASCII 27 decimal noted as lt esc gt in this manual Command with a value lt esc gt Kvalue lt space gt Action command lt esc gt K Where type 1 is the format for a command that has a value supplied Note all values are decimal integers examples 10000 1000 2345 If the value needs a floating point number multiplied by 10 Example lt esc gt Q123 lt space gt is a value of 12 3 for heading The second type Type2 is commands that immediately have some action One example is the calibrate command lt esc gt C Note1 Entering Commands Push the escape lt Esc gt key prior to a key command The command keys are CASE sensitive so if it asks for a R lower case r will not work Note2 Some command changes require the compass to be power cycled for changes to take effect Example BAUD RATE CHANGE 15 OCEANSERVER COMPASS MANUAL Key Command Description of the command Esc B BAUD RATE Set new baud rate 0 6 change takes effect after power cycle 0 4800 1 9600 2 14400 3 192000 4 38400 5 57600 6 115200 lt Esc gt R SENTENCE OUTPUT RATE Set the compass output rate 50 to 40 Rate is in samples per second and negative are seconds per sample ie 20 20 samples second 10 10 seconds per sample A rate of 0 will stop output At higher output rates the baud rate will need to be increase beyond the standard setting Esc X OUTPUT DATA FIELD SELECTION Fields t
5. Firmware version 1 5 introduces 5 additional mounting positions for users that need the compass orientated 22 differently in their product Note The OS5000 USD compass only supports orientation 1 N Orientation 1 Standard flat Factory Default To change to another Orientation you will need to hit the Escape key and enter command Key E Below is the output factory default is 1 Standard flat CMD E see manual you MUST recalibrate compass after changing 1 Standard flat 2 front 3 port 4 roof 5 back 6 starboard Mounting Oriention 1 6 1 Value and Enter or Esc CMD E Below are figures for orientation Options 2 6 Once you have changed the orientation you will need to recalibrate the compass starting with the XY calibration then move on to the Z from the new orientation position Note Roll and Pitch should both indicate zero values in the new orientation position prior to starting the XY calibration and then roll the compass 90 degrees for the Z calibration B Option 2 front above 23 Option 3 Port above d Option 4 Roof above Option 5 Back above d Option 6 Starboard 24 Calibrating the Compass The OceanServer compass products each require calibration in the user s device for accurate operation The factory calibration is done to test the compasses in the factory and have the hard iron offsets of our steel building and won t provide accurate headings until c
6. My Y component Mz Z component Acceleration Raw Output Data The acceleration raw data in G s can be output The format is as follows G1 001 Gx0 621 Gy0 212 Gz0 754 G Gravity vector will be close to 1 if no dynamic acceleration present Gx X axis component of acceleration in G s Gy Y axis component of acceleration in G s Gz Z axis component of acceleration in G s 32 The G vector overall length will tell you if the platform is stable or experiencing dynamic acceleration Any dynamic acceleration changes the vector length from neat 1 to a lower or higher value Configuring the output sentence of the compass Not Required The lt esc gt X decimal lt enter gt command will let you set the bit mask of what values the compass outputs If you enter the max value of 4095 all 12 bits set the compass will output all values Use the Compass Demo program to help your set this field on the compass The program can be downloaded from WWW Ocean setvet com compass Installing Windows Demo Utility The windows demo utility is located on the web Download the CompassUtilityV26installer zip file and open it This installer will put the compass demo program on your system WWNW Ocean setvet com compass Index of compass Name Last modified Size Description Parent Directory 05 Nov 2010 12 27 CableSpecs zip 05 Mar 2008 12 06 129k Comdiq32 zip 16 Jul 2009 09 05 58k CompassCsourceExampl 08 Sep 2008 09 03 83k CompassUtilityV
7. cc S Life Count Pst Deguass every bp sentences S Zero Depth at surface P Range 180 0 180 0 emn Average Samples 5 Set 4 Declination Set Q Terminal Window v Show Compass Output AD Decimation Filter b 9 1R43 56Mx 80 45My 160 86M271 53A0 998 2F 1R43 57Mx 80 46My 160 86M271 55A0 998 2B 1R43 58Mx 80 45My 160 86M271 56A0 999 25 1R43 58Mx 80 45My 160 86M271 57A0 998 26 1R43 58Mx 80 46My 160 85M271 60A0 999 21 USB Drivers for the OceanServer OS5000 USD family of compasses You must download the USB drivers for windows directly from our web site These are only required if you re using the USB interconnect option on the OS5000 USD compass Remember if you have an OS5000 USD it suppotts either RS 232 serial or USB by selecting the correct cable There are two connectors on the module The serial connector is on the TOP side and is 7 pin the USB cable is 6 pins and on the bottom side of the module The standard USB dirvers can be downloaded from http www ftdichip com Products ICs FT230X html 35 Our demo program runs on Windows only but on all other operating systems you can open a terminal program to the virtual serial port and talk listen to the compass with its NMEA string WINDOWS ISSUES SERIAL MOUSE PROBLEM There is general problem with all windows systems and devices that send unsolicited serial input on a COM port Windows will often think the device is a serial mouse and connect the driver Th
8. IndexOf 1 GetChecksum sentence Calculates the checksum for a sentence public string GetChecksum string sentence Loop through all chars to get a checksum int Checksum 0 foreach char Character in sentence if Character S Ignore the dollar sign else if Character Stop processing before the asterisk break else Is this the first value for the checksum if Checksum 0 Yes Set the checksum to the value Checksum Convert ToByte Character else No XOR the checksum with this character s value Checksum Checksum i Convert ToByte Character Return the checksum formatted as a two character hexadecimal return Checksum ToString X2 40 Customer Support For the quickest technical support send e mails to support a ocean setver com OceanServer Technology Inc 151 Martine St Fall River MA 02723 USA Copyright 2007 2015 by OceanServer Technology Inc All Rights Reserved 41
9. degrees at least one complete rotation This step should take 20 plus seconds when you just get you have found the Z max and Z min values Terminate the sequence by hitting the SPACE bar Important Note The Z command should be done in the same location to calibrate and align the Z axis sensor to the X Y This is important for tilt compensation Errors in heading when the device is tilted will result from no Z axis calibration Note If the platform is not level during the calibration procedure just abort it and re run it Le Hit space and start at step 3 above Compasses can also be calibrated in the latest version of the OceanServer Windows Demo program The basic steps are the same as described above The feature can be found under the program button Optional Soft Iron Calibration The above mentioned C Z calibration routines do not compensate for soft iron effects Soft iron batteries wires with moving currents and other high permeability materials in the near field cause these These are generally far weaker than hard iron effects Choosing a good compass mounting location with distance from soft iron structures should be attempted In cases where the sensor will be impacted by soft 29 iron you should run the soft iron calibration available starting with firmware version 1 4 The soft iron compensation routine is started by hitting the lt Esc gt key command You want to select option 2 and foll
10. firmware version 1 5 Additional Note the OS5000 USD version supports pressure measurement for depth Pictures may not reflect latest release OS Compass Design Features Hardware Variants OS5000 S RS232 Only OS5000 USD RS232 amp USB note OS5000 USD Standard Features includes Depth Option Magnetic Sensors OCEANSERVER COMPASS MANUAL Honeywell two axis AMR sensor for X Y plane sensing Honeywell z axis AMR sensor Accelerometer tilt sensor Three axis accelerometer Microprocessor 50 MIPS processor that supports IEEE floating point operations for accurate tilt compensation AD Conversion 24 bit Sigma Delta converters with differential inputs All Models are ROHS Compliant Additional Note The OS5000 family of compasses is the next generation of compasses offered by OceanServer Technology The table below gives a cross reference to previous generation parts Previous Generation Part Replacement Part Comments OS1000 OS5000 S Direct Replacement One patt replaces all units depth MEC c EE OS5000 USD USDK connected via Setial port connector OS3000 OS5000 USD Smaller 1 x1 form factor Specifications Parameter Value Azimuth accuracy 0 5 deg RMS Heading while level undisturbed field 0 1 deg resolution Inclination pitch and roll Typical 1 accuracy lt 30 tilt accuracy Inclination range 80 degrees output for full rotation at decreased accuracy
11. is mounted 2 inches from a paddle wheel the compass will see up to 90 degrees of offset in heading due to the magnets moving Since the magnetic field falls off as the inverse square of the distance moving the compass a small distance can make large improvements in the accuracy Mounting Distance inches Error heading degrees 2 90 degrees 5 10 degrees 9 1 6 degrees 11 0 2 degrees So moving the compass 10 inches from these moving magnets we were able to remove all of the significant error introduced in your reading 21 C288 6P 0 2R 0 1T26 6 20 C288 4P 0 2R 0 2T26 6 21 C288 6P 0 2R 0 2T26 6 23 AAAA Notice Level in roll and pitch CMD C Bridge offset Calibrate X Y lt space gt when done XyxXyXyXY XyXyX XXYxYY xYxYxYxYxYxYxYxY xYxYxYxYx YxYxY xYxYxYxYxYxYxYx YYxYxYxYxYxYY YYYYYYYY YY Y YY Y YYYy Yy Flash Write C346 7P1 5R 0 1T26 9 06 C0226 ID N IR AN YTO amp O 10 OS5000 Mounting hole locations stand offs shipped with compasses Visit OceanServer s download page for 3D Models and Mechanical Drawings www ocean server com download html 4X 116 V THRU gt N New Mounting Positioning with Firmware Version 1 5 and Later On firmware version 1 4 and earlier always mount the compass with 7 pin side 1 up this 1s the factoty default mounting position for all firmware versions Side 1 on all compass models has the white arrow imprinted on the red etch
12. 00Mz0 000Ax000 0Ay000 0Az000 0 cc C212 4P2 5R 14 0T28 4Mx107977 90My 79422 00Mz173 27 Ax0 045Ay 0 245Az0 977 3A This sentence format provides a text tag in front of each data type so the user program can parse them accurately regardless of which data elements are activated In effect evety data element has leads with its unique name Possible fields reported in the sentence use the lt esc gt Xnnnnn lt space gt command to configure the desired fields for output Hhh h Heading in degrees corrected for Declination if one is entered Ppp p Pitch angle P precedes the pitch angle in degrees Rrr rr Roll angle R precedes the roll angle in degrees Tttt Temperature of the compass board crude measure taken from the core microprocessors internal sensor Used for relative measurements of environments not accurate We provide a single point calibration offset using the lt esc gt command Standard Factory Format for OS5000 S or OS5000 USD The standard setting below is lt esc gt 1 lt space gt command Example C320 5P0 2R 18 3T19 0 3C Mx My Mz Magnetic field strength reported on each sensor The units are calibrated to milliguass by the user setting the local horizontal field strength before a full calibration Ax Ay Az Acceleration measured on all three sensors The units are in G for each sensor You can also output the vector length acceleration scalar which will be close to 1G cc This is the end of line ch
13. 26ins 05 Nov 2010 12 23 5 3M B0 Oc I II IIt OS4000DesiqnFiles zi 13 Jul 2010 09 16 71k OSframework1013 zi 26 Mar 2010 12 54 1 5M USBdrivers 12 Apr 2010 10 07 archivefiles 05 Nov 2010 10 49 teraterm 4 64 exe 05 Jan 2010 09 56 6 5M 33 Main Screen OceanServer Digital Compass Demo Utility 2 1 x Configure Open Port Close Port OceanServer TECHNOLOGY INC e Heading 319 9 Pitch 0 1 Roll 43 4 Configuration Screen Setup for Digital Compass Serial Com Graphic Charts Input Port X r Magnetic Chart r Port Config Min g j Baud Rate 13200 Max Parity None z r Acceleration Chart 4 Data Bits e Min Stop Bits h Max 1 34 Program Screen allows for calibration custom screen displays and other settings 42 OceanServer Digital Compass Demo Utility 2 1 xi Configure Open Port Close Port Output TECH N lt INC Calibration X Y Compass Level g Baud Rate s6o0 7 B Calibrate Z Compass 90 Degrees z Output Rate samples s Set R b F 50 40 Show V Azimuth Depth Acc Vect Ensa Restore FACTORY Defaults F Iv Pitch lv Mag S Gyros VV Roll v M Vect Gyro Vect B Max Pressure 100 PSI Set M IV Temp WM
14. 978 28 utput Sentences 127 gt 2 alue andi Enters or Esc 4 lash Wri HCHDT 212 4 T 2C HCHDT 212 4 T 2C HCHDT 212 4 Tx2C MD sc utput Sentences 127 gt 4 alue and Enter or Esc 8 lash Write 12 4 2 5 14 0 28 6 107934 59 79258 69 173 27 0 045 0 244 0 978 12 4 2 5 14 0 28 5 107940 70 79263 87 173 25 0 045 0 244 0 978 12 4 2 5 14 0 28 6 187929 16 79273 99 173 26 0 845 0 245 0 977 12 4 2 5 14 0 28 7 107929 85 79259 35 173 25 0 045 0 245 0 97 12 4 2 5 14 0 28 7 107939 34 79243 55 173 27 0 045 0 245 0 977 12 4 2 5 14 0 28 7 107954 94 79237 44 173 27 0 045 8 245 0 977 a2 P uds 5 14 0 28 7 107937 20 79229 34 173 29 0 045 0 245 0 977 ui C 22 Jan 2888 OS588B8 V1 4 space Figure Compass output for each of the four supported output formats The command lt esc gt lets you select the bit mask for the desired sentence format The compass is programmed with an output rate and it sends sentences at this fixed rate The rate is programmed with the lt esc gt R command Values lower than 1 per second use a negative number 100 is 0 01hz 10 is 0 1 hz 2 is O 5hz Values greater than 0 are in sentences per second HZ A value of 10 is 10hz 40 is 40hz and so on If 11 OCEANSERVER COMPASS MANUAL you program a tate of 0 the compass will cease output but still respond to lt esc gt commands Format Type 0x01 1 10 C format Chhh hPpp pRrr rTtt tMx0 000My0 0
15. OCEANSERVER COMPASS MANUAL Ocean Yerver T EOHNOLUOZS TY ING Digital Compass Users Guide OS5000 Series P N 90 05000 00 REVISION 5 0 O 2007 2015 OceanServer Technology Inc 151 Martine St Fall River MA 02723 USA WWNW OceCan setver com Sales Q ocean setvet com or suppott a ocean server com OCEANSERVER COMPASS MANUAL Table of Contents Introduction to the Tiny Compass Family c eeeeeeeeeeeeeeeeeeaeeeeeeeeeeeeeeeeeees 3 OS Compass Design Features niae Eee e out to EDa eta beri odupateU Pu cesa UbYE 4 lee eue CLE 5 Electrical Connector and pin assignment sse 7 CAD M e 9 Firmware Updates for the OS5000 Compass Family 10 Communicating with the compass RS 232 or USB ssssussss 11 Output Sentence FORMALS ciao deu Setup dde o Le eL Deo du oga seine duae EC BIC 11 Format Type 0x01 1 10 GC format sssssssssseeeenenernennes 12 Format Type 0x02 2 10 5OHPR Sentence sese 13 Format Type 0x04 4 10 HCHDT Sentence sese 13 Format Type 0x08 8 10 comma delimited Sentence 13 Format Type 0x10 16 10 Direct LCD Oultput sseeeeeeseeeeeee 13 Output Parameter Selection Table ccccccsessseecccessseeeeeseeeeseeeeeeseesseeeeesnees 14 Terminal Emulation Programs for Communicating wi
16. alibrated in the user s device The roll and pitch angles are factory calibrated and will be accurate as shipped from the factory Calibration step 1 Mount the compass in your device or system make sure it is reporting level ROLL and PITCH when you device is level 2 Take you device outdoors away from any ferrous material on a level wooden table or other non ferrous surface You will need to use a handheld compass to find magnetic North and be able to spin your device with compass mounted and align it to the Cardinal points N S E W Actually North and the right angles give the other headings 3 Do the escC escZ hard iron calibration do the 2D soft iron calibration esc 2 lt enter gt 4 Test your platform heading after calibration aiming it N E S W for accuracy Note These steps are described in more detail in this chapter Mounting Location is Critical The selection of a mounting location is critical to accuracy of any magnetic compass In a later example we show the compass mounted in our AUV underwater robot picture page 27 Our practical experience taught us that if we mount the compass near the battery packs it will drift calibration 10 Degrees quickly after calibration The root cause of this problem is that the battery packs are all mounted in steel cases each cell and turn out to be bar magnets with field strengths 3x the earth s field we are trying to measure After calibration we will remove this effect
17. aracter the cc is the HEX X OR sum of the characters between the and the This is the NMEA standard format OS5000 USD Example C328 3P28 4R 12 4T21 1D21 01 lt checksum gt cr 1t e Compass heading 328 3 degrees e Pitch angle 28 4 degrees 12 OCEANSERVER COMPASS MANUAL e Roll angle 12 4 degrees e Temp 21 1 degrees e Depth 21 01 feet This is only output on the OS5000 USD Format Type 0x02 2 10 SOHPR Sentence OHPR valuet1 value2 value3 value4 cc The OHPR sentence is activated with the lt esc gt 2 lt space gt command It provides a comma delimited list of all of the parameters selected for output with the lt esc gt X command Format Type 0x04 4 10 SHCHDT Sentence HCHDT 212 4 T 2C The NMEA0183 standard true heading sentence is supported for output The HCHDT sentence is activated with the lt esc gt 4 lt space gt command To have the heading be true the user must program the compass with the local declination value using the lt esc gt Qnnnn lt space gt where nnnn is the degress times 10 for local heading offset Example lt esc gt Q125 lt enter gt will offset the heading 12 5 degrees for every value reported Format Type 0x08 8 10 comma delimited Sentence value value2 value3 va This sentence outputs the data as a simple comma delimited list of the requested values This sentence is activated by the lt esc gt 8 lt space gt command and it outputs all data
18. but if it shifts a small amount it will impart a large error on the calibration and the accuracy Real World Example We now mount our compass 1 foot forward of that point in the nose cone of the vehicle AUV We just did a test calibrating the AUV in Boston MA Flew the AUV s to the Caribbean and ran 1500 Meter long underwater tests navigating using the compass heading comparing error when we surfaced and acquired a GPS fix In all tests our heading error was less than 1 degree The effects of the magnetic field of the battery fall off as the inverse of the distance So moving it from 1 inch to 4 inches away the field strength falls off by 1 16 or 6 of the original disruptive field A HUGE improvement 25 In a white paper a compass vendor shows they can mount the compass next to a battery and calibrate out the effects They neglect to mention that the field will shift significantly if the magnetization of the battery changes ever so slightly Things get magnetized by moving through a field like shipping on UPS or Fedex Background Compasses operate by measuring the earth s magnetic field and locating magnetic north When mounted in real platforms or devices there are other local magnetic fields or materials that disrupt or offset the earth s magnetic field Sources to be aware of are ferrous metal electric currents and permanent magnets in electric motors There are two sources of magnetic field distortion Soft iron and
19. curacy lt 30 tilt Pitch Angles 90 degrees Roll Angles 180 degrees Tilt compensated electronically gimbaled Tiny size 1 x1 x0 5 less than 2 grams weight Low Power Consumption lt 30ma 3 3V Hard and soft iron compensation routines Optional support for a high resolution Depth or Altitude sensor 24 bit AD Serial Interface o RS232 or USB or TTL see OS4000 T o Baud rate programmable 4 800 to 115 000 baud Rugged design o 10 000 G shock survival o 40 C to 80 C operating temperature Accuracy specified for 0 C to 50 C ASCII sentence output in several formats NMEA checksum High Data Update Rate to 40HZ Support for True or Magnetic North Output Precision components o 3 Axis magnetic sensors from Honeywell o 3 Axis Accelerometers from ST Microelectronics o 24 bit differential Analog to Digital converters from Analog Devices OCEANSERVER COMPASS MANUAL o 50 MIPS processor supporting IEEE floating point math OS5000 S Signals RS 232 Levels 3 Axis Compass 1 x 1 size with full RS 232 support single connector on the topside note arrow imprinted on this side of the module OS5000 USD Signals USB or RS 232 3 Axis tilt compensated compass 1 x 1 Has both Serial amp USB direct interface and has connectots on both sides of the module TIT mn Serial 7 Pin 6 Pin USB Cr 3 Always mount compass with 7 pin side 1 up even when using USB connector other mounting positions available with
20. d in the firmware Mount the compass in a mechanically stable location so this it moves with the vehicle or device but doesn t vibrate Lots of vibration will cause the compass to be less accurate Metals such as aluminum brass or copper do not block magnetic fields but currents can still flow through them that could create unwanted local magnetic fields Metals such as iron and steel will distort the magnetic field 20 OceanServer ships compasses with plastic standoff but users should insure that the compass has sufficient distance from ferrous objects that could bend the earth s magnetic field and disrupt compass accuracy Aircraft Note Most all electronic compasses use the 1G gravity vector to estimate tilt angles including OceanServer compasses The tilt angles are determined by measuring the earth s static gravitational vector Since dynamic and static acceleration are indistinguishable when used in aircrafts with high acceleration and banking turns the dynamic acceleration will introduce an error in both roll and pitch angle reported by the compass as well as heading errors Only level headings will be accurate when aboard a plane and vibration needs to be considered Strong vibration also applies acceleration to the compass and can cause errors if the amplitude of the acceleration is significant as compared to the earth s 1G acceleration due to gravity Mounting Location Example In one real world example if the compass
21. e screen cursor will jump around and the compass COM port will be busy Fix this problem by opening CONTROL PANEL gt SYSTEM gt HARDWARE gt DEVICE MANAGER plug in the compass see the serial mouse appear Unplug the compass so you can use the mouse and right click and disable this Serial mouse Basic Commands to Configure the OS5000 1 Mount the compass in the best location away from ferrous materials 2 Configure the compass firmware hit lt Esc gt key prior to any command key a Talk to the compass using a terminal program such as Tera term Settings 19200 8 1 N to the device 9600 with firmware v1 0 b lt esc gt V Check firmware version c lt esc gt B Set compass baud rate Active after power cycle d lt esc gt C calibrate X Y rotate 360 in 15 seconds level X Y e lt esc gt Z Calibrate X tip platform on side rotate 360 f lt esc gt Q Set the Declination value if you want True magnetic output This will offset for the delta between magnetic north and true north g lt esc gt R set the output rate for your application h lt esc gt set user sentence format 1 2 4 8 i lt esc gt soft iron calibration align system to N S E W magnetic j lt esc gt A Set averaging to smooth the readings Note These ate the most common commands used configurations will vaty 36 Depth or other sensor Connection for OS5000 USD OS5000 USD connection
22. ee where the fields are the strongest This is a great way to find a quiet area away from the strongest field lines In the case of our AUV it showed that the battery packs look like a 3 foot long bar magnet 26 Magnetic Field Examples Ferrous Material in Tail Non Fetrous Bow Plus an Electric Motor Least Magnetic Creating Magnetic Field Disturbance Field Disturbance Best Place for Not an Ideal Place for Compass Compass Placement Placement bas EILE c Users will need to calibrate the compass Step 1 Select appropriate location and install OceanServer Compass in device IMPORTANT NOTE Compasses require users to hit the lt Esc gt key prior to each programming calibration step This has been added to prevent accidental programming Step 2 Open a Hyperterm window to take two separate measurements X Y together followed by Z for calibration The Virtual terminal settings for the compass serial port 19200 baud 1 stop no parity We recommend TeraTERM free software A Nema 27 string of data will begin outputting when connected properly ie C328 3P28 4R 12 4T21 1D21 01 Step 3 Calibrating X Y a Check that the platform is level observe Pitch P0 x and Roll RO x data and confirm they are less than 1 degree Next fully rotate the platform to make sure it will remain level during the calibration process The area should be clear of soft and hard iron objects that could disrupt the earths magnetic f
23. elements selected in the lt esc gt Xmask lt space gt command This sentence format is only available with firmware version 1 4 or later Format Type 0x10 16 10 Direct LCD Output Azimuth 0 0 Elevation 0 0 In this mode the compass directly sends the data and formatting commands required for a Crystalfontz 2x16 LCD display This can be used in applications for antenna aiming In this mode the compass is temporarily mounted to the antenna in the field and a cable then goes to a small handheld box with and LCD and a 9V battery This is all that s needed create a very accurate antenna positing system The compass is calibrated for a particular antenna frame to remove it s soft are hard iron effects and the compass will provide excellent results for quickly and accurately aiming antennas 13 OCEANSERVER COMPASS MANUAL This sentence is activated by the lt esc gt 16 lt space gt command You should also change the output rate to 2 lt esc gt r set to 2 This sentence format is only available with firmware version 1 5 or later Output Parameter Selection Table Note not all compasses support all features Order Bit value base 10 Parameter Name 1 1 Azimuth 2 2 Pitch Angle 3 4 Roll Angle 4 8 Temperature 5 16 Depth feet 6 32 Magnetic Vector Length 7 64 3 axis Magnetic Field readings x y z 8 128 Acceleration Vector Length 9 256 3 axis Acceleration Readings x y z 10 512 rese
24. ield cars motors wires with current magnets etc Rotate 360 Degrees Parallel to the Earth Compass looking into Back connector B X Y Calibration b Calibrating X Y Enter lt Esc gt key next enter uppercase C key and slowly rotate the device at least one complete rotation for at least 20 plus seconds Note the device should be kept as level as possible to calibrate the X Y magnetic sensing elements Terminate sequence with SPACE bar key after you have slowly rotated the device and observed the following output this indicates you have found the X Y max and X Y min values c Final X Y Note If the platform is not level during the calibration procedure just abort by hitting the SPACE bar and re run it i e Hit space and start at step a above 28 Step 4 Z Calibration Rotate device 90 degrees so it is turned on its side back connector Rotate 90 degrees Next rotate 360 degrees Compass looking into while at 90 degree angle ecc a Z Calibration Roll the platform 90 degrees The atea should be clear of soft and hard iron objects that could disrupt the earth s magnetic field cars motors wires with current magnets etc You want the calibration to be done in the same place as the C calibration as it needs to see the same earth s magnetic field Enter Z Calibration mode Push lt esc gt Z on the keyboard Slowly rotate the device 360
25. loaded in trial from Microsoft com NMEA CHECKSUM GENERATION 1 Example of checksum calculations in VisualBasic 38 Returns True if a sentence s checksum matches the calculated checksum Public Function IsValid ByVal sentence As String As Boolean Compare the characters after the asterisk to the calculation Return sentence Substring sentence IndexOf 1 GetChecksum sentence End Function Calculates the checksum for a sentence Public Function GetChecksum ByVal sentence As String As String Loop through all chars to get a checksum Dim Character As Char Dim Checksum As Integer For Bach Character In sentence Select Case Character Case S c Ignore the dollar sign Case c Stop processing before the asterisk Exit For Case Else Is this the first value for the checksum If Checksum 0 Then Yes Set the checksum to the value Checksum Convert ToByte Character Else No XOR the checksum with this character s value Checksum Checksum Xor Convert ToByte Character End If End Select Next Return the checksum formatted as a two character hexadecimal Return Checksum ToString X2 End Function 2 Example of checksum calculations in C Returns True if a sentence s checksum matches the 39 calculated checksum public bool IsValid string sentence Compare the characters after the asterisk to the calculation return sentence Substring sentence
26. o Display bit mask of 5 bits entered in decimal 31 all active Sum up the values Azimuth 1 Pitch 2 Roll 4 Temp 8 depth 106 lt Esc gt Q DECLINATION ANGLE INPUT FOR TRUE NORTH This allows the user to specify a fixed heading offset to be applied to all heading output data In most cases this is used to adjust for local compass deviation in your area This information can be found on the web using the World Magnetic Model and you local LATITUDE LONGITUDE Enter Declination angle to create offset for compass Azimuth Value is 10x degrees Example 103 10 3 degrees 152 15 2 degrees lt Esc gt C CALIBRATE HARD IRON X Y SENSORS LEVEL PLANE Calibrate the compass in the platform Level the platform and prepare to rotate it very slowly When the output reports XxYy it is finding new calibration data keep rotation until you see only output You MUST keep the platform level while you rotate Validate the Roll and Pitch angles are lt 1 degree in the output string RO x PO x before starting lt Esc gt 7 CALIBRATE HARD IRON Z SENSOR ROLLED 90 Deg Rotate your platform 90 degrees on its side This will place the Z axis in the same earths magnetic field the C calibration saw for the xy sensors Perform once complete and slow rotation 16 OCEANSERVER COMPASS MANUAL lt Esc gt H ot oth HELP MENU Help Menu lt Esc gt A FILTER HEADING ROLL AND PITCH non g
27. onnector on all Compasses 1 White P in Pressure Input from Transducer OS5000 USD only 2 Black GND Ground 3 Red Vin DC Power Input DC voltage Unreg in the range of 3 3V 5V 4 Orange NC RESERVED Do Not Connect OCEANSERVER COMPASS MANUAL 5 Black GND Ground Use with RS232 6 Green Tx RS 232 Transmit DB9 F pin 2 7 Blue Rx RS 232 Receive DB9 F Pin 3 Note Users that only require TX signal The OS5000 compass uses low power RS 232 transceivers these will go to sleep if the compass is not connected to a valid input level and there will be NO compass output If you would like to connect the compass in TX only mode i e no input RS 232 signal you should make the following connection in the cable Compass RX Blue wire pin 7 should be connected to the Power Input Red wire pin 3 This will keep compass TX green wire Pin 6 transmitting on it regular schedule OS5000 USD Bottom side 2 6 pin single row header Molex 1 25mm connector Molex 53261 0671 Available on www Mouser com along with pins and tools to make custom cables Pin Color Signal Description 1 Green USB D 2 White USB D 3 Red 5V Regulated USB Power OCEANSERVER COMPASS MANUAL 4 Black Ground USB Power 5 Reserved Must be no connect 6 Reserved Must be no connect Cables OceanServer offers a varie
28. ons where flat mounting is not possible These are shown graphically in a later section of this manual Mounting options 1 6 E 1 Default flat This transformation is not possible on the OS5000 USDK compass lt Esc gt a ACCLEROMETER MAXIMUM RANGE Change Accelerometer maximum measurement range Options are 0 1 default is 0 2G output 1 6G Important Note 6G output results in less roll and pitch resolution The 6G range should only be used if the user is trying to measure the effects of X Y Z acceleration more than the angle of the compass The lt esc gt X command lets the user select acceleration vector and scalar data output lt Esc gt amp DUMP CONFIGURATION PARAMETERS Dump all compass settings in a form that can be parsed or saved and sent back to the factory when configuration questions arise FW_Version V1 5 FW_Date 1 Jul 08 Serial number 000765431 Test date 01 Jan 08 18 Output_Format 1 Display_Fields 15 HW_Mounting_Pos 1 Baud_Rate 5 Set Reset_Rate 8 Output_Rate 40 Averaging 0 lt Esc gt SOFT IRON COMPENSATION Soft Iron Compensation The values are O disable 1 enable 2 generate calibration When you enter generate 2 you need to have the system with the compass in installed and freshly calibrated via the lt esc gt C lt esc gt Z commands You will need to align the system to cardinal points according to a magnetic compass N S E W in an area free of magnetic di
29. ow the screen prompts see example screen shot below Important setup steps prior to running soft iron calibration Before starting the calibration you need to have the system with the compass installed and freshly calibrated via the lt esc gt C lt esc gt Z commands You must have declination set to 0 before soft iron calibration begins check setting by esc Q and make change to 0 if necessary then hit lt enter gt You will need to align the system to the four cardinal points according to an accurate reference magnetic compass 0 North 90 East 180 South 270 West in an area free of magnetic disturbance Once you have your device or system properly aligned starting at 0 North you want to start the soft iron correction with the lt esc gt command followed by entering 2 Actual calibration routine shown below B COM4 Tera Term VT File Edit Setup Control Window Help C356 8P6 5R6 6T18 4 23 C356 8P6 5R6 6T18 4 23 C358 8PB 5R8 0T18 4x23 C358 8PB 5R8 0T18 5 22 C358 8PB 5R8 0T18 4x23 C358 8PB 5R8 0T18 4 23 C358 8PB 5R8 0T18 4x23 C358 8PB 5R8 80T18 4x23 C358 8PB 5R8 0T18 5 22 oft Iron 8 Off 1 On 2 Calibrate gt 2 gt 6 alue and Enter or Esc lign platform Suactiy North degrees then hit lt Space Bar I lign exactly East 98 degrees then hit Space Bar gt lign exactly South 188 degrees then hit Space Bar gt lign exactly West 2780 degrees then hit Space Bar gt 15 96
30. rved 11 1024 2 axis Gryo Output X y discontinued Part 12 2048 Reserved 13 4096 Reserved Table The output order and bit values for each of the possible output fields is shown in the above table The lt esc gt X The lt esc gt Xmask lt space gt command uses a decimal mask If you want heading roll and pitch active add the Bit Values up for the fields Le 1 2 4 7 now use the 14 OCEANSERVER COMPASS MANUAL command lt esc gt X7 lt space gt to enable these three fields Remember the mask is decimal so just add the bit field values up from the table Terminal Emulation Programs for Communicating with the Compass Hyperterm Issues OceanServer compasses will usually show up as an additional Hyperterm port when properly connected to a system If the compass cannot be communicated programmed check to confirm the Hyperterm port has the correct settings baud is 9600 8 1 N older compasses or 19200 with firmware v1 1 or later If the settings are correct it could be a Hyperterm system issue and you may want to download a different terminal program One possible program is Tera Term A windows version of Tera Term installer is located at http www ocean server com compass teraterm 4 62 exe Compass Command Summary Table The compass is configured and calibrated using a set of commands sent to it via its setial port connection The general format of all commands to the compass are sending it the ESCAPE command key
31. s at 0 5V is so if you forgot to plug in the sensor the OS5000 USD will report a large negative number as an error case 37 Note The pressure analog signal white wire is single ended and can pick up noise in your system Try to keep the pressure sensor near the compass and or use shielded or twisted pair wires The best way to run this is to operate the compass from 5V and run the 5V GND white wire from the compass to the pressure transducer so no local ground noise is introduced PROGRAMMING NOTES OceanServer offers developers a Source Code Example Program that communicates with the OS5000 compass under Windows This program can be downloaded from OceanServer download page http www ocean server com download html Fle Edit View Projet Build Debug Data Tools Window Community Help i oF Gd ak ua mis Sin ibh in a GE S ee Compass Demo Z Properties coon 9e ee 3 4 References E cm undo ME i i E fect S g Lio Court s a Send H Cf frmMain cs Vect v SPIEn 20 4f Program cs Send Gyro qSolution Explorer jy Data Sources FERRER 00Gx 0 01Gy0 00L612124S0 28 Poitnmediate Window 23 Error List Ready The source code program configures and operates a serial port reads the compass configuration allows for sending commands and configuring the compass The program is written in Microsoft Visual Studio C This compiler can be down
32. s per second The range is 1 1 sample per second to 40 40 samples per second 40 hz lt esc gt R n lt enter gt change the output rate of the compass to n If your using output rates of greater than 20 hz you should change the D filter value to 2 or 1 Temperature Calibration not required The OS5000 reports its temperature from the sensor inside of the modules 50 MIPS microprocessor It is affected slightly by the operating voltage of the module It may require a linear offset to make it align with ambient temperature Using the command lt esc gt ttt lt enter gt you can offset this temperature Enter the value in degrees Cx10 Example 25 will add 2 5 degrees C to the measurement 92 will deduct 9 2 degrees C Note This calibration step is not required and is for users looking for better temperature accuracy Calibration of Raw Magnetic readings in milliguass not required You can set the milligauss of the Horizontal earths magnetic field using the lt esc gt U mmmm enter This is milliguassx10 Example 1794 for 179 4 milligauss You can use the NOAA provided web model using your latitude and longitude and nanoTesla Horizontal for the earth s field in your local area Convert this to milligauss divide by 100 Make this change in compass settings before you calibrate the compass and the magnetic vector output will be in milliGuass NOAA Link M210 12 Mx121 21 My12 12 Mz171 1 M Vector Intensity Mx X component
33. sturbance Note You must have deviation set to O before this operation lt esc gt QO0 lt enter gt If you heading errors are very large before calibration i e too much soft iron very close to the compass you should not expect good results from calibration distance from the soft iron distortion is the best solution lt Esc gt S DEGUASS AND OFFSET RATE Degauss every n sentences This sets the frequency of the sensor degauss and offset operations The default value is something around 1 second lt Esc gt T The zero roll and pitch command will allow usets to zero out both roll and pitch This can only be done for applications where pitch and roll angles ate 3 degrees in a level platform Example Below C330 7P0 8R 1 3T19 9 04 C330 7P0 8R 1 3T19 9 04 CMD T Attempting to zero Roll Pitch Success Results above space Flash Write C330 8PO 0RO 0T19 9 2C C330 8PO 0RO 0T19 9 2C 19 lt esc gt Toggle between FACTORY DEFAULT SPACE and USER Space You can create a factory default calibration and default user settings by enter FACTORY space mode Setting parameters such as RATE BAUD clean calibration etc After all of these steps enter lt esc gt F which will restore factory to user space leaving FACTORY mode Now your users can do local calibrations escC escZ esc 2 and go back to your factory settings by typing escF at any point Note After each step that stores in FLASH i
34. t will say FACTORY if you re in the correct mode Important Note Some commands may not be available in earlier firmware releases Compass Mounting Guidelines In general you should mount the compass in a location in your vehicle or device that has the least disruption to the earth s magnetic field 1 2 3 4 5 6 Remember if a low cost needle compass gives large errors in your platform a very accurate compass will still measure these distorted fields with more accuracy Example Low cost compass finds a 20 degree distortion at 90 degrees due to soft iron we will find that this is actually 20 9 degrees Soft Iron correction will help but it can only do so much Mount away from permanent magnets such as motors The fields fall off as an inverse square of the distance so doubling the distance reduces the field strength by 1 4 soft iron fixed Mount the compass away from moving magnetic fields such as wires carrying current moving magnets generators etc soft iron dynamic Mount the compass as far as possible from batteries and ferrous materials such as iron and nickel Some aluminum is non ferrous but some AI alloys have nickel in them soft iron fixed Mount all compasses component side up side 1 with arrow level or true to platform level with the arrow pointing forward This is also the case when using the USB connector on the OS5000 USD Other orientations are supported but this needs to be selecte
35. th the Compass 15 Compass Command Summary Table ceceeeeeeeeeeeaeeeeeeeeeeeeeeeeeeeaeaaeaees 15 Compass Mounting Guidelines 23 wink kaa p eer ek eens 20 New Mounting Positioning with Firmware Version 1 5 and Later 22 Calibrating the COMPASS itu eter cio re reet Lora ber pac nest etae nee butt odd 25 Optional Soft Iron Calibration usse oo iv bon oe e oo oett reete fedes co Ee it nee tens 29 Installing Windows Demo Utility eeeeeeseeeeeeeeeeeeeee 33 USB Drivers for the OceanServer OS5000 USD family of compasses 35 Basic Commands to Configure the OS5000 seessseseses 36 Depth or other sensor Connection for OS5000 USD sseesesuss 37 PROGRAMMING NOTES Ss scenic sai ke Eve deco vi RW 38 Customer SUBD OM tete ds ot picti a E E est euin 41 OCEANSERVER COMPASS MANUAL Introduction to the Tiny Compass Family The OcceanServer preasion 3 Axas Tilt Compensated compass products use state of the art technology to provide outstanding performance and ease of use in a low cost design The OS5000 family of compasses are a new class of sensor components providing best in class performance for under 250 00 USD in volume Features Compass accuracy 0 5 degrees RMS heading while level 1 RMS lt 30 Tilt 1 5 RMS lt 60 Tilt undisturbed field 1 Degree resolution Roll amp Pitch full rotation typical 1 ac
36. that sets the filter period and the sampling update rate The lower the setting the faster the update rate can be If your using a 40hz output rate you should set this value from 3 to 2 lt esc gt D 1 9 enter to change the update rate 1 470 Hz 4ms settling time 2 242 Hz 8ms settling time 3 123 Hz 15 ms settling time factory default 62 Hz 32 ms settling time 50 Hz 40 ms settling time 39 Hz 48 ms settling time 33 2 Hz 60 ms settling time 19 6 Hz 101 ms settling time 90 dB rejection of 60Hz noise 16 7 Hz 120 ms settling time 90 dB rejection of 50Hz noise A 5 OCO a Gs Cn Use the higher values if you have large electrical or vibration noise you need to filter out at a much lower update rate 2 Averaging of readings n Sample in the average This will be a moving average filter of the magnetic readings and the accelerometer readings A value of 1 sample is no filtering the default is 6 with an output rate of 10 samples per second The output rate of samples per second combines with the number of samples in the average to give you the lag in response time of the output On the depth version OS5000 USDK this is set to 1 3 Output rate of the compass sentences n samples per second 31 Values that are negative are for less than one sample per second You can set this from 40 1 sample every 40 seconds to 2 1 sample every 2 seconds If the values are positive this is number of sample
37. ty of cables which come with the compass evaluation kits or can be ordered separately OS5000 USD will auto detect whether the Serial or USB cable has been plugged in Standard Cables 19 00061 24 24 OS5000 S Demo Kit Cable with Serial connection Pressure and 3 6V battery power connection picture below Demo cable provides 3 6V battery connection Cable Note this cable is a quick way to get the compass running for evaluation It is highly recommended that you operate the compass from 3 3V since the module has a linear regulator and a higher voltage than 3 3V heats up the module and wasting power and heating up the OS5000 module m 19 00062 24 24 OS5000 S Series Pigtail Cable 7 Pin connector blunt cut below OCEANSERVER COMPASS MANUAL 19 00116 00 Aprox OS5000 USD Demo Kit Cable with USB to 6 Pin connector There is also a 3 version available Firmware Updates for the OS5000 Compass Family Firmware updates can only be performed at the factory for the compass family You can get your compass firmware updated for 24 99 USD plus shipping back to you See out online store for details http www oceansetver stote com osfiuppr html 10 OCEANSERVER COMPASS MANUAL Communicating with the compass RS 232 or USB The USB compass requires device drivers to present itself to the system as an asynch serial port i e COMn port on Windows USB uses the FTEI chip FT230XQ We provide basic drivers and manuals on o
38. ue will add lag to the measurements but filter noise A value of D 1 provides the fastest update rate for compass data for example if you running at 40Hz update rate The value of D 3 is the default for the compass as it s shipped You will also get less resolution at D 1 and more noise in the dat lt Esc gt OUTPUT SENTENCE FORMAT Change Output Sentence Formats bit mask 1 2 4 8 16 are valid values Format 8 requires firmware version 1 4 or later and 16 version 1 6 or 17 later Default 1 2 is a simple NMEA like output with comma delimited data this is easy to tag and parse in user programs 4 is even simpler comma delimited data with no sentence NAME or handle lt Esc gt CHANGE ESCAPE CHARACTER careful Change Escape Character for compass default 27 ESC danger careful This is used to change the compasses ESCAPE character for applications where the compass may be on a shared output line and the system may send ASCII 27 characters If you change it you will not be able to talk to the compass unless you can send the new character value DON T CHANGE THIS UNLESS YOU ARE SURE HARDLY EVER NEEDED lt Esc gt F RESTORE FACTORY DEFAULTS Restore Factory Defaults and calibration lt Esc gt E COMPASS ORIENTATION Allows compass six mounting orientations to be set The mounting positions allow the user to mount the compass on all six sides on a box for placing in locati
39. ur web site for windows www ocean servet com compass At this point all compass designs present themselves as serial port devices at a baud rate 8 bits 1 stop bit ASYNCH Using a windows system open up a TeraTerm terminal emulator port to the compass device The factory default baud is 19200 8 1 N This change has been made so Windows OS does not mistakenly recognize the compass as a serial mouse The baud rate can be changed back to 9600 using the lt Esc gt B command Output Sentence Formats I cOM3 Tera Term VT 3 FS ni xl File Edit Setup Control Window Help SE LEUR SUE o MIA APUCLHTRHSSSNMS N TE CR HE SEA XN ES aaa fx utput Sentences 127 gt 15 alue and Enter or Esc 1 lash Write C212 4P2 5R 14 0T28 4Mx107977 90Mu 79422 00M2173 27Ax8 G45Ay B 245AzB 977 3A C212 4P2 SR 14 6128 5Mx187972 36Mu 79392 24M2173 240x0 0450 u 0 245020 9 78 34 CEIE MEASBR UESBTIB SHDCLHT9TI 2 1Ny 77358 49HEETS 4E XB BASH vB 2AB FORE fx utput Sentences 127 gt 1 and Enter or Esc 2 Write 212 4 2 5 14 0 28 4 107971 90 79328 18 173 28 0 045 80 245 0 978 x28 212 4 2 5 14 6 28 5 167976 26 79316 39 173 30 0 045 0 245 0 978 x24 213 4 2 5 14 80 28 5 107975 65 ure 02 173 32 0 045 80 246 0 978 25 212 4 2 5 14 8 28 5 107973 60 79261 95 173 380 0 045 0 245 0 978 24 212 4 2 5 14 0 28 5 107939 68 59260 61 173 32 0 045 80 246 0 978 29 212 4 2 5 14 8 28 5 187934 25 79268 47 173 29 0 045 8 245 0
40. with MSI pressure transducer sensor outputs 0 5 4 5V OceanServer compass has an internal series resistor divider to change voltage range to 0 2 5V GK 3K ohm series for its internal AD conversion Note User Supplies Regulated 5V DC to Pressure Sensor Pressure Output 0 5 4 5V to Pmi Note See page 7 for assignment of pins 3 7 OS5000 USD commands lt esc gt M nnnn lt enter gt enter max pressure for sensor PSI lt esc gt P lt space gt set zero depth pressure output via 24 bit AD resolution in 0 01 feet Note Depth assumes fresh water no internal density correction If MO lt enter gt is set the device will output the sensor voltage for use with non depth sensors One example would be an altitude sensor for airborne applications The depth calculation is simple and should be improved if you know the salinity Temp and Longitude of operation Depth feet PSI 2 31 If you want Pressure Pressure PSI depth ft 2 31 and then you can use more accurate calculations UNESCO algorithms and others http tesoutce npl co uk acoustics techguides soundseawater content html Remember the OS5000 USD pressure input white wire has an internal voltage divider to allow an external 0 5 4 5V signal to be input to the OS5000 USD s AD The resistance values are two 3K resistors in series to ground 6K resistance to ground The output of your sensor must consider this divider in it s output drive circuit The reason the range start
41. yro compass Moving average filter on roll pitch and heading Enter the number of samples to include in the average This combined with output rate will determine the period of the filter Example averaging 5 output rate 10 is half second period lt Esc gt V lt Esc gt FIRMWARE VERSION Displays the firmware version installed on this device CALIBRATE TEMPERATURE MEASUREMENT Calibrate Temperature offset in O 1C example lt esc gt 131 lt enter gt will subtract 13 1 from the reported temperature Temperature is a crude sensor and should not be used if accuracy is required it is a good relative measure of changes in the electronics rack lt Esc gt U SCALE MAGNETIC FIELD OUTPUT Calibrate and scale Raw Magnetic output milliguass of horiz field requires new calibration The value you enter is the local horizontal field strength of the earth s magnetic field After you enter this and do a calibration the compass will output 3 axis magnetic sensor values in milliguass The local H field strength can be estimated using the NOAA world magnetic model for you local area You are basically providing the compass with the value for the earth s horiz field strength when it s calibrated If you know this accurately you will get good results on the calibrated data lt Esc gt D DECIMATION FILTER FOR AD Digital Filter Value for AD conversion higher longer filter time The default value is 3 using a higher val
Download Pdf Manuals
Related Search