Digital Compass Users Guide, OS4000 Series
Contents
1. C69 6P 0 4R 90 0T27 0 24 C69 7P 0 4R 88 4T27 0 28 21 Visit OceanServer s download page for 3D Models and Mechanical Drawings www ocean server com download html D GND Pin 1 Q 635mm 9 025 s x20 20 6 35mrr holes RXD TIL mm 0 055 k Y I 15 2mm O 325 e t Sa5mm GND New Mounting Positioning with Firmware Version 1 5 and Later Please note Side 1 of OS4000 T compass model and North Firmware version 1 5 introduces 5 additional mounting positions for users that need the compass orientated differently in their product 22 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 23 Option 2 front above Option 3 Port above2. e Option 4 Roof above 24 Option 5 Back above N g Option 6 Starboard Calibrating the Compass 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 Hard iron Soft iron effects are caused by un magnetized ferrous materials in the area of the compass Hard Iron effects are caused by magnetized ferrous materials near the compass Hard Iron can be cancelled out by going through the rotational calibration described bellow Soft iron effects should be addressed during the design in phase and compasses should be located away from such items to minimize impact to the 25 Ferrous Material in Tail Plus an Electric Motor Creating Magnetic Field Disturbance Not an Ideal Place for Compass Placement 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 in the earlier table you will see that the placement of soft iron a small distance from the
3. 79282 02 173 32 0 045 0 246 0 978 x25 212 4 2 5 14 0 28 5 107973 60 79261 95 173 30 0 045 0 245 0 978 x24 212 4 2 5 14 80 28 5 107939 68 79260 61 173 32 0 045 80 246 0 978 29 212 4 2 5 14 0 28 5 107934 25 79268 47 173 29 0 045 0 245 0 978 x28 utput Sentences 127 gt 2 alue and Enter or Esc 4 lash Urite HCHDT 212 4 T 2C HCHDT 212 4 T 2C HCHDT 212 4 T 2C MD utput Sentences 127 gt 4 alue and Enter or Esc 8 lash Urite 12 4 2 5 14 0 28 6 107934 59 79258 69 173 27 0 045 8 244 0 9 78 12 4 2 5 14 0 28 5 107940 70 79263 87 173 25 0 045 80 244 0 9778 12 4 2 5 14 0 28 6 107929 16 79273 99 173 26 0 045 8 245 0 977 12 4 2 5 14 0 28 7 107929 85 79259 35 173 25 0 045 0 245 0 977 12 4 2 5 14 0 28 7 107939 34 79243 55 173 27 0 045 8 245 0 977 12 4 2 5 14 0 28 7 107954 94 79237 44 173 27 0 045 8 245 0 977 12 4 2 5 14 0 28 7 107937 20 79229 34 173 29 0 045 0 245 0 977 MD U TI lt C gt 22 Jan 2008 OS5888 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 11 OCEANSERVER COMPASS MANUAL 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 g
4. Compass 15 Compass Command Summary Table eeeeeeseesseessesssesseeseeess 15 Compass Mounting Guidelines eeeeeseessessesssssesesseeeeee eene 20 New Mounting Positioning with Firmware Version 1 5 and Later 22 Calibrating the Compass decise ose Danse Steueten auo BERI ota use Qaeda deest 25 Optional Sort Iron GallDFAllonss sui nals coders iecit e t eel d o 29 Installing Windows Demo Utility 2 suene doce E I UA TE DFPRR Ade dean anno Ee Sx Ps Ep eee eeuss 32 USB Drivers for the OceanServer OS4000 T Carrier Board 35 Basic Commands to Configure the OS4000 sssssmmmR 35 PROGRAMMING NOTES xciscnsuee d 0207248222600086 SU ce bea C eite nne 36 Customer SUPPO rcm e cence dde E pe Rene totum erbe bt L 39 OCEANSERVER COMPASS MANUAL Introduction to the OS4000 Nano Compass The OccanServer precision 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 OS4000 compass is a new high precision sensor providing OEM users with one of the world s tiniest fully featured compasses at a tiny price Features e Precision compass accuracy 0 5 degrees nominal 0 1 resolution e Roll amp Pitch full rotation lt 1 degree 0 60 degrees e Pitch Angles 90 degrees Roll Angles 180 degrees e Tilt compensated electronically gimb
5. Integer For Each Character In sentence Select Case Character 37 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 calculated checksum public bool IsValid string sentence Compare the characters after the asterisk to the calculation return sentence Substring sentence 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 Ignore the dollar sign else if Character 38 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 che
6. 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 31 You can set the milligauss of the Horizontal earths magnetic field using the lt esc gt U mmmm lt enter gt 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 http www ngdc noaa gov seg geomag jsp IGRFWMM jsp defaultModel WMM M210 12 Mx121 21 My12 12 Mz171 1 M Vector Intensity Mx X component 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 The G vect
7. Null Gyro no rotation Deviation N do sr B 1 Set Declination BE 1 Q Average Samples AD Decimation Filter 1 to 6 53A0 998 2F 55A0 998 2B 56A0 999 25 57A0 998 26 60A0 999 21 n m wo BERA ERE b o9 34 USB Drivers for the OceanServer OS4000 T Carrier Board You must download the USB drivers for windows directly from our web site These are only required if your using the USB interconnect option on the OS4000 M carrier board for the OS4000 T compass Remember if you have an OS4000 M it supports either RS 232 serial or USB by selecting the correct cable There ate 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 www silabs com CP210x VCP Drivers Drivers for Windows Mac and Linux Ele Edit EUG History Bookmarks Tools Help gt e ws tit Li http www ocean server com compass USBdrivers Getting Started EJ Latest Headlines G Google X Yahoo GlobalSpec ClientSe OCEAN Index of compass USBdrivers a Z Google Calendar Index of compass USBdrivers Name Last modified Size Description Parent Directory 08 Sep 2008 09 04 e Linux 08 Sep 2008 08 28 B macOS 08 Sep 2008 08 27 a windows 08 Sep 2008 08 30 m www ocean sefver com compass Our demo program runs on
8. com download html 36 TestComPort Running Microsoft Visual Studio lnlxl Fle Edt View Project Buld Debug Data Tools Window Community Help Poga Halk ua mm 1A iom CR ee ee n a GE 7E ee 152 ee Emm icis com oe Compass Demo HH S Properties H aaj References Azimuth Iv Maa S R GwoS app config V Pitch IV M Vect M Gyro Vect a E frmConfig cs KR Roll IV Acc S V Life Court H E frmMain cs I SPI Er Program cs Output Rat 20 H Sed Output Format lsolution Explorer iData Sources za C immediate Window 43 Error List Ready 4 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 downloaded in trial from Microsoft com NMEA CHECKSUM GENERATION 1 Example of checksum calculations in VisualBasic 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
9. compass can make huge differences Magnetic Field Examples C Non Ferrous Bow ompass Placement PeaccMenece Field Disturbance Best Place for Compass Placement 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 patity We recommend TeraTERM free software A Nema string of data will begin outputting when connected properly ie C328 3P28 4R 12 4121 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 field cats motots wires with cutrent magnets etc System board where Rotate 560 Degrees OS4000 T compass is Parallel to the Earth mounted 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 p
10. 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 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 Please contact OceanServer support directly for additional information and support for this format 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 suppott 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 8 128 Acceleration Vector Length 9 256 3 axis Acceleration Readings x y z 10 512 reserved 11 1024 2 axis Gryo Output X y 12 2048 Reserved 13 4096 Reserved OCEANSERVER COMPASS MANUAL Tabl
11. 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 28 basic steps ate 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 cutrents 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 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 follow 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
12. OCEANSERVER COMPASS MANUAL OceanYerver T EOHNOLGOZOGSY ING Digital Compass Users Guide OS4000 Series P N 90 05001 00 REVISION 1 1 2008 OceanServer Technology Inc 151 Martine St Fall River MA 02723 USA WWw Ocean server com Sales ocean server com or support Mocean setver com OCEANSERVER COMPASS MANUAL Table of Contents Introduction to the OS4000 Nano Compass ssse e 3 Os Compass Design Features aai uarie e na annir Ne ee ione e EREE 5 SPECCINCAHNONSG MEE CDD PONI IRE 5 Electrical Connector and pin assignment ssssemmmRRmn 7 Cables to Connect to the OS4000 M Carrier Board sssusssss 8 Communicating with the compass RS 232 or USB sususss 10 Ouiput Sentence Formats 5 dana nacen qaid sa ERR o Uode eua aoo qu im paa e ERE Eve dons 11 Format Type 0x01 1 10 C format eessesseeeeeenneeennnnnnnnnnn 12 Format Type 0x02 2 10 BOHPR Sentence iius sss 13 Format Type 0x04 4 10 HCHDT Sentence iiis s lt 13 Format Type 0x08 8 10 comma delimited Sentence 13 Format Type 0x10 16 10 Direct LCD Output eesseeeeeeeeeeeeeen 13 Output Parameter Selection Table ccccccccccssssessseeeeeeeeeeeeeseaeseeeeeseeeeeeeeaaas 14 Terminal Emulation Programs for Communicating with the
13. 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 it s NMEA strings Basic Commands to Configure the OS4000 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 35 j 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 lt esc gt V Check firmwate version lt esc gt B Set compass baud rate Active after power cycle lt esc gt C calibrate X Y rotate 360 in 15 seconds level X Y esc Z Calibrate X tip platform on side rotate 360 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 lt esc gt R set the output rate for your application lt esc gt set user sentence format 1 2 4 8 lt esc gt soft iron calibration align system to N S E W magnetic lt esc gt A Set averaging to smooth the readings Note These are the most common commands used configurations will vary PROGRAMMING NOTES OceanServer offers developers a Source Code Example Program that communicates with the OS5000 and OS4000 T compass under Windows This program can be downloaded from OceanServer download page http www ocean setver
14. aled e Nano size 0 6 x 0 6 weight 1 gram e Low Power Consumption lt 30ma 3 3V e Hard and soft iron compensation routines e Serial Interface o TTL o Baud rate programmable 4 800 to 115 000 baud e Rugged design o 10 000 G shock survival o 20C to 70C operating temperature 40C to 85C non op e ASCII sentence output in several formats NMEA checksum e High Data Update Rate to 40HZ e Support for True or Magnetic North Output e 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 o 50 MIPS processor supporting IEEE floating point math OCEANSERVER COMPASS MANUAL OS4000 T Signals TTL Levels 3 Axis Compass 0 6 x 0 6 size offers TTL only support through hole package OS4000 M Translator Carrier Board for Developers Signals USB or RS 232 This board is offered in the OS4000 T evaluation kits so users have a reference on how to hook up the module and create the holes in the user design to mount the OS4000 T The OS4000 M is only for initial development and debug The evaluation kit includes a user CD with the schematics and layout in the Eagle format Bottom Side Top Side f Evaluation Kit 054000 Camer Board Compass Factory default mounting positions shown below with and without carrier board user can also select five other orientation positions OCEANSERVER COMPASS MANUAL OS Co
15. alues Azimuth 1 Pitch 2 Roll 4 Temp 8 depth 16 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 http en wikipedia org wiki Magnetic declination Esc C CALIBRATE HARD IRON X Y SENSORS LEVEL PLANE OCEANSERVER COMPASS MANUAL 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 s 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 Z lt Esc gt H or or h CALIBRATE HARD IRON Z SENSOR ROLLED 90 Deg Rotate your platform 90 degrees on it s 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 HELP MENU Help Menu lt Esc gt A FILTER HEADING ROLL AND PITCH Moving average filter on roll pitch an
16. cksum with this character s value Checksum Checksum Convert ToByte Character Return the checksum formatted as a two character hexadecimal return Checksum ToString X2 Customer Support Send technical questions to support ocean server com OceanServer Technology Inc 151 Martine St Fall River MA 02723 USA Copyright 2008 by OceanServer Technology Inc All Rights Reserved 39
17. d 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 earths horiz field strength when it s calibrated If you know this accurately you will get good results on the calibrated data Esc D DECIMATION FILTER FOR AD Digital Filter Value for AD conversion higher longer filter time The default value is 3 using a higher value will add lag to the measurements but filter nois
18. e 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 data 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 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 Esc vy 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 locations where flat mounting is not possible These are shown graphically in a later s
19. e 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 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 TeraTerm Support Forum http www neocom ca forum viewtopic php t 436 The install for version 4 51 and can be locate at http www neocom ca freeware TeraTerm teraterm utf8 451 exe A windows version of Tera Term installer is located at www ocean setver com compass Compass Command Summary Table The compass is configured and calibrated using a set of commands sent to it via its serial port connection The general format of all commands to the compass ate sending it
20. ection of this manual Mounting options 1 6 E 1 Default flat 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 atise FW Version V1 5 FW_Date 1 Jul 08 Serial number 000765431 Test_date 01 Jan 08 Output_Format 1 Display_Fields 15 HW_Mounting_Pos 1 Baud_Rate 5 Set Reset_Rate 8 Output_Rate 40 Averagine 0 lt Esc gt SOFT IRON COMPENSATION The values are 0 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 disturbance Note You must have deviation set to 0 before this operation lt esc gt QO lt enter gt If you heading errors are very large before calibration i e too much soft iron very clo
21. erver offers a variety of cables which come with the OS4000 compass evaluation kit Once the OS4000 T is connected to the carrier module it will auto detect whether the Serial or USB cable has been plugged in OCEANSERVER COMPASS MANUAL Standard Cable Details 19 00061 24 24 OS5000 S and OS4000 M 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 recommended that you operate the compass from 3 3V 5V will operate with up to 18VDC using 3x the power 19 00062 24 24 OS5000 S T and OS4000 M Series Pigtail Cable 7 Pin connector blunt cut below OCEANSERVER COMPASS MANUAL 19 00116 00 Aprox 6 OS5000 US and OS4000 M Demo Kit Cable with USB to 6 Pin connector There is also a 3 version available Communicating with the compass RS 232 or USB The OS4000 is the exact hardware and firmware used on the OS5000 compasses the key difference is that it only supports a TTL level serial output The evaluation module the OS4000 M lets you plug in the OS4000 T and it generates VCC from an 10 OCEANSERVER COMPASS MANUAL input DC voltage that can be from 3 3V 18V DC The OS4000 M carrier also implements RS 232 drivers as well as the CP2102 USB to Serial bridge allowing you to interface via RS232 or USB for initial testing If you
22. have questions send e mail to support ocean servet com module compass requires device drivers to present itself to the system as an asynch serial port i e COMn port on Windows There are drivers supporting MAC OS and Linux variants on the www silabs com web site CP2102 bridge drivers We provide basic drivers and manuals on out web site for windows www ocean server 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 COM3 Tera Term VT 0 xj File Edit Setup Control Window Help utput Sentences 127 gt 15 alue and Enter or Esc 1 lash Write C212 4P2 SR 14 6128 4Mx107977 90M4u 79422 00M2173 270x80 0450 y 0 245020 9777 3R C212 4P2 SR 14 6128 5Mx187972 36Mu 79392 24M2173 248 x8 04580 u 0 245020 978 34 C2120420 ean 2 E c a 29121 n 205 REZI AE 2 ADB MAINE een eer peed utput Sentences 127 gt 1 and Enter or Esc Write 212 4 2 5 14 0 28 4 107971 90 79328 18 173 28 0 045 0 245 0 978 x28 212 4 2 5 14 80 28 5 107970 20 79316 39 173 30 0 045 8 245 0 978 x24 212 4 2 5 14 0 28 5 107975 65
23. l Data Interface TTL 4800 115000 baud 8 bit 1 stop no parity 19200 default Sentence Format Magnetic Routines Compensation NMEA0183 Style four sentence formats supporting xor parity SHCHDT OHPR C comma delimited Supports Acceleration amp Magnetic sensor output in X Y Z Hard Iron and Soft Iron calibrations supported OCEANSERVER COMPASS MANUAL Electrical Connector and pin assignment OS4000 T pin assignment also see page 22 drawing SK1 GND 0S4000 3 axis Compass Module GND VCC OceanServer OS4000 M Carrier Module Top side serial connector where the OS4000 T plugs in 7 pin Molex 1 25mm connector Molex 51021 0700 OCEANSERVER COMPASS MANUAL Pin Color Signal Description 1 White 2 Black GND Ground 3 Red Vin DC Power Input DC voltage in the range of Unreg 3 3V 5V 4 Orange NC RESERVED Do Not Connect 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 Bottom side connector for USB 6 pin single row header Molex 1 25mm connector Molex 53261 0671 Pin Color Signal Description 1 Green USB D 2 White USB D 3 Red 5V Regulated USB Power 4 Black Ground USB Power 5 Reserved Must be no connect 6 Reserved Must be no connect Cables to Connect to the OS4000 M Carrier Board OceanS
24. lus 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 27 have slowly rotated the device and observed the following output this indicates you have found the X Y max and X Y min values 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 Step 4 Z Calibration Rotate device 90 degrees so it is turned on its side Rotate 90 degrees Next rotate 360 degrees OS4000 T is mounted System board where g gt while at 90 degree angle gt A a L Z Calibration Roll the platform 90 degrees The area should be clear of soft and hard iron objects that could disrupt the earths 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 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
25. mpass Design Features Hardware OS4000 T TTL Only Magnetic Sensors Honeywell two axis AMR sensor for X Y plane sensing Honeywell z axis AMR sensor Accelerometer tilt sensor Three axis STM 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 Development Kit Items OS4000 M Translator Carrier Board includes signals USB or RS 232 This board is offered in the OS4000 T evaluation kits so users have a reference on how to hook up the module and create the holes in the user design to mount the OS4000 T The development kit includes the schematic and layout of the OS4000 M translator module Eagle Layout V4 16 Specifications Parameter Value Azimuth accuracy lt 0 5 deg RMS 0 1 deg resolution Inclination pitch and roll lt 1 deg 0 1 deg resolution OCEANSERVER COMPASS MANUAL Inclination range 80 degrees output for full rotation at decreased accuracy pitch 90 degrees roll 180 degrees Temperature range 40C to 85C operating 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 0 6 x 0 6 module Weight 1 gram Supply Voltage 3 3V 5VDC Will operate with up to 18VDC using 3x the power Power consumption 30 ma 3 3V Seria
26. ng 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 0 0 OQ UT E 0 N 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 3 Output rate of the compass sentences n samples per second Values that ate 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 samples per second The range 1s 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 OS4000 reports its temperature from the sensor inside of the modules 50 MIPS microprocessor It is affected slightly by the operating voltage of the module
27. non ferrous but some Al alloys have nickel in them soft iron fixed 5 Mount all OS4000 compasses component side 1 up level or true to platform level north should be forward see below Other orientations can be selected by using the command key E Side 1 Shown 6 Mount the compass in a mechanically stable location so this it moves with the vehicle or device but doesn t vibrate 7 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 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 gravity to detect level and tilt with accelerometers to measure tilt including OceanServer compasses The tilt angles are 20 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
28. or 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 setver com compass Installing Windows Demo Utility The windows demo utility is located on the web Download the CompassUtility24 exe file and open it This installer will put the compass demo program on your system www Oocean server com comnpass 32 M T e KJ fit L http www ocean server com compass Getting Started EV Latest Headines G Google Y Yahoo GlobalSpec Clentse L Index of compass 3 C Google Calendar Index of compass Name Last modified Size Descript Parent Directory 08 Sep 2008 13 45 CableSpecs zip 05 Mar 2008 12 06 129k CompassCsourceExampl gt 08 Sep 2008 09 03 83k CompassUtilityV24 exe 08 Sep 2008 09 00 3 1M Compass v2 4 exe 08 Sep 2008 08 35 3 1M Manuals zip 05 Mar 2008 13 26 1 8M USBdrivers 05 Mar 2008 12 13 archivefiles 08 Sep 2008 08 58 BOO cr Fp FR cr Gr ty tera
29. ore inline 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 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 OS4000 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 that sets the filter period and the sampling update rate 30 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 470 Hz 4ms settling time 242 Hz 8ms settling time 123 Hz 15 ms settling time factory default 62 Hz 32 ms settling time 50 Hz 40 ms settli
30. reater than 0 are in sentences per second HZ A value of 10 is 10hz 40 is 40hz and so on If you program a rate 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 000Mz0 000Ax000 0Ay000 0Az000 0 cc C212 4P2 5R 14 0T28 4Mx107977 90My 79422 00Mz173 27Ax0 045Ay 0 245A20 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 1f one 1s entered Ppp p Pitch angle P precedes the pitch angle in degrees Rrr rr Roll angle R precedes the roll angle in degrees Ttt t 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 OS4000 T 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 s
31. se to the compass you will continue to have error with very disturbed magnetic fields The best solution is distance from soft iron in this case Esc 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 The quicker you degauss the lower the compass lag is when moving it quickly 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 earths magnetic field 1 Remember if a low cost needle compass gives large errors in your platform a vety 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 can only do so much 2 Mount away from permanent magnets such as motors The fields fall off as inverse squate of the distance so doubling the distance reduces the field strength by 1 4 soft iron fixed 3 Mount the compass away from moving magnetic fields such as wires carrying current moving magnets generators etc soft iron dynamic 4 Mount the compass as fat as possible from batteries and ferrous materials such as iron and ni Some aluminum is
32. 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 29 B COM4 Tera Term VT File Edit Setup Control Window Help C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 5 22 C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 4 23 C358 8P8 5R8 0T18 4 23 LIEU BOURIAM MAS oft Iron 8 Off 1 On 2 Calibrate 2 gt 6 alue and Enter or Esc lign platform exactly North degrees then hit Space Bar lign exactly East 98 degrees then hit Space Bar gt lign exactly South 188 degrees then hit Space Bar gt lign exactly West 270 degrees then hit Space Bar gt ft Iron Ualues 0 8 1T18 4 x01 C348 9PB 3R 8 1T18 4x01 8 3T18 4 805 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 m
33. term utf8 451 exe 14 Ju1 2008 06 25 3 8M Main Screen OceanServer Digital Compass Demo Utility v2 1 X Configure Open Por Close Port OceanServer TECHNOLOGY INC S Heading 319 9 Pitch 0 1 Roll 43 4 33 Configuration Screen Setup Setup for Digital Compa r Graphic Charts Serial Com Input Port EXTR gt r Port Config Baud Rate 12200 Parity Nene Data Bits e z Stop Bits fi r Magnetic Chart Min Max g r Acceleration Chart Min Max Program Screen allows for calibration custom screen displays and other settings OceanServer Digital Compass Demo Utility V2 1 Configure Open Port Close Port Output 8 3 Calibration X Y Compass Level c Calibrate 2 Compass 90 Degrees Start z Show v Azimuth Depth Acc Vect Range 180 0 180 0 Terminal Window V Show Compass Output 56Mx 80 45My 160 86Mz71 57Mx 80 46My 160 86M271 58Mx 80 45My 160 86M271 58Mx 80 45My 160 86M271 58Mx 80 46My 160 85M271 Baud Rate 9600 z samples s Restore FACTORY Defaults Output Rate 50 40 Iv Pitch Iv Mag S Gyros Vv Roll v M vect Gyro Vect Max Pressure 100 PSI VV Temp W Acc S M Life Count PSI Deguass every sentences S Zero Depth at surface iation
34. the ESCAPE command key ASCII 27 decimal noted as lt esc gt in this manual Typet lt esc gt Kvalue lt space gt Type2 lt esc gt K OCEANSERVER COMPASS MANUAL 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 such as heading we send it 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 Esc key prior to a key command The command keys are CASE sensitive so if it asks for a R a r will not work Note2 Some command changes require the compass to be power cycled for changes to take affect Example BAUD RATE CHANGE Key Command Esc B Description of the command 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 lt Esc gt X 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 OUTPUT DATA FIELD SELECTION Fields to Display bit mask of 5 bits entered in decimal 31 all active Sum up the v
35. 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 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 C288 6P 0 2R 0 1T26 6 20 C288 4P 0 2R 0 2126 6 21 C288 6P 0 2R 0 2126 6 23 Notice Level in roll and pitch CMD C Bridge offset Calibrate X Y space when done XyxXyXyXNYXyXyNX XXYxYY xYxYxYxYxYxYxYxY xYxYxYxYxYxYxY xYxYxYxYxYxYxYx YYxYxYxYx YxYY YYYYYYYY YYXYXXYXYXX XXXXXXX XXXXXXXX XXXXXXXXXyy XXX XXX X Y YYY YY YY XS rer ads nie Flash Write C346 7P1 5R 0 1T26 9 06 C335 7P 0 3R 90 0T26 9 10 C335 7P 0 4R 88 4126 9 1A C335 7P 0 4R 90 0126 9 17 Notice Platform rolled 90 degrees pitch 0 CMD Z Bridge offset Calibrate Z space when done aA zu AL LLALLLLLLL A Le LELLELLELLL LAL LLLLL LLL LEU LILLOLIDIULELILIL LEDTULLLELLILIELD DD ZZZZZZZZZZ ZZ Flash Write
36. trength 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 character the cc is the HEX X OR sum of the characters between the and the This is the NMEA standard format OCEANSERVER COMPASS MANUAL Format Type 0x02 2 10 S OHPR Sentence SOHPR value 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 HCHDT 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 valuet 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 elements selected in
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