this version has all of Jim's fixes for reading the GPS and IMU data synchronously
Dependencies: MODSERIAL SDFileSystem mbed SDShell CRC CommHandler FP LinkedList LogUtil
main.cpp
- Committer:
- jekain314
- Date:
- 2013-06-21
- Revision:
- 26:c2208b0ff78b
- Parent:
- 25:2287bd8c9877
- Child:
- 27:94a6f0589993
File content as of revision 26:c2208b0ff78b:
#include "mbed.h" #include <string> //set up the message buffer to be filled by the GPS read process #define MODSERIAL_DEFAULT_RX_BUFFER_SIZE 256 #include "MODSERIAL.h" #include "SDFileSystem.h" //imported using the import utility //general digital I/O specifications for this application //SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name); SDFileSystem sd(p11,p12,p13,p14,"sd"); DigitalIn sd_detect(p27); DigitalOut ppsled(LED1); //blink an LED at the 1PPS DigitalOut trig1led(LED2); //blink an LED at the camera trigger detection DigitalOut rxMsg(LED3); DigitalOut txMsg(LED4); //DigitalOut recordDataled(LED4); //set the led when the record is on //hardware trigger mechanization for bulb shutter commands DigitalInOut fire(p29); //connected to the tip of 2.5mm connector (T2i) DigitalInOut pre_fire(p30); //connected to the mid-connection for 2.5mm connector (T2i) //USB serial data stream back to the PC Serial toPC(USBTX, USBRX); //connect the GPS TX, RX to p9 and p10 Timer timeFromStart; Timer timeFromPosVelMessageReceipt; bool detectedGPS1PPS = false; //flag set in the ISR and reset after processing the 1PPS event int PPSCounter = 0; //counts the 1PPS occurrences int byteCounter = 0; //byte counter -- zeroed at 1PPS unsigned short perSecMessageCounter=0; //counts the number of messages in a sec based on the header detection bool messageDetected = false; //have detected a message header unsigned long IMUbytesWritten = 0; //counts the IMU bytes written by the fwrite() to the SD card int savedByteCounter = 0; //save ByteCounter at the 1PPS for display in main int savedPerSecMessageCounter=0; //saved PerSecMsgCounter for display in main int savedIMUClockCounter=0; //saved at the 1PPS for later diaplay from main bool camera1EventDetected = false; //flag from ISR indicating a clock event occurred double camera1Time; //GPS time of the camera event int TotalBadCRCmatches = 0; //counter for the bad CRC matches for all GPS messages volatile int PPSTimeOffset = 0; ////////////////////////////////////////////////////////////////////// // the below should become classes ////////////////////////////////////////////////////////////////////// #include "OEM615.h" //OEM615 GPS activities #include "ADIS16488.h" //ADIS16488 activities #include "PCMessaging.h" //PC messaging activities // stuff to send the SD file to the PC #include "SDShell.h" void transferFile() { SDShell emulate; // create the object emulate.init(); // init the params inside GPS_Reset = 0; // low power PCB mode ADIS_RST = 0; // same here wait(0.01f); // just make sure that the hardware has time to stop fflush(stdout); // and clear any TX reminants toPC.printf("Entering Shell Emulator...\n"); // just for fluf wait(0.1f); // no reason for this either emulate.shell(toPC, sd, "/sd"); // now the SDShell object will serve SD files via UNIX commands } //ISR for detection of the GPS 1PPS void detect1PPSISR(void) { timeFromPPS.reset(); //reset the 1PPS timer upon 1PPS detection //note -- the below accounts for time information becoming available AFTER the 1PPS event PPSTimeOffset++; //counts 1PPS events between matching POS and VEL messages //covers the case where the PPS ISR interrupts the IMU data ready ISR if(IMUDataReady) IMUtimeFrom1PPS = 0; savedByteCounter = byteCounter; //save byteCounter for display in main savedPerSecMessageCounter = perSecMessageCounter; //save for display un main byteCounter = 0; //countes bytes between 1PPS events perSecMessageCounter = 0; //counts GPS messages between 1PPS events GPS_COM1.rxBufferFlush(); //flush the GPS serial buffer detectedGPS1PPS = true; //set false in the main when 1PPS actions are complete PPSCounter++; //count number of 1PPS epoch ppsled = !ppsled; //blink an LED at the 1PPS }; /////////////////////////////////////////////////////// //set up the USB port and the GPS COM port /////////////////////////////////////////////////////// FILE *fpNav = NULL; //file pointer to the nav file on the SD card void setupCOM(void) { //system starts with GPS in reset active //dis-engage the reset to get the GPS started GPS_Reset=1; wait_ms(1000); //establish 1PPS ISR PPSInt.rise(&detect1PPSISR); //set the USB serial data rate -- rate must be matched at the PC end //This the serial communication back to the the PC host //Launch the C++ serial port read program there to catch the ASCII characters //toPC.baud(9600); wait_ms(100); toPC.baud(8*115200); wait_ms(100); //toPC.baud(1*115200); wait_ms(100); //toPC.printf("\n\n released GPS from RESET and set to high baud rate \n\n"); //just wait to launch the GPS receiver for (int i=0; i<5; i++) { toPC.printf("WMsg start: %3d \n", 4-i); wait(1); } sd_detect.mode(PullUp); if (sd_detect == 0) { mkdir("/sd/Data", 0777); } else { toPC.printf("WMsg SD card not present \n"); } //NOTE: we do not assume that the GPS receiver has been pre-set up for the WALDO_FCS functionality //we alwsys start with a reset and reprogram the receiver with our data out products // this prevents failure because of a blown NVRAM as occurred for the older camera systems //this is the COM1 port from th GPS receiuver to the mbed //it should be always started at 9600 baud because thats the default for the GPS receiver GPS_COM1.baud(9600); wait_ms(100); // this ASCII command sets up the serial data from the GPS receiver on its COM1 char ch7[] = "serialconfig COM1 9600 n 8 1 n off"; // this is a software reset and has the same effect as a hardware reset (why do it?) //char ch0[] = "RESET"; //this command stops all communication from the GPS receiver on COM1 //logs should still be presented on USB port so the Novatel CDU application can be used on the PC in parallel char ch1[] = "unlogall COM1"; //set the final baud rate that we will use from here //allowable baud rate values: 9600 115200 230400 460800 921600 //char ch2[] = "serialconfig COM1 921600 n 8 1 n off"; char ch2[] = "serialconfig COM1 115200 n 8 1 n off"; //the below commands request the POS, VEL, RANGE, and TIME messages char ch3[] = "log COM1 BESTPOSB ONTIME 1"; //messageID = 42 char ch4[] = "log COM1 BESTVelB ONTIME 1"; //messageID = 99 char ch5[] = "log COM1 RANGEB ONTIME 1"; //messageID = 43 //char ch6[] = "log COM1 TIMEB ONTIME 1"; //messageID = 101 //set up VARF to be 100Hz with 1X10^4 * 10^-8 = 10^-4 sec (10usec) pulse width //in fact, we do not use this output but it is available. //originally planned to use this to command the IMU data //char ch8[] = "FREQUENCYOUT enable 10000 1000000"; //toPC.printf("WMsg set serial config \n"); sendASCII(ch7, sizeof(ch7)); wait_ms(500); //sendASCII(ch0, sizeof(ch0)); //toPC.printf("WMsg unlog all messages \n"); sendASCII(ch1, sizeof(ch1)); wait_ms(500); //toPC.printf("WMsg log BESTPOSB on COM1 \n"); sendASCII(ch3, sizeof(ch3)); wait_ms(500); //toPC.printf("WMsg log BESTVELB on COM1\n"); sendASCII(ch4, sizeof(ch4)); wait_ms(500); //toPC.printf("WMsg log RANGEB on COM1\n"); sendASCII(ch5, sizeof(ch5)); wait_ms(500); //toPC.printf("log TIMEB om COM1 \n"); //sendASCII(ch6, sizeof(ch6)); wait_ms(100); //toPC.printf("Set up th VARF signal \n"); //sendASCII(ch8, sizeof(ch8)); wait_ms(500); //set GPS output COM1 to the final high rate //toPC.printf("WMsg set the COM ports to high rate\n"); sendASCII(ch2, sizeof(ch2)); wait_ms(500); //set the mbed COM port to match the GPS transmit rate //the below baud rate must match the COM1 rate coming from the GPS receiver GPS_COM1.baud(115200); wait_ms(500); //without this wait -- the baud rate is not detected when using MODSERIAL //GPS_COM1.baud(921600); wait_ms(500); //without this wait -- the baud rate is not detected when using MODSERIAL }; ///////////////////////////////////////////////////////////////////// // mbed main to support the Waldo_FCS ///////////////////////////////////////////////////////////////////// int main() { //these are structures for the to GPS messages that must be parsed MESSAGEHEADER msgHdr; OEM615BESTPOS posMsg; //BESTPOS structure in OEMV615.h that has matching time to a BESTVEL message OEM615BESTPOS curPos; //BESTPOS structure in OEMV615.h OEM615BESTVEL velMsg; //BESTVEL structure in OEMV615.h that has matching time to a BESTPOS message OEM615BESTVEL curVel; //BESTVEL structure in OEMV615.h fire.output(); //set the fire pin as outoput pre_fire.output(); //set the pre-fire pin as output //fire.mode(OpenDrain); //set up for the first trigger fire = 1; pre_fire = 1; //set up the GPS and mbed COM ports setupCOM(); //set up the ADIS16488 setupADIS(); setUpMessages(); //set up the expected text message commands from the PC //initiate the interrupt to catch the GPS receiver serial bytes as they are presented GPS_COM1.attach(&readSerialByte, MODSERIAL::RxIrq); timeFromPPS.start(); //start the time for measuring time from 1PPS events timeFromStart.start(); //toPC.printf("\n\n top of the main loop \n\n"); int totalBytesWritten = 0; /*establish the initial value for the CRC recursion after the header signature bytes unsigned long CRC = 0; CRC32Value(CRC, 0xAA); CRC32Value(CRC, 0x44); CRC32Value(CRC, 0x12); CRC32Value(CRC, 0x1C); //this results in a value of: 0x39b0f0e1 toPC.printf(" CRC after AA44121C header: %08x \n", CRC); wait(20); */ //at the start we do not record the data recordData = false; sendRecData = false; unsigned long cyclesPerSec = 0; //main while() loop cycles per GPS sec bool GPSdataWritten = false; bool finishTrigger = false; Timer triggerInterval; //while(PPSCounter < 300) bool newMission = true; /////////////////////////////////////////////////////////////////////////// // top of the mission while loop /////////////////////////////////////////////////////////////////////////// while(newMission) { //read the USB serial data from the PC to check for commands readFromPC(); //this will close the fpNav file on the SD card if the file is open //and the elapsed time from PosVel messages is > 60 secs //this prevents loosing the fpNav file if the PC goes down // !!!! timeFromPosVelMessageReceipt !!! was never started if (fpNav && (timeFromPosVelMessageReceipt.read() > 10) ) { sendRecData = true; recordData = false; } // for any received PC message, take the appropriate action processPCmessages(fpNav, posMsg, velMsg); //if we receive a "GETFILE" message from the PC -- close the fpNavFile and break from the while() loop if (get_file_msg) { if (fpNav != NULL) fclose(fpNav); break; //terminate the while loop when we receive this message from the PC } if(fireTrigger) //comes from a PC request message { unsigned long triggerTime = GPSTimemsecs + PPSTimeOffset*1000.0 + timeFromPPS.read_us()/1000.0; toPC.printf("WMsg TRIGGERTIME %10d \n", triggerTime); //pre-fire the trigger using the mid-body 2.5mm connection (T2i) pre_fire = 0; //pin30 (midbody of connector) set to zero wait(.01f); // not sure what this does fire = 0; //fire the trigger using the tip connection fireTrigger = false; //finished the setup -- but wait to do the actual fire finishTrigger = true; //set to false after firing the trigger triggerInterval.start(); } //the trigger requires a pulse -- the above portion lowers the signal and the below raises it //this has been tested at 50 msecs and it will not fire at that pulse duration if(finishTrigger && triggerInterval.read_ms() > 100) { fire = 1; pre_fire = 1; triggerInterval.reset(); finishTrigger = false; //completes the trigger firing pulse definition } cyclesPerSec++; //////////////////////////////////////////////////////////////////////////// //below is where we process the complete stored GPS message for the second //The !IMUDataReady test prevents the IMU and GPS data from being written //to disk on the same pass through this loop ///////////////////////////////////////////////////////////////////////////// //there are three potential messages and all messages have a header if (completeMessageAvailable && !IMUDataReady) { //must unpack header first to get the message length msgHdr = *((MESSAGEHEADER*)&msgBuffer[messageLocation[savedMessageCounter-1]]); //these times are used to tag the IMU sample time. PPSTimeOffset increments by 1 exactly at the 1PPS event (in the 1PPS ISR) //GPSTimemsecs increments by 1 for each new GPS measurement -- note that the below computations are actually //done at the receipt of each GPS message. This is OK because each message has the same time in its header. //Thus GPSTimemsecs increments by 1 here while GPSTimemsecs effectively decrements by 1. //This handles IMU time tagging between the 1PPS event and the first receipt of a new GPS time. //message header length is 28 -- right side is pointer to the receiver-computed CRC for this record //CRC is computed while reading in the GPS bytes unsigned long msgCRC = *((unsigned long*)&msgBuffer[messageLocation[savedMessageCounter-1] + 28 + msgHdr.messageLength]); //toPC.printf("tmeFrom1PPS= %5d ID= %3d Ln = %3d computedCRC= %08x msgCRC= %08x msgCntr = %3d CRCerr=%4d\n", // timeFromPPS.read_us(), msgHdr.messageID, msgHdr.messageLength, computedCRC, msgCRC, savedMessageCounter, TotalBadCRCmatches); if ( msgCRC == computedCRC) //computedCRC is performed as we read each bvyte { //if the CRC check is valid -- then get the time from the header //we get three messages each sec -- does it matter that we do this three times? GPSTimemsecs = msgHdr.GPSTime_msecs; //time in GPS message header //the PPSTimeOffset accounts for the occurrence where we do not get any GPS messages over a sec -- but PPS is still operative PPSTimeOffset = 0; //incremented by 1 in the PPS ISR //We need the pos and vel messages to pass back data to the PC -- error cases that can occur: // (1) missed 42 (POS) -- use last good pos and extrapolate using last good vel // (2) missed 99 (VEL) -- use the last good vel since likely not changed much // (3) missed both 42 and 99 -- must use last good position and extrapolae using last good velocity // GPS time used to time-tag the IMU data and to do the extrapolttion from last good position to send to PC // in the position extrapolation, we will use the GPS time that is kept in the header of the POS msg (42) // see the procedure: sendPosVelMessageToPC() if (msgHdr.messageID == 42) //this is the position message (lat, lon, alt) { //map the starting record byte index to the record structure curPos = *((OEM615BESTPOS*)&msgBuffer[messageLocation[savedMessageCounter-1]]); posMsg = curPos; if (streamPos) // we no longer use this functionality { toPC.printf("BESTPOS %5d %1d %8.6lf %9.6lf %5.3lf %d %d\n", curPos.msgHeader.GPSTime_msecs, curPos.solStatus, curPos.latitude, curPos.longitude, curPos.height, curPos.numSV, curPos.numSolSV); } } else if (msgHdr.messageID == 99) //this is the velocity message { curVel = *((OEM615BESTVEL*)&msgBuffer[ messageLocation[savedMessageCounter-1] ]); //toPC.printf("BESTVEL vel: horizontalSpeed= %5.3f heading=%5.1f verticalSpeed=%4.2f \n", // curVel.horizontalSpeed, curVel.heading, curVel.verticalSpeed ); velMsg = curVel; } //below is set to true when we detect that we have received a complete GPS message completeMessageAvailable = false; } else // do this if we do not pass the CRC { toPC.printf("WMsg bad CRC match for messageID %3d total CRC errors = %4d \n", msgHdr.messageLength, TotalBadCRCmatches++); } } //write the GPS data to the SD card //NOTE: this is valid only for a once-per-sec GPS message //for this case, all messages come out well prior to 0.5 secs after the 1PPS if (!IMUDataReady && !GPSdataWritten && timeFromPPS.read_us() > 500000 && recordData && (fpNav != NULL)) { totalBytesWritten += fwrite(&msgBuffer, 1, byteCounter, fpNav); GPSdataWritten = true; } //the IMU data record is read from the SPI in the ISR and the IMUDataReady is set true //we write the IMU data here if (IMUDataReady) //IMUDataReady is true if we have a recent IMU data record { //write the IMU data if ( recordData && (fpNav != NULL) ) { //delTimeOfWrite = timeFromStart.read_us(); if (fillingPingWritingPong) totalBytesWritten += fwrite(&imuPong, 1, IMUrecArraySize*sizeof(IMUREC), fpNav); else totalBytesWritten += fwrite(&imuPing, 1, IMUrecArraySize*sizeof(IMUREC), fpNav); //delTimeOfWrite = (unsigned long)((unsigned long)timeFromStart.read_us() - delTimeOfWrite); //if (delTimeOfWrite > maxWriteTime) maxWriteTime = delTimeOfWrite; } IMURecordCounter+=IMUrecArraySize; IMUDataReady = false; } //this is a command from the PC to fire a trigger if (camera1EventDetected) //we have detected a camera trigger event { toPC.printf("WMsg TRIGGERTIME %5.3lf\n", camera1Time); camera1EventDetected = false; } if (detectedGPS1PPS) //true if we are exactly at a 1PPS event detection { //toPC.printf("PPS=%4d stat=%1d bytes=%3d GPSMsgs=%2d #write=%8d cycles=%6d\n", // PPSCounter, posMsg.solStatus, savedByteCounter, savedPerSecMessageCounter, // totalBytesWritten, cyclesPerSec ); cyclesPerSec = 0; //totalBytesWritten = 0; GPSdataWritten = false; //toPC.printf(" bytesWritten = %5d \n", totalBytesWritten); IMURecordCounter = 0; detectedGPS1PPS = false; rxMsg = !rxMsg; //flash the lights to make sure the mbed loop is operative txMsg = !txMsg; } /////////////////////////////////////////// } //end of the major while() loop /////////////////////////////////////////// if (fpNav != NULL) { fclose(fpNav); //insurance toPC.printf("WMsg closeFPNav \n"); } toPC.printf("WMsg totalBytesWritten %5d \n", totalBytesWritten); wait_ms(100); //send the nav file to the PC transferFile(); //rxMsg = txMsg = 0; // just indicate that we're in here // to exit this function the HOST (ie: computer or PC app) must send "exit" otherwise the mbed will act // like a terminal and serve SD file data forever toPC.printf("WMsg normalTermination \n"); wait_ms(100); NVIC_SystemReset(); }