james kain
JEK changes enabling proper recording of IMU/GPS datastrams - 02-APR-2013
Fork of
GPS_Incremental
by 
Dan Matthews
Diff: main.cpp
- Revision:
- 4:68268737ff89
- Parent:
- 3:5913df46f94a
- Child:
- 6:2a8486283198
--- a/main.cpp Fri Mar 22 01:33:24 2013 +0000
+++ b/main.cpp Fri Mar 29 20:52:24 2013 +0000
@@ -11,6 +11,8 @@
#include "ADIS16488.h"
#include <string>
+//these are defines for the messages that are sent from the PC across the USB
+//these messages produce reactions on the mbed
#define STATUS_MSG 0
#define POSVEL_MSG 1
#define STARTDATA_MSG 2
@@ -19,33 +21,39 @@
#define STOPSTREAM_MSG 5
#define STARTLOGINFO_MSG 6
#define STOPLOGINFO_MSG 7
+
#define DEGREES_TO_RADIANS (3.14519/180.0)
-//general items for this application
+//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");
//Serial debug(USBTX, USBRX); // tx, rx USB communication to the PC for debug purposes
-DigitalOut ppsled(LED1);
-DigitalOut trig1led(LED2);
-DigitalOut recordDataled(LED4);
-InterruptIn camera1Int(p30);
-DigitalOut camera2Pin(p29);
+DigitalOut ppsled(LED1); //blink an LED at the 1PPS
+DigitalOut trig1led(LED2); //blink an LED at the camera trigger detection
+DigitalOut recordDataled(LED4); //set the led when the record is on
+InterruptIn camera1Int(p30); // camera interrupt in
+DigitalOut camera2Pin(p29); // i dont believe we use the second camera interrupt
//USB serial data stream back to the PC
Serial toPC(USBTX, USBRX); //connect the GPS TX, RX to p9 and p10
-bool detectedGPS1PPS = false;
-bool recordData = false;
-int PPSCounter = 0;
-int byteCounter = 0;
-unsigned short perSecMessageCounter=0;
-bool lookingForMessages = true;
-bool messageDetected = false;
-int savedIMUClockCounter=0;
+bool detectedGPS1PPS = false; //flag set in the ISR and reset after processing the 1PPS event
+bool recordData = false; //set to true when commanded from the PC
+int PPSCounter = 0; //counts the 1PPS occurrences
+int byteCounter = 0; //byte counter -- where used??
+unsigned short perSecMessageCounter=0; //counts the number of messages in a sec based on the header detection
+bool lookingForMessages = true; //set in the PPS ISR and set false after the message processing in the main
+bool messageDetected = false; //have detected a message header
+int savedIMUClockCounter=0;
+unsigned long IMUbytesWritten = 0;
+int savedByteCounter = 0;
+int savedPerSecMessageCounter=0;
int IMUClockCounter = 0;
bool camera1EventDetected = false;
double camera1Time;
char serBuf[128];
int serBufChars=0;
+
+//flags to control the PC command actions
bool sendPosVel=false;
bool sendStatus=false;
bool sendRecData=false;
@@ -54,41 +62,69 @@
bool logMsgInfo=false;
bool sendLogMsgInfo=false;
-
//ISR for detection of the GPS 1PPS
void detect1PPSISR(void)
{
- timeFromPPS.reset();
- savedIMUClockCounter = IMUClockCounter;
- IMUClockCounter = 0;
- GPS_COM1.rxBufferFlush();
+ timeFromPPS.reset(); //reset the 1PPS timer upon 1PPS detection
+ savedIMUClockCounter = IMUClockCounter; //number of IMU clocks received since last 1PPS
+ savedByteCounter = byteCounter;
+ savedPerSecMessageCounter = perSecMessageCounter;
+ IMUClockCounter = 0; //counts number of IMU samples between 1PPS events
+ GPS_COM1.rxBufferFlush(); //flush the GPS serial buffer -- likely not needed but OK
+ byteCounter = 0;
+ perSecMessageCounter = 0;
- detectedGPS1PPS = true;
- lookingForMessages = true;
- PPSCounter++;
- PPSTimeOffset++;
- ppsled = !ppsled;
+ detectedGPS1PPS = true; //reset in the main when 1PPS actions are complete
+ lookingForMessages = true; //means we should begin looking for new GPS messages
+ PPSCounter++; //count number of 1PPS epochs
+ PPSTimeOffset++; //counts the 1PPS events between occurrences when we have matching POS and VEL messages
+ ppsled = !ppsled; //blink an LED at the 1PPS
};
//ISR for detection of the hotshoe trigger 1
void camera1ISR(void)
{
+ //PPSTimeOffset keeps track of missed
camera1Time = GPSTime + (double)PPSTimeOffset + timeFromPPS.read();
- trig1led = !trig1led;
- camera1EventDetected = true;
+
+ trig1led = !trig1led; //blink an LEWD at the camera event detection
+ camera1EventDetected = true; //reset to false in main after processing the image detection
};
void readFromPC()
{
+
+ //better solution
+ //start a timer when we get a char from the PC and set a bool: detectingPCMessage = true
+ //keep reading bytes until elapsed time from the first byte is : 0.01 secs of numByes > 16
+ //the messages are from 10 to 16 bytes -- this will take from 10/921600 to 16/921600 secs at 921600 baud
+ //8*115200 = 921600
+ //this is about 2e-5 or 20usec.
+ //so we could wait 50usec from the first char reeived and be certain we had all the chars for a message.
+ //the steps are below ....
+ //(1) convert this procedures to a ISR per byte
+ //(2) in the ISR, start the timer on the first byte received when !detectingPCMessage
+ //(3) set detectingPCMessage = true
+ //(4) in the main loop, test the timer for >50usec and parse the bytes to test fr a message
+ //(5) reset the timer to zero in the main loop after parsing the message
+ //(6) set detectingPCMessage = false;
+
+ //The received commands obnly occur at the initialization stage -- time is not that critical there.
+ //during the real-time action, we will never pass the followong if test ( no characters received)
if (toPC.readable()) //read a PC serial byte and test it for a command
{
// Read in next character
char inChar = toPC.getc();
serBuf[serBufChars++] = inChar;
+
// Append end of string character
+ //why do this for every character we read?
+ //answer: we always assume we have a complete message and test for this below
serBuf[serBufChars] = '\0';
+
// Need to parse message to determine behavior
// Need to clean this up
+ //need to do this outside the read byte ---
char msgList[8][32];
sprintf(msgList[STATUS_MSG], "WMsg STATUS");
sprintf(msgList[POSVEL_MSG], "WMsg POSVEL");
@@ -98,16 +134,19 @@
sprintf(msgList[STOPSTREAM_MSG], "WMsg POSSTREAM N");
sprintf(msgList[STARTLOGINFO_MSG], "WMsg LOGINFO Y");
sprintf(msgList[STOPLOGINFO_MSG], "WMsg LOGINFO N");
+ //message length is from 10 to 16 chars
+
// assume an invalid message which needs to be reset
bool validMessage = false;
bool resetMessage = true;
+
// Check for valid message
- for (int m = 0; m < 8 && !validMessage; m++)
+ for (int m = 0; m < 8 && !validMessage; m++) //check for all messages ...
{
if (strncmp(serBuf, msgList[m], serBufChars) == 0)
{
validMessage = true;
- // buffer length is same as message length
+ //test that chars in the serial buffer is same as message length
if (serBufChars == strlen(msgList[m]))
{
switch(m)
@@ -143,6 +182,7 @@
}
}
}
+
// if message should be reset
if (resetMessage)
{
@@ -154,7 +194,7 @@
{
// start a new message
serBuf[serBufChars++] = inChar;
- serBuf[serBufChars] == '\0';
+ serBuf[serBufChars] = '\0';
}
// Append end of string character
serBuf[serBufChars] = '\0';
@@ -164,6 +204,10 @@
void sendASCII(char* ASCI_message, int numChars)
{
+ /////////////////////////////////////////////////
+ //send an ASCII command to the GPS receiver
+ /////////////////////////////////////////////////
+
//char ASCI_message[] = "unlogall COM1";
int as = numChars - 1;
unsigned char CR = 0x0d; //ASCII Carriage Return
@@ -195,7 +239,7 @@
//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 lauinch the GPS receiver
+ //just wait to launch the GPS receiver
for (int i=0; i<5; i++) { toPC.printf(" to start: %3d \n", 4-i); wait(1); }
@@ -210,29 +254,36 @@
else
toPC.printf(" opened the IMUGPS data file \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 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 CDU can be used in parallel
+ //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 921600 n 8 1 n off";
+ char ch2[] = "serialconfig COM1 460800 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
+ //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("set serial config \n");
@@ -259,7 +310,8 @@
//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(921600); wait_ms(500); //without this wait -- the baud rate is not detected when using MODSERIAL
+ GPS_COM1.baud(460800); 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
};
void setupTriggers()
@@ -274,8 +326,8 @@
int test = 0;
unsigned short messageCounter = 0;
unsigned short savedMessageCounter = 0;
-unsigned char msgBuffer[1536];
-unsigned short messageLocation[6] = {0};
+unsigned char msgBuffer[1536]; //array to contain one full second of GPS bytes
+unsigned short messageLocation[6] = {0}; //stores the message location start within the message buffer
//see the mbed COOKBOOK for MODSERIAL
//MODSERIAL is an easy to use library that extends Serial to add fully buffered input and output.
@@ -296,19 +348,41 @@
perSecMessageCounter++;
messageDetected = true;
}
+ //byteCounter reset to zero in main after the 1PPS is detected -- its NOT reset in the 1PPS ISR
byteCounter++; //total per-sec byte counter (reset to zero in main when 1PPS detected)
};
+void earthCoefficients(double latitudeRad, double longitudeRad, double height, double &latRateFac, double &lonRateFac)
+{
+ //compute the lat and lon factors for use in the interpolation of the lat and lon between 1 sec epochs
+ //see this document (page 32) www.fas.org/spp/military/program/nav/basicnav.pdf
+ double eccen = 0.0818191908426; //WGS84 earth eccentricity
+ double earthRadius = 6378137; //WGS84 earthRadius in meters
+ double eccenSinLat = eccen * sin(latitudeRad);
+ double temp1 = 1.0 - eccenSinLat*eccenSinLat;
+ double temp2 = sqrt(temp1);
+ double r_meridian = earthRadius * ( 1.0 - eccen*eccen)/ (temp1 * temp2);
+ double r_normal = earthRadius / temp2;
+
+ //multiply latRateFac times V-north to get the latitude rate in radians [er sec
+ latRateFac = 1.0 / (r_meridian + height);
+
+ //multiply lonRatFac by VEast to get the longitude rate in radians per sec
+ lonRateFac = 1.0 / ( (r_normal + height) * cos(latitudeRad) );
+}
+
int main() {
//FILE *fpIMU = NULL;
//FILE *fpGPS = NULL;
FILE *fpNav = NULL;
- OEM615BESTPOS posMsg;
- OEM615BESTPOS curPos;
- OEM615BESTVEL velMsg;
- OEM615BESTVEL curVel;
+
+ OEM615BESTPOS posMsg; //BESTPOS structure in OEMV615.h
+ OEM615BESTPOS curPos; //BESTPOS structure in OEMV615.h
+ OEM615BESTVEL velMsg; //BESTVEL structure in OEMV615.h
+ OEM615BESTVEL curVel; //BESTVEL structure in OEMV615.h
+
int msgLen;
int msgEnd;
@@ -320,45 +394,62 @@
//setup Hotshoe
setupTriggers();
+
//attempt to use the mbed RTOS library
//Thread thread(writeThread);
+ //this doesnt show up on the PC Rich Text Box because we dont start the init til after this occurs
toPC.printf("completed setting up COM ports \n");
- //set up the interrupt to catch the serial byte availability
+ //set up the interrupt to catch the GPS receiver serial bytes as they are presented
GPS_COM1.attach(&readSerialByte, MODSERIAL::RxIrq);
- timeFromPPS.start();
+ timeFromPPS.start(); //start the time for measuring time from 1PPS events
- //while(PPSCounter < 1000)
- while(1)
+ while(PPSCounter < 100)
+ ///////////////////////////////////////////////////////////////////////////
+ // top of the while loop
+ ///////////////////////////////////////////////////////////////////////////
+ //while(1)
{
//read the USB serial data from the PC to check for commands
+ //in the primary real-time portion, there are no bytes from the PC so this has no impact
readFromPC();
- if (sendPosVel)
+ //we should put the below stuff into the readPC() procedure.
+ //only do these actions in response to a command so no need for the tests w/o an inoput byte from the PC
+ //perform the activities as a response to the commands
+ if (sendPosVel) //true if we want to return a position solution
{
- sendPosVel=false;
+ sendPosVel=false; //set to true if a POSVEL is requested from the PC
char solReady = 'N';
- if (posMsg.solStatus == 0)
+ if (posMsg.solStatus == 0) //how is this set??
{
solReady = 'Y';
}
+
+ //north and east velocity from the horizontal speed and heading
+ //velMsg may not be the "current" message --- but is the one also associated with a position message
double nVel = velMsg.horizontalSpeed*cos(velMsg.heading*DEGREES_TO_RADIANS);
double eVel = velMsg.horizontalSpeed*sin(velMsg.heading*DEGREES_TO_RADIANS);
+
// For the 1 second deltas with which we are dealing
- // this calculation should be close enough for now
- // approximately 1 nautical mile / minute latitude, 60 minutes/degree, 1852 meters/nautical mile
+ // This calculation should be close enough for now
+ // Approximately 1 nautical mile / minute latitude, 60 minutes/degree, 1852 meters/nautical mile
double latMetersPerDeg = 60.0*1852.0;
// longitude separation is approximately equal to latitude separation * cosine of latitude
double lonMetersPerDeg = latMetersPerDeg*cos(posMsg.latitude*DEGREES_TO_RADIANS);
// Elapsed time since last known GPS position
+ //PPSTimeOffset is a result of possibly missing a prior GPS position message
+ // timeFromPPS.read() is always the time from the moset recent 1PPS
double elTime = (double)PPSTimeOffset + timeFromPPS.read();
- // Position time
+
+ // Position time -- GPSTime is the time of the last valid GPS position message
double posTime = GPSTime + elTime;
// Estimated position based on previous position and velocity
+ // posMsg is the last time when the BESTVEL and BESTPOS messages had identical times
double latPos = posMsg.latitude + (nVel/latMetersPerDeg)*elTime;
double lonPos = posMsg.longitude + (eVel/lonMetersPerDeg)*elTime;
double htPos = posMsg.height + velMsg.verticalSpeed/(60*1852)*elTime;
@@ -374,7 +465,9 @@
velMsg.verticalSpeed
);
}
- if (sendStatus)
+
+ //all this does is assess the GPS convergence -- really available in the above
+ if (sendStatus) //send the status message to the PC
{
sendStatus=false;
char solReady = 'N';
@@ -387,7 +480,9 @@
solReady
);
}
- if (sendRecData)
+
+ //should just record ALL the data -- can pck over it in the post-processing
+ if (sendRecData) //begin to (or stop) record the serial data
{
sendRecData=false;
char recChar = 'N';
@@ -427,8 +522,11 @@
recChar
);
}
- recordDataled = recordData;
- if (sendStreamPos)
+
+ //this is called everytime through the loop -- wasteful
+ //recordDataled = recordData;
+
+ if (sendStreamPos) //stream the position data to the PC
{
sendStreamPos=false;
char streamChar = 'N';
@@ -440,7 +538,9 @@
streamChar
);
}
- if (sendLogMsgInfo)
+
+ //not sure this is ever used ..
+ if (sendLogMsgInfo) //send log info to the PC
{
sendLogMsgInfo=false;
char logChar = 'N';
@@ -452,95 +552,32 @@
logChar
);
}
- if (IMUDataReady)
- {
- //write the IMU data
- //if (recordData && (fpIMU != NULL))
- if (recordData && (fpNav != NULL))
+
+
+ ////////////////////////////////////////////////////////////////////////////
+ //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 thi loop
+ /////////////////////////////////////////////////////////////////////////////
+ if (!IMUDataReady && lookingForMessages && (timeFromPPS.read_us() > 20000)) //it takes less than 20msec to receive all messages
+ {
+ toPC.printf(" num messages = %3d time = %5d \n", perSecMessageCounter, timeFromPPS.read_us());
+
+ //cycle through all the bytes stored this sec (after the 1PPS as set)
+ // perSecMessageCounter is incremented whenever we detect a new message headet 0xAA44121C sequence
+ for (int i=0; i<perSecMessageCounter; i++)
{
- fwrite(imuRec.dataWord, sizeof(IMUREC), 1, fpNav);
- }
- IMUDataReady = false;
- }
- //if (lookingForMessages && (timeFromPPS.read() > 0.100)) //it takes less than 20msec to receive all messages
- {
-
- //toPC.printf(" num messages = %3d time = %5d \n", perSecMessageCounter, timeFromPPS.read_us());
- for (int i=0; i<perSecMessageCounter; i++)
- {
- // ensure at message header has arrived before processing
- if (byteCounter < (messageLocation[i] + sizeof(MESSAGEHEADER)))
+ msgHeader[i] = (MESSAGEHEADER*)&msgBuffer[messageLocation[i]];
+ toPC.printf("WMsg MESSAGEINFO %5d %5d \n",
+ msgHeader[i]->messageID,
+ messageLocation[i]);
+ //test for a message 42 (BESTPOS)
+ if (msgHeader[i]->messageID == 42)
{
- // Complete message header has not been received.
- // Clear processed messages and break out of message processing loop
- for (int j = 0; j < i; j++)
- {
- messageLocation[j] = messageLocation[i+j];
- perSecMessageCounter--;
- }
- break;
- }
- msgHeader[i] = (MESSAGEHEADER*)&msgBuffer[messageLocation[i]];
- // Ensure complete message has been received
- // Message length is header length + message length + CRC
- msgLen = 28;
- switch (msgHeader[i]->messageID)
- {
- case 42:
- msgLen = 104;
- break;
- case 99:
- msgLen = 76;
- break;
- default:
- msgLen = msgHeader[i]->headerLength + msgHeader[i]->messageLength + sizeof(unsigned long);
- break;
+ curPos = *((OEM615BESTPOS*)&msgBuffer[messageLocation[i]]);
- }
- msgLen = msgHeader[i]->headerLength + msgHeader[i]->messageLength + sizeof(unsigned long);
- // Find last byte position of message
- msgEnd = messageLocation[i] + msgLen;
- if (byteCounter < msgEnd)
- {
- // Complete message has not been received.
- // Clear processed messages and break out of message processing loop
- for (int j = 0; j < i; j++)
+ if (streamPos)
{
- messageLocation[j] = messageLocation[i+j];
- perSecMessageCounter--;
- }
- break;
- }
- else if ((i < (perSecMessageCounter-1)) &&
- (messageLocation[i+i] < msgEnd)) // ignore CRC for now
- {
- // Next message was started before this mesage was completely received.
- // Ignore and continue on to the next message
- continue;
- }
- if (logMsgInfo)
- {
- toPC.printf("WMsg MESSAGEINFO %5d %5d %5d %5d %5d = %5d (%5d)\n",
- msgHeader[i]->messageID,
- messageLocation[i],
- msgHeader[i]->headerLength,
- msgHeader[i]->messageLength,
- sizeof(unsigned long),
- msgEnd,
- byteCounter);
- }
- //toPC.printf(" %5d ", msgHeader[i]->messageID);
- if ((msgHeader[i]->messageID == 42) ||
- (msgHeader[i]->messageID == 99))
- {
- if (msgHeader[i]->messageID == 42)
- {
- // Wait until velocity message has also been received before using as
- // base position
- //memcpy(&curPos, &msgBuffer[messageLocation[i]], sizeof(OEM615BESTPOS));
- curPos = *((OEM615BESTPOS*)&msgBuffer[messageLocation[i]]);
- if (streamPos)
- {
toPC.printf("WMsg BESTPOS %d %d %d %8.5lf %9.5lf %5.3lf %5.3f %5.3f %5.3f %5.3f %5.3f %5.3f %d %d %d %d %d\n",
curPos.msgHeader.GPSTime_msecs,
curPos.solStatus,
@@ -559,69 +596,86 @@
curPos.numGGL1,
curPos.extSolStatus,
curPos.sigMask);
- }
- }
- else if (msgHeader[i]->messageID == 99)
- {
- // Wait until position message has also been received before using as
- // base position
- //memcpy(&curVel, &msgBuffer[messageLocation[i]], sizeof(OEM615BESTVEL));
- curVel = *((OEM615BESTVEL*)&msgBuffer[messageLocation[i]]);
- }
- if ((curVel.msgHeader.GPSTime_msecs+250)/1000 ==
- (curPos.msgHeader.GPSTime_msecs+250)/1000)
- {
- // update position and velocity used for calculation
- GPSTimemsecs = curPos.msgHeader.GPSTime_msecs;
- GPSTime = (double)GPSTimemsecs/1000.0;
- velMsg = curVel;
- posMsg = curPos;
- PPSTimeOffset = 0;
}
}
- if (i == (perSecMessageCounter-1))
+
+ //check for a message 99 (BESTVEL) -- and cast it into its message structure
+ else if (msgHeader[i]->messageID == 99)
+ {
+ curVel = *((OEM615BESTVEL*)&msgBuffer[messageLocation[i]]);
+ }
+
+ //the below test ensures that the positin and veocity are matched in time
+ //not sure the reason for the "250" below
+ if ((curVel.msgHeader.GPSTime_msecs+250)/1000 ==
+ (curPos.msgHeader.GPSTime_msecs+250)/1000)
{
- if (recordData && (fpNav != NULL))
- {
- fwrite(msgBuffer, byteCounter, 1, fpNav);
- }
- byteCounter = 0;
- perSecMessageCounter = 0;
+ // update position and velocity used for calculation
+ GPSTimemsecs = curPos.msgHeader.GPSTime_msecs;
+ GPSTime = (double)GPSTimemsecs/1000.0;
+ velMsg = curVel; //
+ posMsg = curPos;
+
+ /////////////////////////////////////////////////////////////////////////////////////////
+ //IMPORTANT: we reset the PPSTimeOffset when we have a matching position and velocity
+ PPSTimeOffset = 0;
+ /////////////////////////////////////////////////////////////////////////////////////////
}
- }
- //toPC.printf(" %3d %8d \n", msgHeader[0]->timeStatus, GPSTimemsecs);
- //if (recordData && (fpGPS != NULL))
-
- /*
+ }
+ lookingForMessages = false;
+
+ } //end of the GPS message processing
+
+ //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
+ {
+ imuRec.GPSTime = GPSTimemsecs + timeFromPPS.read_us()/1000000.0;
+ spi.write((int) HIGH_REGISTER[0]); // next read will return results from HIGH_REGITER[0]
+ for (int i=0; i<6; i++) //read the 6 rate and accel variables
+ {
+ wd.pt[1] = (unsigned short)spi.write((int) LOW_REGISTER[i]) ;
+ if (i<5) // dont this on the last because this was pre-called
+ { wd.pt[0] = (unsigned short)spi.write((int) HIGH_REGISTER[i+1]); }
+ imuRec.dataWord[i] = wd.dataWord; //data word is a signed long
+
+ }
+ IMURecordCounter++;
+ //write the IMU data
+ //if (recordData && (fpIMU != NULL))
if (recordData && (fpNav != NULL))
{
- fwrite(msgBuffer, byteCounter, 1, fpNav);
+ IMUbytesWritten += fwrite(imuRec.dataWord, sizeof(IMUREC), 1, fpNav);
}
- */
- //lookingForMessages = false;
+ IMUClockCounter++;
+ IMUDataReady = false;
}
- if (messageDetected)
+
+ if (messageDetected) //some GPS message header has been detected
{
- //toPC.printf(" msgTime = %4d \n", timeFromPPS.read_us());
+ toPC.printf(" msgTime = %4d \n", timeFromPPS.read_us());
messageDetected = false;
}
- if (camera1EventDetected)
+
+ if (camera1EventDetected) //we have detected a camera trigger event
{
toPC.printf("WMsg TRIGGERTIME %5.3lf\n", camera1Time);
camera1EventDetected = false;
}
- if (detectedGPS1PPS)
+
+ if (detectedGPS1PPS) //true if we are exactly at a 1PPS event detection
{
- //toPC.printf(" PPSCounter = %4d byteCounter = %10d num Messages Received = %3d IMUClock = %4d\n",
- // PPSCounter, byteCounter, perSecMessageCounter, savedIMUClockCounter);
+ toPC.printf(" PPSCounter=%4d byteCounter=%10d Msgs Received=%3d IMUClock=%4d bytesWritten=%8d\n",
+ PPSCounter, savedByteCounter, savedPerSecMessageCounter, savedIMUClockCounter, IMUbytesWritten);
if (recordData && (fpNav != NULL) && (byteCounter > 0))
{
- fwrite(msgBuffer, byteCounter, 1, fpNav);
+ // we know that we are not reading a GPS message at exactly the 1PPS occurrence
+ fwrite(msgBuffer, byteCounter, 1, fpNav); // this writes out a complete set of messages for ths sec
}
- byteCounter = 0;
- perSecMessageCounter=0;
detectedGPS1PPS = false;
}
}
+
+ fclose(fpNav);
toPC.printf(" normal termination \n");
}
\ No newline at end of file