james kain
JEK changes enabling proper recording of IMU/GPS datastrams - 02-APR-2013
Fork of
GPS_Incremental
by 
Dan Matthews
Revision 6:2a8486283198, committed 2013-04-02
- Comitter:
- jekain314
- Date:
- Tue Apr 02 15:22:37 2013 +0000
- Parent:
- 5:46903325b61f
- Child:
- 7:2e20e4cf53e6
- Commit message:
- JEK changes enabling proper recording of IMU/GPS datastreams to the SD-card
Changed in this revision
--- a/ADIS16488.h Fri Mar 29 20:52:54 2013 +0000
+++ b/ADIS16488.h Tue Apr 02 15:22:37 2013 +0000
@@ -22,13 +22,12 @@
struct IMUREC
{
unsigned long synch;
- unsigned char msgID;
- double GPSTime;
+ unsigned short msgID;
+ unsigned long GPSTime;
long dataWord[6];
+ // 4 + 2 + 4 + 24 = 34
} imuRec;
-
-
void IMUDataReadyISR(void)
{
IMUDataReady = true;
@@ -40,7 +39,6 @@
ADIS_DR.mode(PullDown);
ADIS_RST = 0;
- printf("\nStart of ADIS test\n");
// set the IMU dataReady ISR
ADIS_DR.rise(&IMUDataReadyISR);
@@ -71,7 +69,13 @@
//change the page to 0 to get the data
spi.write((int)0x8000); //change to page 0
+ toPC.printf(" setting the default values\n");
+
//set the IMU synch and message ID
- imuRec.synch = 0xAA44121C; //same as the GPS synch words
+ imuRec.synch = 0x1C1244AA; //same as the GPS synch words
+
imuRec.msgID=111; //IMU record ID
+
+ toPC.printf(" finished setting the default values\n");
+
}
--- a/OEM615.h Fri Mar 29 20:52:54 2013 +0000
+++ b/OEM615.h Tue Apr 02 15:22:37 2013 +0000
@@ -40,6 +40,26 @@
unsigned long CRC;
};
+/* Solution Status descritpion from OEMV manual
+0 SOL_COMPUTED Solution computed
+1 INSUFFICIENT_OBS Insufficient observations
+2 NO_CONVERGENCE No convergence
+3 SINGULARITY Singularity at parameters matrix
+4 COV_TRACE Covariance trace exceeds maximum (trace > 1000 m)
+5 TEST_DIST Test distance exceeded (maximum of 3 rejections if distance >10 km)
+6 COLD_START Not yet converged from cold start
+7 V_H_LIMIT Height or velocity limits exceeded
+8 VARIANCE Variance exceeds limits
+9 RESIDUALS Residuals are too large
+10 DELTA_POS Delta position is too large
+11 NEGATIVE_VAR Negative variance
+12 Reserved
+13 INTEGRITY_WARNING Large residuals make position unreliable
+18 PENDING
+19 INVALID_FIX The fixed position, entered using the FIX POSITION command, is not valid
+20 UNAUTHORIZED Position type is unauthorized - HP or XP
+*/
+
#pragma pack(1)
//structure for BESTPOS message
struct OEM615BESTPOS
@@ -72,6 +92,26 @@
unsigned long CRC;
};
+//GPS-specific pins
+DigitalOut GPS_Reset(p18); //GPS RESET line
+InterruptIn PPSInt(p15); // GPS 1PPS (timemark) from the OEM615
+InterruptIn IMUClock(p17);
+
+Timer timeFromPPS;
+unsigned long GPSTimemsecs = 0;
+double GPSTime = 0;
+int PPSTimeOffset = 0;
+
+//mbed tx/rx interface to the GPS COM1 port
+MODSERIAL GPS_COM1(p9,p10); //this serial port communicates with the GPS receiver serial port (COM1)
+
+int test = 0;
+unsigned short messageCounter = 0;
+unsigned short savedMessageCounter = 0;
+const unsigned short maxGPSbytesPerSec = 1536;
+unsigned char msgBuffer[maxGPSbytesPerSec]; //array to contain one full second of GPS bytes
+const unsigned char maxGPSMessagesPerSec = 12;
+unsigned short messageLocation[maxGPSMessagesPerSec] = {0}; //stores the message location start within the message buffer
//this code was taken from the Novatel Firmware document page 35
#define CRC32_POLYNOMIAL 0xEDB88320L
@@ -113,18 +153,54 @@
return( ulCRC );
}
-//GPS-specific pins
-DigitalOut GPS_Reset(p18); //GPS RESET line
-InterruptIn PPSInt(p15); // GPS 1PPS (timemark) from the OEM615
-InterruptIn IMUClock(p17);
+
+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
+ unsigned char LF = 0x0a; //ASCII Line Feed
+
+ //printf("%s", ch);
+ //printf("\n");
+
+ for (int i=0; i<as; i++) GPS_COM1.putc(ASCI_message[i]);
+ GPS_COM1.putc(CR); //carriage return at end
+ GPS_COM1.putc(LF); //line feed at end
+};
+
-Timer timeFromPPS;
-unsigned long GPSTimemsecs = 0;
-double GPSTime = 0;
-int PPSTimeOffset = 0;
+//see the mbed COOKBOOK for MODSERIAL
+//MODSERIAL is an easy to use library that extends Serial to add fully buffered input and output.
+void readSerialByte(MODSERIAL_IRQ_INFO *q)
+{
+ MODSERIAL *serial = q->serial;
+ unsigned char synch0 = serial->getc();
+ msgBuffer[byteCounter % maxGPSbytesPerSec] = synch0;
-//mbed tx/rx interface to the GPS COM1 port
-MODSERIAL GPS_COM1(p9,p10); //this serial port communicates with the GPS receiver serial port (COM1)
+ //we need to trap the GPS message header byte-string 0xAA44121C
+ //generate a 4-byte sliding-window sequence from the input bytes
+ //shift last 4-byte value left 8 bits & push recently read byte (synch0) into low-order byte
+ test = (test<<8) | synch0; //
+
+ if (test == 0xAA44121C) //test for the Receiver message header signature
+ {
+ messageLocation[perSecMessageCounter % maxGPSMessagesPerSec] = byteCounter-3; //store the location of this message (with 4 synch words)
+ 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)
+
+};
+
+
+
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/PCMessaging.h Tue Apr 02 15:22:37 2013 +0000
@@ -0,0 +1,293 @@
+//these are defines for the messages that are sent from the PC across the USB
+//these messages produce reactions on the mbed
+const unsigned char STATUS_MSG =0;
+const unsigned char POSVEL_MSG =1;
+const unsigned char STARTDATA_MSG =2;
+const unsigned char STOPDATA_MSG =3;
+const unsigned char STARTSTREAM_MSG =4;
+const unsigned char STOPSTREAM_MSG =5;
+const unsigned char STARTLOGINFO_MSG =6;
+const unsigned char STOPLOGINFO_MSG =7;
+
+const double DEGREES_TO_RADIANS = acos(-1.0)/180.0;
+const double eccen = 0.0818191908426; //WGS84 earth eccentricity
+const double earthRadius = 6378137; //WGS84 earthRadius in meters
+
+char serBuf[128];
+int serBufChars=0;
+
+//flags to control the PC command actions
+bool sendPosVel =false;
+bool sendStatus =false;
+bool sendRecData =false;
+bool streamPos =false;
+bool sendStreamPos =false;
+bool logMsgInfo =false;
+bool sendLogMsgInfo =false;
+bool recordData =false;
+
+
+const unsigned char numMessages = 8; //number of potential messages
+char msgList[numMessages][32]; //text array storing the command messages from the PC
+char minMessageSize = 10; //minimum size of a text message
+unsigned char CR = 0x0d; //ASCII Carriage Return
+unsigned char LF = 0x0a; //ASCII Line Feed
+
+void setUpMessages(void)
+{
+ //set up the ASCII text records that are candidates to be passed from the PC
+ sprintf(msgList[STATUS_MSG], "WMsg STATUS");
+ sprintf(msgList[POSVEL_MSG], "WMsg POSVEL");
+ sprintf(msgList[STARTDATA_MSG], "WMsg RECORDDATA Y");
+ sprintf(msgList[STOPDATA_MSG], "WMsg RECORDDATA N");
+ sprintf(msgList[STARTSTREAM_MSG], "WMsg POSSTREAM Y");
+ 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
+
+ toPC.printf(" finished setting up messages \n");
+}
+
+void readFromPC()
+{
+ //The received commands only 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(); //read char from the USB serial link to the PC
+
+ //incoming messages will end witb a CR / LF -- disregard these chars
+ if (inChar == CR || inChar == LF) return;
+
+ serBuf[serBufChars++] = inChar; //set this char in a char array
+
+ //no need to continue if numChars are less than the shortest candidate message
+ if (serBufChars < minMessageSize) return;
+
+ // Append end of string
+ //We always assume we have a complete message string and test for this below
+ serBuf[serBufChars] = '\0';
+
+ bool validMessage = false;
+
+ // Check for valid message -- there are numMessages possible messages
+ for (int m = 0; m < numMessages && !validMessage; m++) //check for all messages ...
+ {
+ //toPC.printf(" \n\n found chars to test %3d %3d %s \n\n\n ", serBufChars, strlen(msgList[m]), serBuf );
+
+ //check the current partial message against ALL possible messages
+ //messages must match in both strength length and text
+ if (serBufChars == strlen(msgList[m]) && strncmp(serBuf, msgList[m], serBufChars) == 0 )
+ {
+
+ //toPC.printf( "\n found valid message \n\n");
+
+ validMessage = true;
+ serBufChars = 0; //reset the character count to reset for next message
+
+ //set programmatic action flags based on the message
+ switch(m)
+ {
+ case STATUS_MSG:
+ sendStatus = true; //send a status message back to PC
+ break;
+ case POSVEL_MSG:
+ sendPosVel = true; //send a posvel message back to PC
+ break;
+ case STARTDATA_MSG: //start the data recording to the SD card
+ recordData = true;
+ sendRecData = true;
+ break;
+ case STOPDATA_MSG: //stop the data recording to the SD card
+ recordData = false;
+ sendRecData = true;
+ break;
+ case STARTSTREAM_MSG:
+ case STOPSTREAM_MSG:
+ streamPos = (m == STARTSTREAM_MSG);
+ sendStreamPos = true;
+ break;
+ case STARTLOGINFO_MSG:
+ case STOPLOGINFO_MSG:
+ logMsgInfo = (m == STARTLOGINFO_MSG);
+ sendLogMsgInfo = true;
+ break;
+ } //end Switch statement
+ break;
+ } //end test for a valid message
+ } //end message text loop
+ } //end pc.readable
+};
+
+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
+ //latRateFac & lonRateFac multiplied by Vnorth or VEast to get latRate and lonRate
+ //see this document (page 32) www.fas.org/spp/military/program/nav/basicnav.pdf
+
+ 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;
+
+ //divide Vnorth by latRateFac to get the latitude rate in deg per sec
+ latRateFac = (r_meridian + height)* DEGREES_TO_RADIANS;
+
+ //divide VEast by lonRateFac to get the longitude rate in deg per sec
+ lonRateFac = (r_normal + height) * cos(latitudeRad)* DEGREES_TO_RADIANS;
+}
+
+void sendPosVelMessageToPC(OEM615BESTPOS posMsg, OEM615BESTVEL velMsg)
+{
+ //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);
+
+ double latRateFac;
+ double lonRateFac;
+
+ earthCoefficients( posMsg.latitude*DEGREES_TO_RADIANS,
+ posMsg.longitude*DEGREES_TO_RADIANS,
+ posMsg.height,
+ latRateFac, lonRateFac);
+
+ //commented calculations are for a spherical earth (Chris's original computation)
+ // 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
+ //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 -- GPSTime is the time of the last valid GPS position message
+ double posTime = GPSTime + elTime;
+
+ //toPC.printf(" elTime = %6.3f PPSimeOffset = %6.3f \n", elTime, PPSTimeOffset);
+ //toPC.printf(" latRateFac = %10.3f lonRateFac = %10.3f \n", latRateFac, lonRateFac);
+ //toPC.printf(" latRateFac = %10.3f lonRateFac = %10.3f \n", latMetersPerDeg, lonMetersPerDeg);
+
+ // 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 latPos = posMsg.latitude + (nVel/latRateFac)*elTime;
+ double lonPos = posMsg.longitude + (eVel/lonRateFac)*elTime;
+ double htPos = posMsg.height + velMsg.verticalSpeed/(60*1852)*elTime;
+
+ toPC.printf("WMsg POSVEL %5.3lf %1d %s %8.5lf %9.5lf %4.3lf %4.3lf %4.3lf %4.3lf\n",
+ posTime,
+ posMsg.numSolSV,
+ posMsg.solStatus,
+ latPos,
+ lonPos,
+ htPos,
+ nVel,
+ eVel,
+ velMsg.verticalSpeed
+ );
+}
+
+void processPCmessages(FILE* &fpNav, OEM615BESTPOS posMsg, OEM615BESTVEL velMsg)
+{
+
+ //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; //set to true if a POSVEL is requested from the PC
+ sendPosVelMessageToPC(posMsg, velMsg);
+ }
+
+ //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';
+ //solStatus
+ if (posMsg.solStatus == 0) //see description of solution status in OEMV615.h
+ {
+ solReady = 'Y';
+ }
+ toPC.printf("WMsg STATUS %5.3lf %c\n",
+ GPSTime,
+ solReady
+ );
+ }
+
+ //should just record ALL the data -- can pick over it in the post-processing
+ if (sendRecData) //begin to (or stop) record the serial data
+ {
+ sendRecData=false;
+ char recChar = 'N';
+ if (recordData)
+ {
+ if ((fpNav == NULL))
+ {
+ fpNav = fopen("/sd/Data/NAV.bin", "wb");
+ //toPC.printf("\n opened the SD card file recordData=%10d \n\n", fpNav);
+ }
+ if (fpNav != NULL)
+ {
+ recChar = 'Y';
+ }
+ else
+ {
+ toPC.printf(" Could not open the SD card \n\n");
+ }
+ }
+ else
+ {
+ if (fpNav != NULL)
+ {
+ toPC.printf(" closing the SD card file \n\n");
+ fclose(fpNav);
+ recordData = false;
+ fpNav = NULL;
+ }
+ }
+ toPC.printf("WMsg RECORDDATA %c\n",
+ recChar
+ );
+ }
+
+ if (sendStreamPos) //stream the position data to the PC
+ {
+ sendStreamPos=false;
+ char streamChar = 'N';
+ if (streamPos)
+ {
+ streamChar = 'Y';
+ }
+ toPC.printf("WMsg POSSTREAM %c\n",
+ streamChar
+ );
+ }
+
+ //not sure this is ever used ..
+ if (sendLogMsgInfo) //send log info to the PC
+ {
+ sendLogMsgInfo=false;
+ char logChar = 'N';
+ if (logMsgInfo)
+ {
+ logChar = 'Y';
+ }
+ toPC.printf("WMsg LOGINFO %c\n",
+ logChar
+ );
+ }
+
+
+}
--- a/main.cpp Fri Mar 29 20:52:54 2013 +0000
+++ b/main.cpp Tue Apr 02 15:22:37 2013 +0000
@@ -1,227 +1,84 @@
#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
-//#include "rtos.h"
-#include "OEM615.h"
-
-#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
-#define STOPDATA_MSG 3
-#define STARTSTREAM_MSG 4
-#define STOPSTREAM_MSG 5
-#define STARTLOGINFO_MSG 6
-#define STOPLOGINFO_MSG 7
-
-#define DEGREES_TO_RADIANS (3.14519/180.0)
//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); //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
+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 recordDataled(LED4); //set the led when the record is on
+InterruptIn camera1Int(p30); // camera interrupt in
+DigitalOut camera2Pin(p29); // We dont 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
+Serial toPC(USBTX, USBRX); //connect the GPS TX, RX to p9 and p10
-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??
+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 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;
+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
+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 IMUClockCounter = 0; //counter for IMU samples per sec
+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
-//flags to control the PC command actions
-bool sendPosVel=false;
-bool sendStatus=false;
-bool sendRecData=false;
-bool streamPos=false;
-bool sendStreamPos=false;
-bool logMsgInfo=false;
-bool sendLogMsgInfo=false;
+//////////////////////////////////////////////////////////////////////
+// the below should become classes
+//////////////////////////////////////////////////////////////////////
+#include "OEM615.h" //OEM615 GPS activities
+#include "ADIS16488.h" //ADIS16488 activities
+#include "PCMessaging.h" //PC messaging activities
//ISR for detection of the GPS 1PPS
void detect1PPSISR(void)
{
- timeFromPPS.reset(); //reset the 1PPS timer upon 1PPS detection
+ 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;
+ savedByteCounter = byteCounter; //save byteCounter for display in main
+ savedPerSecMessageCounter = perSecMessageCounter; //save for display un main
+ IMUClockCounter = 0; //counts per-sec IMU samples (between 1PPS events)
+ 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; //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
+ detectedGPS1PPS = true; //set false in the main when 1PPS actions are complete
+ lookingForMessages = true; //set false in main after processing messages
+ PPSCounter++; //count number of 1PPS epoch
+
+ //note -- the below accounts for time information becoming available AFTER the 1PPS event
+ PPSTimeOffset++; //counts 1PPS events between 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();
-
+ //GPSTime is from POS message header
+ //PPSTimeOffset is an even sec to account for Time becoming known AFTER the 1PPS
+ //PPSTimeOffset + timeFromPPS.read() can be as large as 1.02 secs
+ camera1Time = GPSTime + PPSTimeOffset + timeFromPPS.read();
+ camera1EventDetected = true; //reset to false in main after processing the image detection
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");
- sprintf(msgList[STARTDATA_MSG], "WMsg RECORDDATA Y");
- sprintf(msgList[STOPDATA_MSG], "WMsg RECORDDATA N");
- sprintf(msgList[STARTSTREAM_MSG], "WMsg POSSTREAM Y");
- 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++) //check for all messages ...
- {
- if (strncmp(serBuf, msgList[m], serBufChars) == 0)
- {
- validMessage = true;
- //test that chars in the serial buffer is same as message length
- if (serBufChars == strlen(msgList[m]))
- {
- switch(m)
- {
- case STATUS_MSG:
- sendStatus = true;
- break;
- case POSVEL_MSG:
- sendPosVel = true;
- break;
- case STARTDATA_MSG:
- case STOPDATA_MSG:
- recordData = (m == STARTDATA_MSG);
- sendRecData = true;
- break;
- case STARTSTREAM_MSG:
- case STOPSTREAM_MSG:
- streamPos = (m == STARTSTREAM_MSG);
- sendStreamPos = true;
- break;
- case STARTLOGINFO_MSG:
- case STOPLOGINFO_MSG:
- logMsgInfo = (m == STARTLOGINFO_MSG);
- sendLogMsgInfo = true;
- break;
-
- }
- }
- // message is still in progress, do not reset
- else
- {
- resetMessage = false;
- }
- }
- }
-
- // if message should be reset
- if (resetMessage)
- {
- // reset serial buffer character count
- serBufChars = 0;
- // if invalid message and most recent character is 'W' (first message character),
- // possible message collision
- if ((!validMessage) && (inChar == 'W'))
- {
- // start a new message
- serBuf[serBufChars++] = inChar;
- serBuf[serBufChars] = '\0';
- }
- // Append end of string character
- serBuf[serBufChars] = '\0';
- }
- }
-};
-
-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
- unsigned char LF = 0x0a; //ASCII Line Feed
-
- //printf("%s", ch);
- //printf("\n");
-
- for (int i=0; i<as; i++) GPS_COM1.putc(ASCI_message[i]);
- GPS_COM1.putc(CR); //carriage return at end
- GPS_COM1.putc(LF); //line feed at end
-};
-
-//FILE* fp = NULL;
+///////////////////////////////////////////////////////
+//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
@@ -242,18 +99,24 @@
//just wait to launch the GPS receiver
for (int i=0; i<5; i++) { toPC.printf(" to start: %3d \n", 4-i); wait(1); }
-
- mkdir("/sd/Data", 0777);
+ sd_detect.mode(PullUp);
- /*
- fp = fopen("/sd/Data/IMUGPS.bin", "wb");
- if (fp == NULL)
+ if (sd_detect == 0)
+ {
+ mkdir("/sd/Data", 0777);
+ }
+ else
+ {
+ toPC.printf(" SD card not present \n");
+ }
+
+ fpNav = fopen("/sd/Data/IMUGPS.bin", "wb");
+ if (fpNav == NULL)
{
toPC.printf(" cannot open the IMUGPS data file \n");
}
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
@@ -284,7 +147,7 @@
//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";
+ //char ch8[] = "FREQUENCYOUT enable 10000 1000000";
toPC.printf("set serial config \n");
sendASCII(ch7, sizeof(ch7)); wait_ms(500);
@@ -301,8 +164,8 @@
//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);
+ //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("set the COM ports to high rate\n");
@@ -323,68 +186,16 @@
};
-int test = 0;
-unsigned short messageCounter = 0;
-unsigned short savedMessageCounter = 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.
-void readSerialByte(MODSERIAL_IRQ_INFO *q)
-{
- MODSERIAL *serial = q->serial;
- unsigned char synch0 = serial->getc();
- msgBuffer[byteCounter] = synch0;
-
- //we need to trap the GPS message header byte-string 0xAA44121C
- //generate a 4-byte sliding-window sequence from the input bytes
- //shift last 4-byte value left 8 bits & push recently read byte (synch0) into low-order byte
- test = (test<<8) | synch0; //
-
- if (test == 0xAA44121C) //test for the Receiver message header signature
- {
- messageLocation[perSecMessageCounter] = byteCounter-3; //store the location of this message (with 4 synch words)
- 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;
+/////////////////////////////////////////////////////////////////////
+// mbed main to support the Waldo_FCS
+/////////////////////////////////////////////////////////////////////
+int main() {
- //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; //BESTPOS structure in OEMV615.h
+ //these are structures for the to GPS messages that must be parsed
+ 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
+ OEM615BESTVEL velMsg; //BESTVEL structure in OEMV615.h that has matching time to a BESTPOS message
OEM615BESTVEL curVel; //BESTVEL structure in OEMV615.h
-
- int msgLen;
- int msgEnd;
//set up the GPS and mbed COM ports
setupCOM();
@@ -394,166 +205,30 @@
//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");
+
+ setUpMessages(); //set up the expected text message commands frm the PC
//set up 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
-
- while(PPSCounter < 100)
+
+ toPC.printf("\n\n top of the main loop \n\n");
+
+ int totalBytesWritten = 0;
+
+ //while(PPSCounter < 100)
///////////////////////////////////////////////////////////////////////////
// top of the while loop
///////////////////////////////////////////////////////////////////////////
- //while(1)
+ 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();
-
- //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; //set to true if a POSVEL is requested from the PC
- char solReady = 'N';
- 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
- 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 -- GPSTime is the time of the last valid GPS position message
- double posTime = GPSTime + elTime;
+ processPCmessages(fpNav, posMsg, velMsg);
- // 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;
- toPC.printf("WMsg POSVEL %5.3lf %d %c %8.5lf %9.5lf %4.3lf %4.3lf %4.3lf %4.3lf\n",
- posTime,
- posMsg.numSolSV,
- solReady,
- latPos,
- lonPos,
- htPos,
- nVel,
- eVel,
- velMsg.verticalSpeed
- );
- }
-
- //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';
- if (posMsg.solStatus == 0)
- {
- solReady = 'Y';
- }
- toPC.printf("WMsg STATUS %5.3lf %c\n",
- GPSTime,
- solReady
- );
- }
-
- //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';
- if (recordData)
- {
- if ((fpNav == NULL))
- {
- fpNav = fopen("/sd/Data/NAV.bin", "wb");
- }
- if (fpNav != NULL)
- {
- recChar = 'Y';
- }
- //recChar = 'Y';
- }
- else
- {
- if (fpNav != NULL)
- {
- fclose(fpNav);
- fpNav = NULL;
- }
- /*
- if (fpIMU != NULL)
- {
- fclose(fpIMU);
- fpIMU = NULL;
- }
- if (fpGPS != NULL)
- {
- fclose(fpGPS);
- fpGPS = NULL;
- }
- */
- }
- toPC.printf("WMsg RECORDDATA %c\n",
- recChar
- );
- }
-
- //this is called everytime through the loop -- wasteful
- //recordDataled = recordData;
-
- if (sendStreamPos) //stream the position data to the PC
- {
- sendStreamPos=false;
- char streamChar = 'N';
- if (streamPos)
- {
- streamChar = 'Y';
- }
- toPC.printf("WMsg POSSTREAM %c\n",
- streamChar
- );
- }
-
- //not sure this is ever used ..
- if (sendLogMsgInfo) //send log info to the PC
- {
- sendLogMsgInfo=false;
- char logChar = 'N';
- if (logMsgInfo)
- {
- logChar = 'Y';
- }
- toPC.printf("WMsg LOGINFO %c\n",
- logChar
- );
- }
-
-
+//
////////////////////////////////////////////////////////////////////////////
//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
@@ -561,16 +236,29 @@
/////////////////////////////////////////////////////////////////////////////
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());
+ //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++)
{
- msgHeader[i] = (MESSAGEHEADER*)&msgBuffer[messageLocation[i]];
- toPC.printf("WMsg MESSAGEINFO %5d %5d \n",
- msgHeader[i]->messageID,
- messageLocation[i]);
+ msgHeader[i] = (MESSAGEHEADER*)&msgBuffer[messageLocation[i]];
+ //toPC.printf("WMsg MESSAGEINFO %5d %5d \n",
+ // msgHeader[i]->messageID,
+ // messageLocation[i]);
+
+ //calculated CRC
+ unsigned long CRC1 = CalculateBlockCRC32(28+msgHeader[i]->messageLength, &msgBuffer[messageLocation[i]]);
+ unsigned long CRC2 = *((unsigned long*)&msgBuffer[messageLocation[i] + 28 + msgHeader[i]->messageLength]);
+
+ if (CRC1 != CRC2)
+ {
+ TotalBadCRCmatches++;
+ toPC.printf(" bad CRC match for messageID %3d total CRC errors = %4d \n",
+ msgHeader[i]->messageID, TotalBadCRCmatches);
+ continue;
+ }
+
//test for a message 42 (BESTPOS)
if (msgHeader[i]->messageID == 42)
{
@@ -621,41 +309,53 @@
PPSTimeOffset = 0;
/////////////////////////////////////////////////////////////////////////////////////////
}
- }
+ } //end of per message loop
lookingForMessages = false;
+ if (recordData && (fpNav != NULL) && (byteCounter > 0))
+ {
+ wait_us(1000);
+ totalBytesWritten += fwrite(msgBuffer, 1, byteCounter, fpNav); // this writes out a complete set of messages for this sec
+ wait_us(1000);
+ }
+
} //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]
+ //GPSTime (secs from midnight) is from the header of the position message
+ //PPSTimeOffset accounts for time becoming known ~20msec AFTER the 1PPS
+ imuRec.GPSTime = GPSTimemsecs + PPSTimeOffset*1000 + timeFromPPS.read_us()/1000.0;
+ wait_us(10);
+ spi.write((int) HIGH_REGISTER[0]); wait_us(10); // 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]) ;
+ wd.pt[1] = (unsigned short)spi.write((int) LOW_REGISTER[i]); wait_us(10) ;
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]); }
+ { wd.pt[0] = (unsigned short)spi.write((int) HIGH_REGISTER[i+1]); wait_us(10); }
imuRec.dataWord[i] = wd.dataWord; //data word is a signed long
-
}
IMURecordCounter++;
//write the IMU data
- //if (recordData && (fpIMU != NULL))
if (recordData && (fpNav != NULL))
- {
- IMUbytesWritten += fwrite(imuRec.dataWord, sizeof(IMUREC), 1, fpNav);
+ {
+ totalBytesWritten += fwrite(&imuRec, 1, sizeof(IMUREC), fpNav);
}
IMUClockCounter++;
IMUDataReady = false;
}
+ /*
if (messageDetected) //some GPS message header has been detected
{
toPC.printf(" msgTime = %4d \n", timeFromPPS.read_us());
messageDetected = false;
}
+ */
if (camera1EventDetected) //we have detected a camera trigger event
{
@@ -665,13 +365,9 @@
if (detectedGPS1PPS) //true if we are exactly at a 1PPS event detection
{
- 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))
- {
- // 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
- }
+ //toPC.printf(" PPSCounter=%4d byteCounter=%10d Msgs Received=%3d IMUClock=%4d bytesWritten=%8d\n",
+ // PPSCounter, savedByteCounter, savedPerSecMessageCounter, savedIMUClockCounter, totalBytesWritten);
+
detectedGPS1PPS = false;
}
}