Diff: Sensors/GPS/GPS.cpp

Revision:

0:826c6171fc1b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Sensors/GPS/GPS.cpp	Wed Jun 20 14:57:48 2012 +0000
@@ -0,0 +1,176 @@
+// For SiRF III
+
+#include "GPS.h"
+
+extern Serial pc;
+
+
+
+
+GPS::GPS(PinName tx, PinName rx, int type):
+    hdop(0.0),
+    serial(tx, rx)
+{
+    setType(SIRF);
+    setBaud(4800);
+} 
+
+
+void GPS::setType(int type)
+{
+    if (type == VENUS || type == MTK || type == SIRF) {
+        _type = type;
+    }
+    
+    return;
+}
+
+void GPS::setBaud(int baud)
+{
+    serial.baud(baud);
+    
+    return;
+}
+
+void GPS::setUpdateRate(int rate)
+{
+    char msg[10] = { 0xA0, 0xA1, 0x00, 0x03,
+                    0x0E, rate&0xFF, 01,
+                    0, 0x0D, 0x0A };
+    for (int i=4; i < 7; i++) {
+        msg[7] ^= msg[i];
+    }
+    switch (rate) {
+    case 1 :
+    case 2 :
+    case 4 :
+    case 5 :
+    case 8 :
+    case 10 :
+    case 20 :
+        for (int i=0; i < 10; i++)            
+            serial.putc(msg[i]);
+        break;
+    default :
+        break;
+    }
+}
+
+void GPS::setNmeaMessages(bool gga, bool gsa, bool gsv, bool gll, bool rmc, bool vtg)
+{
+    if (_type == VENUS) {
+        // VENUS Binary MsgID=0x08
+        // GGA interval
+        // GSA interval
+        // GSV interval
+        // GLL interval
+        // RMC interval
+        // VTG interval
+        // ZDA interval -- hardcode off
+        char msg[15] = { 0xA0, 0xA1, 0x00, 0x09, 
+                         0x08, gga, gsa, gsv, gll, rmc, vtg, 0,
+                         0, 0x0D, 0x0A };
+        for (int i=4; i < 12; i++) {
+            msg[12] ^= msg[i];
+        }
+        for (int i=0; i < 15; i++)
+            serial.putc(msg[i]);
+    }
+}
+    
+
+void GPS::gsvMessage(bool enable)
+{
+    if (enable) {
+        if (_type == MTK) {
+            serial.printf("$PSRF103,03,00,01,01*26\r\n");     // Enable GSV
+        } else if (_type == VENUS) {
+        }
+    } else {
+        if (_type == MTK) {
+            serial.printf("$PSRF103,03,00,00,01*27\r\n");     // Disable GSV
+        } else if (_type == VENUS) {
+            // ??
+        }
+    }
+
+    return;
+}
+
+void GPS::gsaMessage(bool enable)
+{
+    if (enable) {
+        if (_type == SIRF) {
+            serial.printf("$PSRF103,02,00,01,01*27\r\n");     // Enable GSA
+        } else if (_type == VENUS) {
+            // ??
+        }
+    } else {
+        if (_type == SIRF) {
+            serial.printf("$PSRF103,02,00,00,01*26\r\n");     // Disable GSA
+        } else if (_type == VENUS) {
+            // ??
+        }
+    }
+    
+    return;
+}
+
+
+// Handle data from a GPS (there may be two GPS's so needed to put the code in one routine
+//
+void GPS::process(GeoPosition &here, char *date, char *time)
+{
+    double lat, lon;
+    unsigned long age;
+    
+    nmea.reset_ready(); // reset the flags
+    //pc.printf("%d GPS RMC are ready\n", millis);
+    nmea.f_get_position(&lat, &lon, &age);
+    nmea.crack_datetime(&year, &month, &day, &hour, &minute, &second, &hundredths, &age);
+
+    sprintf(date, "%02d/%02d/%4d", month, day, year);
+    sprintf(time, "%02d:%02d:%02d.%03d", hour, minute, second, hundredths);
+
+    hdop = nmea.f_hdop();
+
+    // Bearing and distance to waypoint
+    here.set(lat, lon);
+
+    //pc.printf("HDOP: %.1f gyro: %d\n", gps1_hdop, gyro);
+
+    return;
+}
+
+
+void GPS::init()
+{    
+    // Initialize the GPS comm and handler
+    //serial.baud(57600); // LOCOSYS LS20031
+    //DigitalIn myRx(_rx);
+    //Timer tm;
+
+
+/*    
+    //pc.printf("gps.init()\n\n");
+    int rate = 99999999;
+    for (int i=0; i < 10; i++) {    
+        //pc.printf("rate: %d\n", rate);
+        while( myRx ); // wait for low
+        tm.reset();
+        tm.start();
+        while ( !myRx ); // wait for high
+        if (tm.read_us() < rate) rate = tm.read_us();
+    }
+*/
+    if (_type == MTK) {
+        gsvMessage(false);      // Disable GSV
+        gsaMessage(false);      // Disable GSA
+    } else if (_type == VENUS) {
+        setNmeaMessages(true, true, false, false, true, false);
+        setUpdateRate(10);
+    }
+    
+    // Synchronize with GPS
+    nmea.reset_ready();
+}
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