Diff: MODGPS/GPS.cpp
- Revision:
- 0:bec310bde899
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/MODGPS/GPS.cpp Tue Sep 27 19:46:30 2011 +0000
@@ -0,0 +1,236 @@
+/*
+ Copyright (c) 2010 Andy Kirkham
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+*/
+
+#include "GPS.h"
+
+GPS::GPS(PinName tx, PinName rx, const char *name) : Serial(tx, rx, name)
+{
+ _nmeaOnUart0 = false;
+
+ _lastByte = 0;
+
+ _gga = (char *)NULL;
+
+ _rmc = (char *)NULL;
+
+ _vtg = (char *)NULL;
+
+ switch(_uidx) {
+ case 1: _base = LPC_UART1; break;
+ case 2: _base = LPC_UART2; break;
+ case 3: _base = LPC_UART3; break;
+ default : _base = NULL; break;
+ }
+
+ _pps = NULL;
+ _ppsInUse = false;
+
+ if (_base != NULL) attach(this, &GPS::rx_irq);
+
+ _second100 = new Ticker;
+ _second100->attach_us(this, &GPS::ticktock, GPS_TICKTOCK);
+}
+
+void
+GPS::ppsAttach(PinName irq, ppsEdgeType type)
+{
+ if (_pps != NULL) delete(_pps);
+ _pps = new InterruptIn(irq);
+ if (type == ppsRise) _pps->rise(this, &GPS::pps_irq);
+ else _pps->fall(this, &GPS::pps_irq);
+ _ppsInUse = true;
+}
+
+void
+GPS::ppsUnattach(void)
+{
+ if (_pps != NULL) delete(_pps);
+ _ppsInUse = false;
+}
+
+double
+GPS::latitude(void)
+{
+ double a, b;
+ do { a = thePlace.lat; b = thePlace.lat; } while (a != b);
+ return a;
+}
+
+double
+GPS::longitude(void)
+{
+ double a, b;
+ do { a = thePlace.lon; b = thePlace.lon; } while (a != b);
+ return a;
+}
+
+double
+GPS::altitude(void)
+{
+ double a, b;
+ do { a = thePlace.alt; b = thePlace.alt; } while (a != b);
+ return a;
+}
+
+GPS_Geodetic *
+GPS::geodetic(GPS_Geodetic *q)
+{
+ GPS_Geodetic a;
+
+ if (q == NULL) q = new GPS_Geodetic;
+
+ do {
+ memcpy(&a, &thePlace, sizeof(GPS_Geodetic));
+ memcpy(q, &thePlace, sizeof(GPS_Geodetic));
+ }
+ while (memcmp(&a, q, sizeof(GPS_Geodetic)) != 0);
+
+ return q;
+}
+
+GPS_VTG *
+GPS::vtg(GPS_VTG *q)
+{
+ GPS_VTG a;
+
+ if (q == NULL) q = new GPS_VTG;
+
+ do {
+ memcpy(&a, &theVTG, sizeof(GPS_VTG));
+ memcpy(q, &theVTG, sizeof(GPS_VTG));
+ }
+ while (memcmp(&a, q, sizeof(GPS_VTG)) != 0);
+
+ return q;
+}
+
+void
+GPS::ticktock(void)
+{
+ int i;
+
+ // Increment the time structure by 1/100th of a second.
+ ++theTime;
+
+ // Test the serial queue.
+ if (process_required) {
+ char *s = buffer[active_buffer == 0 ? 1 : 0];
+ if (!strncmp(s, "$GPRMC", 6)) {
+ if (_rmc) {
+ for(i = 0; s[i] != '\n'; i++) {
+ _rmc[i] = s[i];
+ }
+ _rmc[i++] = '\n'; _rmc[i] = '\0';
+ }
+ theTime.nmea_rmc(s);
+ cb_rmc.call();
+ if (!_ppsInUse) theTime.fractionalReset();
+ }
+ else if (!strncmp(s, "$GPGGA", 6)) {
+ if (_gga) {
+ for(i = 0; s[i] != '\n'; i++) {
+ _gga[i] = s[i];
+ }
+ _gga[i++] = '\n'; _gga[i] = '\0';
+ }
+ thePlace.nmea_gga(s);
+ cb_gga.call();
+ }
+ else if (!strncmp(s, "$GPVTG", 6)) {
+ if (_vtg) {
+ for(i = 0; s[i] != '\n'; i++) {
+ _vtg[i] = s[i];
+ }
+ _vtg[i++] = '\n'; _vtg[i] = '\0';
+ }
+ theVTG.nmea_vtg(s);
+ cb_vtg.call();
+ }
+ else {
+ if (_ukn) {
+ for(i = 0; s[i] != '\n'; i++) {
+ _ukn[i] = s[i];
+ }
+ _ukn[i++] = '\n'; _ukn[i] = '\0';
+ cb_ukn.call();
+ }
+ }
+ process_required = false;
+ }
+
+ // If we have a valid GPS time then, once per minute, set the RTC.
+ if (theTime.status == 'A' && theTime.second == 0 && theTime.tenths == 0 && theTime.hundreths == 0) {
+ // set_time() is defined in rtc_time.h
+ // http://mbed.org/projects/libraries/svn/mbed/trunk/rtc_time.h
+ set_time(theTime.to_C_tm());
+ }
+
+}
+
+void
+GPS::pps_irq(void)
+{
+ theTime.fractionalReset();
+ theTime++; // Increment the time/date by one second.
+ cb_pps.call();
+}
+
+void
+GPS::rx_irq(void)
+{
+ uint32_t iir __attribute__((unused));
+ char c;
+
+ if (_base) {
+ iir = (uint32_t)*((char *)_base + GPS_IIR);
+ while((int)(*((char *)_base + GPS_LSR) & 0x1)) {
+ c = (char)(*((char *)_base + GPS_RBR) & 0xFF);
+
+ // strtok workaround.
+ // Found that ,, together (which some NMEA sentences
+ // contain for a null/empty field) confuses strtok()
+ // function. Solution:- Push a "zero" into the string
+ // for missing/empty fields.
+ if (c == ',' && _lastByte == ',') {
+ buffer[active_buffer][rx_buffer_in] = '0';
+ if (++rx_buffer_in >= GPS_BUFFER_LEN) rx_buffer_in = 0;
+ }
+
+ // Debugging/dumping data.
+ if (_nmeaOnUart0) LPC_UART0->RBR = c;
+
+ // Put the byte into the string.
+ buffer[active_buffer][rx_buffer_in] = c;
+ if (++rx_buffer_in >= GPS_BUFFER_LEN) rx_buffer_in = 0;
+
+ // Save for next time an irq occurs. See strtok() above.
+ _lastByte = c;
+
+ // If end of NMEA sentence flag for processing.
+ if (c == '\n') {
+ active_buffer = active_buffer == 0 ? 1 : 0;
+ process_required = true;
+ rx_buffer_in = 0;
+ }
+ }
+ }
+}
Willem Melching