usen usen / MODGPS

Allows for a GPS module to be connected to a serial port and exposes an easy to use API to get the GPS data. New feature, added Mbed/LPC17xx RTC synchronisation

Fork of MODGPS by Andy K

GPS.cpp@0:db98027c0bbb, 2010-11-15 (annotated)

Committer:
AjK
Date:
Mon Nov 15 20:11:16 2010 +0000
Revision:
0:db98027c0bbb
Child:
2:8aa059e7d8b1
1.8

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AjK 0:db98027c0bbb 1 /*
AjK 0:db98027c0bbb 2 Copyright (c) 2010 Andy Kirkham
AjK 0:db98027c0bbb 3
AjK 0:db98027c0bbb 4 Permission is hereby granted, free of charge, to any person obtaining a copy
AjK 0:db98027c0bbb 5 of this software and associated documentation files (the "Software"), to deal
AjK 0:db98027c0bbb 6 in the Software without restriction, including without limitation the rights
AjK 0:db98027c0bbb 7 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
AjK 0:db98027c0bbb 8 copies of the Software, and to permit persons to whom the Software is
AjK 0:db98027c0bbb 9 furnished to do so, subject to the following conditions:
AjK 0:db98027c0bbb 10
AjK 0:db98027c0bbb 11 The above copyright notice and this permission notice shall be included in
AjK 0:db98027c0bbb 12 all copies or substantial portions of the Software.
AjK 0:db98027c0bbb 13
AjK 0:db98027c0bbb 14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
AjK 0:db98027c0bbb 15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
AjK 0:db98027c0bbb 16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AjK 0:db98027c0bbb 17 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
AjK 0:db98027c0bbb 18 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
AjK 0:db98027c0bbb 19 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
AjK 0:db98027c0bbb 20 THE SOFTWARE.
AjK 0:db98027c0bbb 21 */
AjK 0:db98027c0bbb 22
AjK 0:db98027c0bbb 23 #include "GPS.h"
AjK 0:db98027c0bbb 24
AjK 0:db98027c0bbb 25 GPS::GPS(PinName tx, PinName rx, const char *name) : Serial(tx, rx, name)
AjK 0:db98027c0bbb 26 {
AjK 0:db98027c0bbb 27 switch(_uidx) {
AjK 0:db98027c0bbb 28 case 1: _base = LPC_UART1; break;
AjK 0:db98027c0bbb 29 case 2: _base = LPC_UART2; break;
AjK 0:db98027c0bbb 30 case 3: _base = LPC_UART3; break;
AjK 0:db98027c0bbb 31 default : _base = NULL; break;
AjK 0:db98027c0bbb 32 }
AjK 0:db98027c0bbb 33
AjK 0:db98027c0bbb 34 _pps = NULL;
AjK 0:db98027c0bbb 35 _ppsInUse = false;
AjK 0:db98027c0bbb 36
AjK 0:db98027c0bbb 37 if (_base != NULL) attach(this, &GPS::rx_irq);
AjK 0:db98027c0bbb 38
AjK 0:db98027c0bbb 39 _second100 = new Ticker;
AjK 0:db98027c0bbb 40 _second100->attach_us(this, &GPS::ticktock, GPS_TICKTOCK);
AjK 0:db98027c0bbb 41 }
AjK 0:db98027c0bbb 42
AjK 0:db98027c0bbb 43 void
AjK 0:db98027c0bbb 44 GPS::ppsAttach(PinName irq, ppsEdgeType type)
AjK 0:db98027c0bbb 45 {
AjK 0:db98027c0bbb 46 if (_pps != NULL) delete(_pps);
AjK 0:db98027c0bbb 47 _pps = new InterruptIn(irq);
AjK 0:db98027c0bbb 48 if (type == ppsRise) _pps->rise(this, &GPS::pps_irq);
AjK 0:db98027c0bbb 49 else _pps->fall(this, &GPS::pps_irq);
AjK 0:db98027c0bbb 50 _ppsInUse = true;
AjK 0:db98027c0bbb 51 }
AjK 0:db98027c0bbb 52
AjK 0:db98027c0bbb 53 void
AjK 0:db98027c0bbb 54 GPS::ppsUnattach(void)
AjK 0:db98027c0bbb 55 {
AjK 0:db98027c0bbb 56 if (_pps != NULL) delete(_pps);
AjK 0:db98027c0bbb 57 _ppsInUse = false;
AjK 0:db98027c0bbb 58 }
AjK 0:db98027c0bbb 59
AjK 0:db98027c0bbb 60 double
AjK 0:db98027c0bbb 61 GPS::latitude(void)
AjK 0:db98027c0bbb 62 {
AjK 0:db98027c0bbb 63 double a, b;
AjK 0:db98027c0bbb 64 do { a = thePlace.lat; b = thePlace.lat; } while (a != b);
AjK 0:db98027c0bbb 65 return a;
AjK 0:db98027c0bbb 66 }
AjK 0:db98027c0bbb 67
AjK 0:db98027c0bbb 68 double
AjK 0:db98027c0bbb 69 GPS::longitude(void)
AjK 0:db98027c0bbb 70 {
AjK 0:db98027c0bbb 71 double a, b;
AjK 0:db98027c0bbb 72 do { a = thePlace.lon; b = thePlace.lon; } while (a != b);
AjK 0:db98027c0bbb 73 return a;
AjK 0:db98027c0bbb 74 }
AjK 0:db98027c0bbb 75
AjK 0:db98027c0bbb 76 double
AjK 0:db98027c0bbb 77 GPS::altitude(void)
AjK 0:db98027c0bbb 78 {
AjK 0:db98027c0bbb 79 double a, b;
AjK 0:db98027c0bbb 80 do { a = thePlace.alt; b = thePlace.alt; } while (a != b);
AjK 0:db98027c0bbb 81 return a;
AjK 0:db98027c0bbb 82 }
AjK 0:db98027c0bbb 83
AjK 0:db98027c0bbb 84 GPS_Geodetic *
AjK 0:db98027c0bbb 85 GPS::geodetic(GPS_Geodetic *q)
AjK 0:db98027c0bbb 86 {
AjK 0:db98027c0bbb 87 GPS_Geodetic a, b;
AjK 0:db98027c0bbb 88
AjK 0:db98027c0bbb 89 if (q == NULL) q = new GPS_Geodetic;
AjK 0:db98027c0bbb 90
AjK 0:db98027c0bbb 91 do {
AjK 0:db98027c0bbb 92 memcpy(&a, &thePlace, sizeof(GPS_Geodetic));
AjK 0:db98027c0bbb 93 memcpy(&b, &thePlace, sizeof(GPS_Geodetic));
AjK 0:db98027c0bbb 94 }
AjK 0:db98027c0bbb 95 while (memcmp(&a, &b, sizeof(GPS_Geodetic)) != 0);
AjK 0:db98027c0bbb 96
AjK 0:db98027c0bbb 97 return q;
AjK 0:db98027c0bbb 98 }
AjK 0:db98027c0bbb 99
AjK 0:db98027c0bbb 100 void
AjK 0:db98027c0bbb 101 GPS::ticktock(void)
AjK 0:db98027c0bbb 102 {
AjK 0:db98027c0bbb 103 // Increment the time structure by 1/100th of a second.
AjK 0:db98027c0bbb 104 ++theTime;
AjK 0:db98027c0bbb 105
AjK 0:db98027c0bbb 106 // Test the serial queue.
AjK 0:db98027c0bbb 107 if (process_required) {
AjK 0:db98027c0bbb 108 char *s = buffer[active_buffer == 0 ? 1 : 0];
AjK 0:db98027c0bbb 109 if (!strncmp(s, "$GPRMC", 6)) {
AjK 0:db98027c0bbb 110 theTime.nmea_rmc(s);
AjK 0:db98027c0bbb 111 cb_rmc.call();
AjK 0:db98027c0bbb 112 if (!_ppsInUse) theTime.fractionalReset();
AjK 0:db98027c0bbb 113 }
AjK 0:db98027c0bbb 114 else if (!strncmp(s, "$GPGGA", 6)) {
AjK 0:db98027c0bbb 115 thePlace.nmea_gga(s);
AjK 0:db98027c0bbb 116 cb_gga.call();
AjK 0:db98027c0bbb 117 }
AjK 0:db98027c0bbb 118 process_required = false;
AjK 0:db98027c0bbb 119 }
AjK 0:db98027c0bbb 120 }
AjK 0:db98027c0bbb 121
AjK 0:db98027c0bbb 122 void
AjK 0:db98027c0bbb 123 GPS::pps_irq(void)
AjK 0:db98027c0bbb 124 {
AjK 0:db98027c0bbb 125 theTime.fractionalReset();
AjK 0:db98027c0bbb 126 theTime++; // Increment the time/date by one second.
AjK 0:db98027c0bbb 127 cb_pps.call();
AjK 0:db98027c0bbb 128 }
AjK 0:db98027c0bbb 129
AjK 0:db98027c0bbb 130 void
AjK 0:db98027c0bbb 131 GPS::rx_irq(void)
AjK 0:db98027c0bbb 132 {
AjK 0:db98027c0bbb 133 uint32_t iir __attribute__((unused));
AjK 0:db98027c0bbb 134 char c;
AjK 0:db98027c0bbb 135
AjK 0:db98027c0bbb 136 if (_base) {
AjK 0:db98027c0bbb 137 iir = (uint32_t)*((char *)_base + GPS_IIR);
AjK 0:db98027c0bbb 138 while((int)(*((char *)_base + GPS_LSR) & 0x1)) {
AjK 0:db98027c0bbb 139 c = (char)(*((char *)_base + GPS_RBR) & 0xFF);
AjK 0:db98027c0bbb 140 buffer[active_buffer][rx_buffer_in++] = c;
AjK 0:db98027c0bbb 141 rx_buffer_in &= (GPS_BUFFER_LEN - 1);
AjK 0:db98027c0bbb 142 if (c == '\n') {
AjK 0:db98027c0bbb 143 active_buffer = active_buffer == 0 ? 1 : 0;
AjK 0:db98027c0bbb 144 process_required = true;
AjK 0:db98027c0bbb 145 rx_buffer_in = 0;
AjK 0:db98027c0bbb 146 }
AjK 0:db98027c0bbb 147 }
AjK 0:db98027c0bbb 148 }
AjK 0:db98027c0bbb 149 }