Diff: GPS.cpp

Revision:

0:db98027c0bbb

Child:

2:8aa059e7d8b1

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/GPS.cpp	Mon Nov 15 20:11:16 2010 +0000
@@ -0,0 +1,149 @@
+/*
+    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) 
+{
+    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, b;
+    
+    if (q == NULL) q = new GPS_Geodetic;
+    
+    do {
+        memcpy(&a, &thePlace, sizeof(GPS_Geodetic));
+        memcpy(&b, &thePlace, sizeof(GPS_Geodetic));
+    }
+    while (memcmp(&a, &b, sizeof(GPS_Geodetic)) != 0);
+    
+    return q;
+}
+
+void
+GPS::ticktock(void)
+{
+    // 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, "$GPRMC", 6)) {
+            theTime.nmea_rmc(s);
+            cb_rmc.call();
+            if (!_ppsInUse) theTime.fractionalReset();
+        }
+        else if (!strncmp(s, "$GPGGA", 6)) {
+            thePlace.nmea_gga(s);            
+            cb_gga.call();
+        }
+        process_required = false;
+    }
+}
+
+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); 
+            buffer[active_buffer][rx_buffer_in++] = c;
+            rx_buffer_in &= (GPS_BUFFER_LEN - 1);
+            if (c == '\n') {
+                active_buffer = active_buffer == 0 ? 1 : 0;
+                process_required = true;
+                rx_buffer_in = 0;                
+            }
+        }
+    }
+}