Updated
Fork of GPS by
Revision 2:233e5e68fbfb, committed 2014-11-18
- Comitter:
- canterol
- Date:
- Tue Nov 18 03:03:52 2014 +0000
- Parent:
- 1:1d60e6a0ffd9
- Commit message:
- Updated
Changed in this revision
GPS.cpp | Show annotated file Show diff for this revision Revisions of this file |
--- a/GPS.cpp Sat Nov 02 16:17:58 2013 +0000 +++ b/GPS.cpp Tue Nov 18 03:03:52 2014 +0000 @@ -1,4 +1,5 @@ -/* mbed GPS Module Library +/* + * mbed GPS Module Library * Copyright (c) 2008-2010, sford * Copyright (c) 2013, B.Adryan * @@ -19,26 +20,39 @@ * 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. + * + * Modified by: Ben Wallace + * Modification Date: 10/20/2014 + * GPS Module: Adafruit Ultimate GPS V3 + * uController: LPC1768 */ #include "GPS.h" -GPS::GPS(PinName tx, PinName rx, int Baud) : _gps(tx, rx) { +GPS::GPS(PinName tx, PinName rx, int Baud) : _gps(tx, rx) +{ _gps.baud(Baud); longitude = 0.0; latitude = 0.0; } -int GPS::sample() { +int GPS::sample() +{ char ns, ew, unit; int lock; + + float degrees; + float minutes; - while(1) { + while(1) + { getline(); // Check if it is a GPGGA msg (matches both locked and non-locked msg) - if(sscanf(msg, "GPGGA,%f,%f,%c,%f,%c,%d,%d,%f,%f,%c,%f", &time, &latitude, &ns, &longitude, &ew, &lock, &sats, &hdop, &alt, &unit, &geoid) >= 1) { - if(!lock) { + if(sscanf(msg, "GPGGA,%f,%f,%c,%f,%c,%d,%d,%f,%f,%c,%f", &time, &latitude, &ns, &longitude, &ew, &lock, &sats, &hdop, &alt, &unit, &geoid) >= 1) + { + if(!lock) + { time = 0.0; longitude = 0.0; latitude = 0.0; @@ -47,42 +61,66 @@ alt = 0.0; geoid = 0.0; return 0; - } else { + } + + else + { //GPGGA format according http://aprs.gids.nl/nmea/#gga // time (float), lat (f), (N/S) (c), long (f), (E/W) (c), fix (d), sats (d), // hdop (float), altitude (float), M, geoid (float), M, , , //GPGGA,092010.000,5210.9546,N,00008.8913,E,1,07,1.3,9.7,M,47.0,M,,0000*5D - if(ns == 'S') { latitude *= -1.0; } - if(ew == 'W') { longitude *= -1.0; } - float degrees = trunc(latitude / 100.0f); - float minutes = latitude - (degrees * 100.0f); - latitude = degrees + minutes / 60.0f; - degrees = trunc(longitude / 100.0f * 0.01f); - minutes = longitude - (degrees * 100.0f); - longitude = degrees + minutes / 60.0f; + minutes = fmod((double)latitude, 100.0); //Modulate by 100.0 to convert dddmm.mmmm to mm.mmmm + minutes /= 60.0; //Convert minutes to degrees (1 degree = 60 minutes) + degrees = ((int)latitude / 100); //Divide by 100 and truncate to convert dddmm.mmmm to ddd.000000 + latitude = degrees + minutes; //Combine degrees and minutes into a single degree value + + minutes = fmod((double)longitude, 100.0); //Modulate by 100.0 to convert dddmm.mmmm to mm.mmmm + minutes /= 60.0; //Convert minutes to degrees (1 degree = 60 minutes) + degrees = ((int)longitude / 100); //Divide by 100 and truncate to convert dddmm.mmmm to ddd.000000 + longitude = degrees + minutes; //Combine degrees and minutes into a single degree value + + //If the latitude is designated 'South" then multiply the latitude by -1.0 + if(ns == 'S') + { + latitude *= -1.0; + } + + //If the longitude is designated 'West" then multiply the longitude by -1.0 + if(ew == 'W') + { + longitude *= -1.0; + } + return 1; } } } } -float GPS::trunc(float v) { +float GPS::trunc(float v) +{ if(v < 0.0) { v*= -1.0; v = floor(v); v*=-1.0; - } else { + } + + else + { v = floor(v); } return v; } -void GPS::getline() { +void GPS::getline() +{ while(_gps.getc() != '$'); // wait for the start of a line - for(int i=0; i<256; i++) { + for(int i=0; i<256; i++) + { msg[i] = _gps.getc(); - if(msg[i] == '\r') { + if(msg[i] == '\r') + { msg[i] = 0; return; }