Revision 5:fdac9c46157b, committed 2018-03-05

Comitter:

WilliamO7

Date:

Mon Mar 05 16:17:03 2018 +0000

Parent:

4:147f30d69bf6

Child:

6:c22b014ae4d0

Commit message:

return number of satellites found

Changed in this revision

--- a/GPS.cpp	Sun Mar 04 23:17:28 2018 +0000
+++ b/GPS.cpp	Mon Mar 05 16:17:03 2018 +0000
@@ -20,29 +20,34 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
+#include <cstdlib>
 #include "GPS.h"
 
 GPS::GPS(PinName tx, PinName rx) : _gps(tx, rx) {
     _gps.baud(4800);    
     longitude = 0.0;
     latitude = 0.0;  
-    time_utc = 0.0;      
+    time_utc = 0.0;
+    sats = 0;   
 }
 
 int GPS::sample() {
     float time;
     char ns, ew;
     int lock;
+    char satnum_buf[2];
 
     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", &time, &latitude, &ns, &longitude, &ew, &lock) >= 1) { 
-            if(!lock) {
+        if(sscanf(msg, "GPGGA,%f,%f,%c,%f,%c,%d,%s", &time, &latitude, &ns, &longitude, &ew, &lock, satnum_buf) >= 1) { 
+            int satnum = std::atoi(satnum_buf);
+            if(!lock || satnum < 4) {
                 longitude = 0.0;
                 latitude = 0.0;   
-                time_utc = 0.0;     
+                time_utc = 0.0; 
+                sats = satnum;    
                 return 0;
             } else {
                 if(ns == 'S') {    latitude  *= -1.0; }
@@ -54,6 +59,7 @@
                 minutes = longitude - (degrees * 100.0f);
                 longitude = degrees + minutes / 60.0f;
                 time_utc = time;
+                sats = satnum; 
                 return 1;
             }
         }

--- a/GPS.h	Sun Mar 04 23:17:28 2018 +0000
+++ b/GPS.h	Mon Mar 05 16:17:03 2018 +0000
@@ -49,6 +49,9 @@
     /** The time in UTC float format (call sample() to set) */
     float time_utc;
     
+    /** Number of satellites (call sample() to set) */
+    int sats;
+    
 private:
     float trunc(float v);
     void getline();