ask for factory reset if GPS does not talk to us.

src/gps/NMEAGPS.cpp

@@ -17,6 +17,19 @@ static int32_t toDegInt(RawDegrees d)
     return r;
 }
 
+bool NMEAGPS::factoryReset()
+{
+#ifdef GPS_UBLOX
+        // Factory Reset
+        byte _message_reset[] = {0xB5, 0x62, 0x06, 0x09, 0x0D, 0x00, 0xFF,
+            0xFB, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0xFF, 0xFF, 0x00, 0x00, 0x17, 0x2B, 0x7E};
+        _serial_gps->write(_message_reset,sizeof(_message_reset));
+        delay(1000);
+        return true;
+#endif
+}
+
 bool NMEAGPS::setupGPS()
 {
     GPS::setupGPS();