 {
   pinMode(GPS_POWER, OUTPUT);
   char* GPSString;
-  char* disable = "$PSRF103,i,00,00,01*xxxxxx";
+  char* protocol =  "$PSRF100,1,4800,8,1,0*0E"; // NMEA
+  char* disable =   "$PSRF103,02,00,00,01*26\r\n";
   char* querryGGA = "$PSRF103,00,01,00,01*25";
   bool GPS_available = false;
   Serial3.begin(GPSRATE);   
   digitalWrite(GPS_POWER, LOW);         // pull low to turn on!
+  Serial.flush();
+  Serial3.flush();
+  delay(5000);
+  // prints title with ending line break 
+  Serial.println(" GPS parser");  
 //  Serial.print("Acquiring GPS RMC...");
+  checksum(protocol);
+  Serial3.println(protocol);
+  disable[10] = '2';
+  checksum(disable);
+  Serial3.println(disable);   // no GSA
+
   GPS_available = estimated_position.AcquireGPRMC(70000);
   Serial.println(TimeHeader);
   Serial.println(StartTime);

{ 
    pinMode(Rx0, INPUT);
    pinMode(Tx0, OUTPUT);
    pinMode(GPS_POWER, OUTPUT);
    Serial3.begin(GPSRATE);    
    Serial.begin(9600);
    // prints title with ending line break 
    Serial.println("GPS parser");  
    digitalWrite(GPS_POWER, LOW);         // pull low to turn on!
    // make sure that the default chip select pin is set to
    // output, even if you don't use it:

        pData = estimated_position.formDataString();
        if (dataFile) dataFile.print(pData);
        Serial.print(pData);
        Serial3.print(pData);  // send data to C4 path planner
        pObstacles = obstacleDetect();
        if (dataFile) 
        {
