mtk3339.h

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#ifndef LIBPROPELLER_MTK3339_H_
#define LIBPROPELLER_MTK3339_H_

#include "libpropeller/gpsparser/gpsparser.h"
#include <propeller.h>

class MTK3339 : public GPSParser {
public:

    bool Start(int rxPin, int txPin, int ppsPin = -1){
        GPSParser::Start(rxPin, txPin, 9600);
        gpsStatus = CheckBaud();
        if (gpsStatus == true) { //GPS running at 9600
            //Update to 115200
            gps_serial_.PutFormatted(kPMTK_SET_NMEA_BAUDRATE_115200);
            waitcnt(CLKFREQ / 19 + CNT); //Make sure it's transmitted.
            gps_serial_.SetBaud(115200);
        } else { //GPS may be runnning at 115200
            gps_serial_.SetBaud(115200);
            gpsStatus = CheckBaud();
            if (gpsStatus == false) {
                return false;
            }
        }

        gps_serial_.PutFormatted(kPMTK_API_SET_NMEA_OUTPUT);
        gps_serial_.PutFormatted(kPMTK_SET_NMEA_UPDATE_10HZ);
        
        return GetStatus();

    }

    bool GetStatus(void) {
        return gpsStatus;
    }

    //TODO(SRLM): Add enter standby mode
    // PMTK_CMD_STANDBY_MODE

private:

    bool CheckBaud(void) {
        gps_serial_.GetFlush();
        waitcnt(CLKFREQ / 10 + CNT);
        gps_serial_.GetFlush();
        for (int i = 0; i < 50; i++) {
            unsigned char byte = (unsigned char) gps_serial_.Get();
            if (byte > (0x7F)) {
                return false;
            }
        }
        return true;
    }

    bool gpsStatus;

    static constexpr const char * kPMTK_SET_NMEA_UPDATE_10HZ = "$PMTK220,100*2F\r\n";
    static constexpr const char * kPMTK_SET_NMEA_BAUDRATE_115200 = "$PMTK251,115200*1F\r\n";
    static constexpr const char * kPMTK_API_SET_NMEA_OUTPUT = "$PMTK314,0,1,0,1,5,5,0,0,0,0,0,0,0,0,0,0,0,0,0*28\r\n";




};

#endif // LIBPROPELLER_MTK3339_H_