GPS( )

Compatible with:
DOS Maximite CMM MM150 MM170 MM+ MMX Picromite ArmiteL4 Armite F4 ArmiteH7 Picomite CMM2

Syntax:
GPS(option)
PRINT #GPS, string$

Description:

The GPS functions are used to return data from a serial communications channel opened as GPS.  
GPS uses the $GNGGA, $GNRMC, $GPGGA and $GPRMC messages.

The function GPS(VALID) should be checked before any of these functions are used to ensure that the returned value is valid.  

GPS(ALTITUDE)   Returns current altitude (if sentence GGA is enabled).  
GPS(DATE)   Returns the normal date string corrected for local time e.g. 12-01-2020.  
GPS(DOP)   Returns DOP (dilution of precision) value (if sentence GGA is enabled).  Low numbers are better.
GPS(FIX)   Returns 0=no fix, 1=fix, etc. if sentence GGA enabled
GPS(GEOID)   Returns the geoid-ellipsoid separation (if sentence GGA is enabled).  
GPS(LATITUDE)   Returns the latitude in degrees as a floating point number,  values are negative for South of equator  
GPS LONGITUDE)   Returns the longitude in degrees as a floating point number,  values are negative for West of the meridian.  
GPS(SATELLITES)   Returns number of satellites in view (if sentence GGA is enabled).  
GPS(SPEED)   Returns the ground speed in knots as a floating point number.  
GPS(TIME)   Returns the normal time string corrected for local time e.g. 12:09:33.  
GPS(TRACK)   Returns the track over the ground (degrees true) as a floating point number.  
GPS(VALID)   Returns: 0=invalid data, 1=valid data  
PRINT #GPS, string$   Outputs a NMEA string to an opened GPS device. The string must start with a $ character and end with a * character. The checksum is calculated automatically by the firmware and is appended to the string together with the carriage return and line feed characters.  

 

 OPEN "com1: 9600" AS GPS,10
 DO
   IF GPS(VALID) THEN
     PRINT GPS(TIME), GPS(LATITUDE), GPS(LONGITUDE), GPS(ALTITUDE);
     PRINT GPS(SATELLITES), GPS(DOP), GPS(FIX)
   ELSE
     PRINT GPS(SATELLITES), GPS(DOP), GPS(FIX)
   ENDIF
   PAUSE 1000
 LOOP
 CLOSE GPS
END


Last edited: 25 February, 2021