APPENDIX B: GARMIN BINARY OUTPUT FORMAT

Note: The following applies to all software versions of GPS 16xLVS and GPS 16xHVS.

Two records are transmitted once per second by the GPS 16x series products. One record contains primarily postprocess information, such as position and velocity information. The second record contains receiver measurement information. The records are sent at a default baud rate of 9600 baud, 8 data bits, and no parity.

Records begin with a delimiter byte (10 hex). The second byte identifies the record type (33 hex for a position record, 34 hex for a receiver measurement). The third byte indicates the size of the data. The fourth byte is the first byte of data. The data is then followed by a checksum byte, a delimiter byte (10 hex), and an end-of-transmission character (03 hex).

Note: If RTCM-104 differential data is sent to the GPS sensor, the board will reset the Garmin Binary Output Data baud rate to the same baud rate used for RTCM-104 data. If the differential inputs are used on the GPS sensor, the RTCM-104 data must be sent to the GPS sensor at 9600 baud (preferred) or 4800 baud. RTCM-104 baud rates less than 4800 baud are not supported by the GPS sensors as it would limit bus bandwidth past the point where a once- per-second Garmin binary output data rate could be maintained.

Position Record

- 0x10

(DLE is first byte)

- 0x33

(Position record identifier)

- 0x40

(Size of data)

- cpo_pvt_data

(See description below)

- one-byte checksum

(The addition of bytes between the delimiters should equal 0)

- 0x10

(DLE)

- 0x03

(ETX is last byte)

typedef struct

 

{

alt;

float

float

epe;

float

eph;

float

epv;

int

fix;

double

gps_tow;

double

lat;

double

lon;

float

lon_vel;

float

lat_vel;

float

alt_vel;

float

msl_hght;

int

leap_sec;

long

grmn_days;

} cpo_pvt_data;

190-00228-08

GPS 16x Technical Specifications

Rev. A

 

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