alt

Ellipsoid altitude (meters)

epe

Estimated position error (meters)

eph

Position error, horizontal (meters)

epv

Position error, vertical (meters)

fix

0 = no fix; 1 = no fix; 2 = 2D; 3 = 3D; 4 = 2D differential; 5 = 3D differential;

 

6 and greater = not defined

gps_tow

GPS time of week (sec)

lat

Latitude (radians)

lon

Longitude (radians)

lon_vel

Longitude velocity (meters/second)

lat_vel

Latitude velocity (meters/second)

alt_vel

Altitude velocity (meters/ second)

msl_hght

height (mean sea level) (meters)

leap_sec

UTC leap seconds

grmn_days

Garmin days (days since December 31, 1989)

Satellite Data Record

The satellite data has a record ID of 0x72 with 84 (0x54) data bytes. The data bytes contain data for 12 satellites as described below.

typedef

struct

 

{

svid; //space vehicle identification (1–32 and 33–64 for WAAS)

uint8

uint16

snr;

//signal-to-noise ratio

uint8

elev; //satellite elevation in degrees

uint16

azmth;

//satellite azimuth in degrees

uint8

status;

//status bit-field

} cpo_sat_data;

The status bit field represents a set of booleans described below:

Bit

Meaning when bit is one (1)

0The unit has ephemeris data for the specified satellite.

1The unit has a differential correction for the specified satellite.

2The unit is using this satellite in the solution.

This pattern is repeated for 12 satellites for a total of 12 X 7 bytes = 84 (0x54) bytes.

The RS-232 Packet for the Satellite Record looks like:

- 0x10

(DLE is first byte)

- 0x72

(Record ID – single byte)

- 0x54

(Number of data bytes – single byte)

- 12 cpo_sat_data records

 

- 0x##

(2’s complement of the arithmetic sum of the bytes between the delimiters)

- 0x10

(DLE)

- 0x03

(ETX is last byte)

The USB Packet for the Satellite Record looks like:

- 0x72

(Record ID – single byte)

- 0x54

(Number of data bytes – single byte)

- 12 cpo_sat_data records

 

190-00228-08

GPS 16x Technical Specifications

Rev. A

 

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