Trimble Outdoors SK8 - Manual (Page 85)

Lassen-SK8 Embedded GPS Module A-21
Trimble Standard Interface Protocol
A.17.5 Command Packet 0x23
This packet provides the GPS receiver with an approximate initial position in XYZ
coordinates. This packet is useful if the user has moved more than a 1,000 miles after the
previous fix. (Note that the GPS receiver can initialize itself without any data from the
user; this packet merely reduces the time required for initialization.) This packet is ignored
if the receiver is already calculating positions. The data format is shown below.
To initialize with latitude-longitude-altitude, use Command Packet 0x 2B.
A.17.6 Command Packet 0x24
This packet requests current position fix mode of the GPS receiver. This packet contains
no data. The GPS receiver returns Packet
0x 6D.
A.17.7 Command Packet 0x25
This packet commands the GPS receiver to perform a software reset. This is equivalent to
cycling the power. The GPS receiver performs a self-test as part of the reset operation.
This packet contains no data. Following completion of the reset, the receiver will output
the start-up messages (see Table A-5). The GPS receiver sends Packet
0x 45 only on
power-up and reset (or on request); thus if Packet 0x 45 appears unrequested, then either
the GPS receiver power was cycled or the GPS receiver was reset.
A.17.8 Command Packet 0x26
This packet requests health and status information from the GPS receiver. This packet
contains no data. The GPS receiver returns packet
0x 46 and 0x 4B.
A.17.9 Command Packet 0x27
This packet requests signal levels for all satellites currently being tracked. This packet
contains no data. The GPS receiver returns Packet
0x 47.
A.17.10 Command Packet 0x28
This packet requests the most recent GPS system ASCII message sent with the navigation
data by each satellite. This packet contains no data. The GPS receiver returns Packet
0x 48.
Table A-16 Command Packet 0x23 Data Format
Byte Item Type Units
0-3 X Single Meters
4-7 Y Single Meters
8-11 Z Single Meters