Trimble Outdoors SK8 - Manual (Page 114)

A-50 Lassen-SK8 Embedded GPS Module
Trimble Standard Interface Protocol
A.17.45 Command Packet 0x65
This packet requests the status of differential corrections for a specific satellite or for all
satellites for which data is available. This packet contains only one byte specifying the
PRN number of the desired satellite or zero to request all available. The response is a
Packet
0x 85 for each satellite if data is available. If the receiver has no valid data for any
satellite, no reply will be sent.
A.17.46 Report Packet 0x6D
This packet provides a list of satellites used for position fixes by the GPS receiver. The
packet also provides the PDOP, HDOP, and VDOP of that set and provides the current
mode (automatic or manual, 3-D or 2-D). This packet has variable length equal to 16+nsvs
where “nsvs” is the number of satellites used in the solution.
The GPS receiver sends this packet in response to Packet 0x 24 when the receiver is doing
an overdetermined fix or every 5 seconds. The data format is shown in Table A-53.
Table A-53. Report Packet 0x6D Data Formats
Report 6D Byte Item Type Meaning
0 overdetermined mode BYTE BIT Value Meaning
0-2 3 2D
4 3D
3 0 Auto
1 Manual
4-7 -- nsvs
1-4 PDOP SINGLE PDOP
5-8 HDOP SINGLE HDOP
9-12 VDOP SINGLE VDOP
13-16 TDOP SINGLE TDOP
(16+nsvs) SV PRN BYTE