Trimble Outdoors SK8 - Manual (Page 159)

Lassen-SK8 Embedded GPS Module C-13
Trimble ASCII Interface Protocol (TAIP)
C.11 DD Delta Differential Corrections
This message provides the sensor with delta differential corrections from RTCM-104
record type 2. The values are numerical values written out in hex format, thus for each
byte of data there is a two digit hex number.
The format of the data string is as follows:
AAAABB{CCDDDD}
Table C-11. Delta Differential Corrections Data String Descriptions
*
Note – The units and scale factors are as defined by RTCM-104 version 1. The health/
UDRE/scale factor given for the specific SV in the most recent message DC is used. Delta
range corrections are scaled by 0.02 meters times 2 raised to the health power.
The DC and DD TAIP messages described herein apply only to differential ready sensors
and are provided to enclose differential corrections within the TAIP format.
Use of DC and DD messages to input corrections requires only one communications
channel. Use of the auxiliary port to input RTCM-104 corrections assumes a separate
communications channel is available for broadcast and receipt of differential corrections.
Note – The TAIP software toolkit, GPSSK, does not support DC and DD messages.
Item # of Char Type UNITS Format
Modified Z-count 4 WORD .6 sec AAAA
Number of SVs 2 BYTE n/a BB
The next 3 bytes (6 characters) are repeated for each SV
SV PRN 2 BYTE n/a CC
Delta Range
Correction 4 WORD RTCM-104 DDDD