ashtech DG16 Reference Manual page 275

The data fields common to each MSG message are listed in Table 8.26:
Fields
d1 RTCM message type
d2 Station Identifier
f3 Z count
d4 Sequence number
d5 Station health
d6 Total number of characters following the time tag
(including commas and <CR><LF> characters)
m7 Current GPS time of position fix (hhmmss.ss)
Table 8.27 lists the remainder of the MSG message for RTCM type 1. The remainder
for RTCM type 9 is identical.
Fields
d8
d9
f10
f11
d12
*hh
Table 8.28 lists the remainder of the MSG message for RTCM type 2:
Fields
d8 User differential range error (UDRE)
d9 Satellite PRN Number
f10 Delta Pseudo range correction (Delta PRC) in
meters
NMEA Commands
Table 8.26. Common MSG Data Fields
Description
Table 8.27. Remainder of Type 1
Description
User differential range error (UDRE)
Satellite PRN number
Pseudo range correction (PRC) in
meters
Range rate correction (RRC) in meters/
sec
Issue of data ephemeris (IODE)
Checksum
Table 8.28. Remainder of Type 2 Message
Description
Range
1, 2, 3, 6, 9, 16
0 to 1023
0 to 9999.9
0 to 9
0 to 7
0 to 999
00 to235959.90
Range
0 to 9
1 to32
±9999.99
±9.999
0 to 999
2-character
hex
Range
0 to 9
1 to 32
±
99.99
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