Section 11 - Beacon receiver binary protocol
PAGE 62
05/01/97 REV H
Request configuration
The hexadecimal control byte
C1
asks the 8800 to report its configuration
as a sequence of bytes on the RTCM SC-104 output port. The structure of
this reply follows:
•
C1
= message identifier
•
C0
+
msb6
= current frequency select, six MSBs
•
C0
+
lsb6
= current frequency select, six LSBs
•
Dn
= current bit rate select,
D4
–
D7
as defined above
•
F0
= indicates no EDAC method in use
•
F4
= indicates no interleave in use
•
Cn
= indicates software version “n”
Request status
The hexadecimal control byte
C5
asks the 8800 to report its current sta-
tus as a sequence of bytes on the RTCM SC-104 output port. The struc-
ture of this reply follows:
•
C5
= message identifier
•
C0
+
msb6
= encoded signal strength, six MSBs
•
C0
+
lsb6
= encoded signal strength, six LSBs
•
C0
+
snr
= encoded SNR, six bits
The signal strength is a 12-bit value that gives the strength in units of
dB
µ
V, with the special value 1 indicating that the 8800 isn’t currently
decoding RTCM SC-104 DGPS correction data. The SNR is the estimated
Signal-to-Noise Ratio in dB.
11.2 GPS binary protocol
The standard configuration for all Northstar sensors is NMEA protocol
NMEA 0183 Version 2.0; however, the sensors are capable of talking in
binary protocol (CMC binary). For details on this protocol, see Appendix
E, “CMC Binary Protocol,” in the
ALLSTAR OEM CMT-1200 Specifications
Rev H
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Summary of Contents for 8700
Page 2: ......
Page 10: ......
Page 16: ...Section 2 Introduction PAGE 6 05 01 97 REV H ...
Page 20: ...Section 3 Packaging PAGE 10 05 01 97 REV H ...
Page 32: ...Section 6 GPS beacon combination receivers PAGE 22 05 01 97 REV H ...
Page 46: ...Section 8 Input output configurations PAGE 36 05 01 97 REV H ...
Page 52: ...Section 9 Connector pinouts PAGE 42 05 01 97 REV H ...
Page 76: ...Section 12 8X00 engine monitor program PAGE 66 05 01 97 REV H ...
Page 78: ...Section 13 Glossary PAGE 68 05 01 97 REV H ...
Page 80: ...Section 14 Abbreviations and initialisms PAGE 70 05 01 97 REV H ...
Page 85: ...Index 05 01 97 REV H PAGE 75 ...