In Quectel_LC29H_SeriesLC79HAL_GNSS_Protocol_Specification_V1.2.pdf the command “830 PAIR_RAW_ENABLE” is described as “Enables/disables outputting binary raw measurement.” However this protocol doesn’t seem to be documented. Could I get documentation for this, in particular option 2 which includes SV and PVT information?
Hi Luke,
I guess you need binary protocol which reports GNSS raw data. You need to send PAIR432 command to enable RTCM output. And please refer to supported RTCM protocol. You will have an official protocol from https://www.rtcm.org/.
Best regards.
The binary protocol that this enables matches with the MTK binary format that I’m finding referenced online. It looks like Airoha kept at least the header (0x04 0x24) and footer values (0x0D 0xA).
There are references to this binary format in the Quectel EPO documentation; but I’m very interested in the SV and PVT information that gets turned on by the $PAIR830,2*2F command.
SV information is not included in the RTCM protocol messages that are produced by the Quectel firmware, so I’m hoping that this can work for my application.
Hi Luke,
Can you tell me which kind of binary protocol you need?
Best regards.
Hello,
I would also like to know if there is any documentation about the binary data (protocol) provided when enabling:
$PAIR830,2*2F
When i enable this, i can see an increase of data (indeed starting with the 0x04 0x24)
With kind regards,
Mathijs
Hi Mathijs,
The message start with 0x04 0x24 is binary format data. We don’t have documents about binary protocol.
Binary code to ASCII:
0x04 = End of text;
0x24 = $
Also standard NMEA message start with 0x04 0x24 in binary format.
Best regards.
Since there is no documentation available for binary raw measurements, here are some findings i did on my own.
04 24 Preamble
XX XX Command
XX XX Length (DATA)
XX XX XX XX XX XX (This is the DATA section)
XX (Checksum8 XOR of Command, Length and Data)
AA 44
0D 0A
Depending on the setting (PAIR830,1 or PAIR830,2), there are several packets spawn.
When you enable just PAIR830,1 you will get data of command 0x0FA1 (A1 0F)
The data section of that command seems to be: (example)
XX XX XX XX XX XX XX XX (64bit kind of timer? GPS clock? Little endian
XX XX GPS weeknumber (e.g. 01 09 = 0x901 = 2305)
00 12 ?? No clue
XX Number of SV data followed after this header (32 byte packets each)
XX 8bit group counter. This is the same with packets with other command that belong to this dataset.
00 00 ?? No clue yet
<n * 32byte SV data>
About the SV data. No clue yet on them, but the 2nd byte does like to indicate PRN (for GPS), the 4th byte indicate SNR ratio of receiver. Seems to be some timers, ephemeris, etc.
Perhaps/Surely I am re-inventing the wheel, but could not find any matching information available
regards,
Mathijs