I am trying to integrate the RAK12501 module into my project. I am using a driver written for the L76K specifically and I have the source code (to test mods if necessary). It appears that the device will not respond to any PMTK commands. I do, however, see plenty of satellite commands coming from the device.
($ and *CRC value omitted)
For example, the command to set the PPS mode to disabled
send: PMTK285,0,100
expect: PMTK001,285,3
actual: no response (failure, device set to disabled)
This is one example. PMTK commands are not being responded to per the protocol spec (v2.2). I am suspecting that this is not in fact a Quectel L76K but a variant.
Is this expected behavior?
Is this an L76K from Quectel or a variant?
Is there an updated protocol spec for whichever actual device is being shipped with this module?
The Quectel L76K module does not support PMTK commands; it uses the newer PCAS command set instead. Therefore, commands like PMTK_CMD_HOT_START or PMTK225 for periodic mode are not applicable to the L76K and will not work. You must refer to the module’s protocol specification to use the correct PCAS commands for configuration and control.
And the module is an original Quectel module, not a variant.
Thanks for the information. It seems that none of the existing drivers either in zephyr or other quectel related repositories have an appropriate driver other than the nmea generic one which offers no device control (understandably).
I’m adapting a quectel Lx6 driver to the L76K specifically. The lack of an ACK from the PCAS commands is interesting. At least I can leverage the NMEA parsing routines from Zephyr.
Thanks again for your help.