L76 PQPREC giving incorrect response

I have an L76 GNSS module (purchased this year) that I configure with;
PMTK220,100
PMTK301,2
PMTK313,1
PMTK285,3,2
PMTK353,1,1,0,0,1
PMTK386,0.1
PQPREC,W,6,6,3,1
PMTK314,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1

All commands except PQPREC and PMTK353 return success.
With PQPREC, the documentation says the module should return “PQPREC,W,OK” on success and “PQPREC,W,ERROR” on failure. Instead, the module echoes the command back and doesn’t change the precision of the output.

I’ve tried sending only PQPREC but the module still only echoes the command without changing precision.
Sending “PQPREC,R” also fails to report the current precision. The module similarly echoes the command back without including the current set precision.

What have I missed?

Dear Gaz,

  1. PMTK353 command, you could read the note in L76 GNSS protocol spec:
    GLONASS and BeiDou can not be enabled at the same time. Galileo and BeiDou can not be enabled at the same time too
    So PMTK353,1,1,0,0,1 is not supported.

  2. For PQPREC,W,6,6,3,1, do you send $PQPREC,W,6,6,3,1*7C?
    If yes, maybe your FW version doesn’t support this command.
    Please send command
    $PMTK605*31(response should be PMTK705)
    and $PQVERNO,R*3F, keep all reponse for me.

Hi Sammy,

  1. I should have read the docs closer. Thank you.

  2. Yes, I am sending $PQPREC,W,6,6,3,1*7C
    PMTK605 returns $PMTK705,AXN_3.8_3333_16042100,0006,Quectel-L76,1.0*0B
    PQVERNO,R returns $PQVERNO,R,L76NR02A07S,2016/04/22,12:44*6D

I think maybe your FW version is old, please try to upgrade to the latest version L76NR03A03S.
FW and user guide download link:https://cnquectel-my.sharepoint.com/:f:/g/personal/europe-fae_quectel_com/EvpnwMdrXmVFuvjFQy6wZDMBaFRPUiO7Al30qIJeLUvtqw?e=Xe8Ho4
Flashtool:https://cnquectel-my.sharepoint.com/:u:/g/personal/europe-fae_quectel_com/EZ-Yz3dfMFhCiKkGAKJQ4IEBNbvxdu3YkuTDs4rJCGi6PA?e=o8wJee

1 Like

That was it. Thank you Sammy. It’s all working now.