Losing settings after power save MAX-M8Q

0 votes

I am setting power save mode to "PSMCT" on MAX-M8Q. Device goes into low power mode but loses settings on power up. I am saving settings using cfg-cfg. I have set to save to devBBR, that pin is permanently supplied with power. The device I have is protocol V15.

Is there something else to do?

by ChangedDaily asked Dec 6
0 votes
Do you ever assert RESET_N? If yes, don't.
Verify your V_BCKP doesn't droop when the system switches to backup mode or back to full power mode.
Use u-center to formulate/verify your CFG-CFG "save to all memories" command.
by grampy answered Dec 6
Hi, I am not asserting RESET_N and the V_BCKP is solid. I think the problem may be that I have disabled all NMEA messages except ZDA but this setting of course isn't saved. When resuming from sleep all the NMEA messages restart. This made me think the settings weren't being saved. It is a problem for me though. All the NMEA messages seem to prevent the return to a power saving mode and I will have to somehow turn off the messages again. The alternative I guess is to switch off NMEA altogether and try to find some suitable UBX messages. Unless you have any other ideas? Thanks
Assuming your hardware attestation is valid, the evidence you offer indicates that none of your configuration settings are being saved OR that your code or Windows 10 is clearing all your changes and returning to factory defaults

If you are using Windows 10, remove completely the Location/Sensor USB driver and replace it with the simple CDC-ACM VCP driver found on the u-blox website.

If you are running your own code, verify that you never issue a CFG-CFG command to restore factory defaults.

Use u-center to verify your CFG-CFG command that saves your settings to BBRAM.

If all this checks out, then its back to hardware troubleshooting which is not easily done through forum posts.
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