RAK3172 Randomly Loosing config when power is cut/re-supplied

The RAK3172 I am using seems to be loosing the:

  1. DevEUI
  2. AppEUI
  3. AppKEY
  4. Work Mode
  5. Region

Randomly when I remove and then re-apply power.
I am using it as a Modem, (I did not re-program the RAK3172)
I have only used 4 AT commands:

AT+APPEUI=XXX...
AT+APPKEY=XXX...
AT+JOIN...
AT+SEND...

I wanted the chip to keep its default DevEUI (like on the sticker)

I have not reset the chip using the reset command, and I did not update the FW.

AFTER seeing this issue, I did update the firmware to the latest version (released on the 25th)
I then set all of the config settings. AppEUI, DevEUI, AppKEY, Work Mode, Region.
The problem still randomly reoccures.

Any idea what may be going on?
Might it be a power issue? The power is coming from a 3.6v battery directly (within the upper range that the datasheet shows).

Thank you very much!

Hello @Kevin192291

Loosing means

  • reset to factory default
    or
  • set to zeros?

It is changing to all Zeros,
Factory defaults would be much better as I would be able to use the defaults on TTN

Is this

  • RAK3172 on a custom PCB
  • RAK3272 Breakout Board
  • RAK3271-E Evaluation Board

Normally, if the user settings are erased or damaged, it should start up with the factory defaults, but not with all zeros.

I will send this issue to our R&D team.

This is a custom board.
If you need, I can send the schematics.
Is there a way to do it in a more private way though?
Could this be a problem I have caused with a bad connections or something?

I found by re-setting the settings everytime, I am able to work-around the issue.
But this costs time, power. (and possibly write cycles?)

And an additional question, if it happens, are they permanent on zeros, or does another reboot solve the problem and the settings are back?

Did you connect the RST pin to anything or is it floating?
Could you try to put a pullup (10k) on the RST pin?

Can you send the problem to [email protected]. That is our customer support channel and we can talk more private there.

1 Like

Yes, the RST pin is currently Floating. I have made designed like that before using the RAK3172, I was under the impression that there is an internal pullup. is the not correct?

There is no pullup inside the RAK3172.
If you take the Breakout Board schematics as reference, there is a 10k/100nF on the RST line.