BG95-M3, Spamming RDY over UART connnection

IoT Modules LPWA Module
1

Im using the NL-AB-RPI dev kit for a pi. When I connect to the BG95-B over UART using picocom, using the following command:

picocom -b 115200 -f h /dev/ttyAMA0

Every few seconds I get the unsolicited result code RDY. For about 1 second after the command is sent, I can type in any AT commands I want, but then it doesn’t except keyboard input until the next RDY result code is received. This makes it really frustrating to try and type any AT commands (as I have like 1 second to type it and then hit enter). It seems like the modem is getting constantly reset or something.

I’m not sure what would be causing this, as I am not trying to run any other programs or anything that would interfere with the DTO (which has been verified to load using: # cat /proc/device-tree/hat/product )

I would really appreciate some suggestions of where to go from here.

EDIT: Okay, so it appears I fixed it, special thanks to Dmitriy from product support.

Apparently, the QBG95 is somewhat unique in that it’s nRESET and ON_OFF signals are tied together internally in the module. The NL-AB-RPI weakly asserts low on the ON_OFF pin on the skywire modem which results in the QBG95 modem continuously resetting itself.

I had to manually turn the modem on using GPIO24 on the on RPI.

Thanks.

2

  1. pls double check your module vendor , based on your description ，it seem that this module does not product by quectel.

  2. one clue , pls confirm if PSM mode has be enabled in your module , if so , getting the RDY offen is normal

3

It is a quectel product, bought from digikey.

PSM has not been enabled.

I fixed the issue as seen above. Thanks.

4

Hi there, im having a similar issue. wondering what the fix was and how you were able to fix it? Thanks

5

I know this is reply is late but may be useful to others. Given the description this could be power related. If you are powering from a USB port then you likely don’t have enough current available. A standard USB will provide 500mA. As soon as you power in the modem it can start to register. If it attached to a 2G network then the peak power demand could be 2 Amp (for a very short period). Some dev boards have a bulk capacitor with a low ESR in place to smooth out these demands. This can help with USB powered but its not a fix. Use a USB power than can provide more current or use a Y cable to power from 2 ports and see if it becomes stable