No modem response from SARA SFF

Hi there!

I tried to communicate with the SARA modem on the SARA SFF but couldn’t get it to run with my RIOT based application on the SAMD21. I tried to use the Arduino passthrough sketch instead, but the serial monitor is not giving me any responses from the modem at all. So I finally tried the Universal Tracker sketch but for the “SV” command, for example, I only get
:
11:36:42.019 -> Enter command: SV
11:36:43.561 -> Initializing modem…
11:36:49.795 -> Modem initialized.
11:36:49.795 -> Modem version:
11:36:49.795 -> Please note that the modem is now initialized.
11:36:49.795 -> *** If you need to change the type of network please reboot first.
11:36:49.830 ->
11:36:49.830 -> Commands:
11:36:49.830 -> Show IMEI (SI):
11:36:49.830 -> Show CCID (SC):
11:36:49.830 -> Show Module version (SV):
11:36:49.830 -> Commit Settings (CS):

Please also note the long delay during modem initialization. Do I have a hardware issue or do I miss anything?

Hi @olha,

When you uploaded the sketch, did you select “SODAQ SFF” and not “SODAQ SARA”?

Best regards,
Jan

Hi @Jan,

I selected “SODAQ SFF”, but if I retrieve the Board Info it shows “BN: SODAQ SARA”.

Cheers
Oliver

Hi @olha,

The Arduino IDE will show the first SAMD21 board in your list, in your case this is always “BN: SODAQ SARA”.

What module is on the SODAQ SFF? And what is the ntype= you have selected?
If you have an R412M, you need to connect the battery. Without a battery it can’t communicate to the R412M modem.

Best regards,
Jan

Hey @jan,

thanks for your support. We managed to solve the problem. Apparently it was caused by removing the solder jumper for charging the battery. After closing the solder jumper again, communication with the modem works again.

Cheers
Oliver

1 Like

Hi @olha,

Thanks for letting us know the issue is solved.

Best regards,
Jan

Unfortunately, not quite solved apparently. The board is currently powered over USB only - could this be the problem? How would we connect a battery? We failed to find a documentation.

Hi @olha,

I see you have bought an SFF R412M, due to the potential battery usage of the 2G the module get’s it’s power directly from the battery. You can connect the battery which should have been in your package to the JST connector with “battery” written next to it.

You can find all documentation on our support pages, https://support.sodaq.com/Boards/Sara_SFF/
If you need more information, you can always reach out on this forum.

Best regards,
Jan