Unable to downgrade nRF9160 modem firmware from 1.0.1 to 1.0.0

RE: Unable to downgrade nRF9160 modem firmware from 1.0.1 to 1.0.0

Jleguen — Thu, 24 Oct 2019 16:24:45 GMT

Hi,

I finally figured it out, somehow the MAGPIO table got flushed and the RF switches on the board were not properly configured... Well that will teach me not to rely too much on the non-volatile storage :)

Thank you for the help!

RE: Unable to downgrade nRF9160 modem firmware from 1.0.1 to 1.0.0

Jleguen — Wed, 23 Oct 2019 15:05:43 GMT

Hi,

I finally managed to connect with the nRF9160DK devkit, with mfw v1.0.1 and the iBasis SIM. It also worked with an Orange SIM (I'm in France). It connected almost immediately, so what I'm experiencing is definitely not a network issue.

The issue is that I'm still unable to connect to LTE with my custom board. The radio hardware is based on the Thingy:91 schematics. Please note that it was also able to connect extremely rapidly (in seconds) to the network last week, we did not make any changes to the hardware.
I'm guessing the modem configuration got scrambled somehow, but I fail to see how it happened and do not know how to restore its factory state.

Both boards run the mfw_1.0.1 firmware and the AT_CLIENT sample code, files were gathered using the nRFConnect Link Monitor and Trace Collector.

Thank you for your help!

devzone.nordicsemi.com/.../2019_2D00_10_2D00_23T14_5F00_49_5F00_06.645Z_2D00_log_5F00_devkit_5F00_ibasis_5F00_ok.txt devzone.nordicsemi.com/.../trace_2D00_2019_2D00_10_2D00_23T14_2D00_49_2D00_46.112Z_5F00_devkit_5F00_ibasis_5F00_ok.bin devzone.nordicsemi.com/.../2019_2D00_10_2D00_23T14_5F00_54_5F00_24.717Z_2D00_log_5F00_custom_5F00_ibasis_5F00_fail.txt devzone.nordicsemi.com/.../trace_2D00_2019_2D00_10_2D00_23T14_2D00_54_2D00_46.464Z_5F00_custom_5F00_ibasis_5F00_fail.bin

RE: Unable to downgrade nRF9160 modem firmware from 1.0.1 to 1.0.0

Martin Lesund — Wed, 23 Oct 2019 10:29:23 GMT

Note: it is not possible to downgrade to previous modem firmware releases after applying this upgrade.

So you were able to connect to the LTE-M network without any issues with the nrf9160 with the mfw v1.0.0?
Are you using the iBasis SIM card or local carrier SIM card?

Please share the LTE link monitor log from when you are trying to connect and it would be nice if you could share a modem trace then we can figure out what is going wrong.