Hi,
I'm trying to downgrade the nRF9160 modem firmware from 1.0.1 to 1.0.0. I'm currently unable to connect to LTE network from a location where I was connecting in seconds beforehand. This is critical because even in locations where the LTE network is around -60dBm (measured with my phone) the modem does not connect.
Re-flashing the 1.0.1 works flawlessly so this is not an issue with my software configuration.
When trying to downgrade with nRFConnect I get the following log :
2019-10-22T16:30:48.533Z INFO Recovery procedure finished
2019-10-22T16:30:48.547Z INFO Using nrfjprog to communicate with target
2019-10-22T16:30:50.188Z INFO Using J-Link Software version 6.48
2019-10-22T16:30:52.318Z INFO Segger serial: 600114712
2019-10-22T16:30:52.319Z INFO Segger speed: 2000 kHz
2019-10-22T16:30:52.319Z INFO Segger version: J-Link V10 compiled Jul 23 2019 13:46:10
2019-10-22T16:30:52.328Z INFO Probed: 600114712.
2019-10-22T16:30:52.328Z INFO Model: NRF9160_xxAA_FUTURE.
2019-10-22T16:30:52.328Z INFO RAM: 256KiB.
2019-10-22T16:30:52.328Z INFO Flash: 1024KiB in pages of 4KiB.
2019-10-22T16:30:53.784Z INFO Reading device non-volatile memory. This may take a few seconds.
2019-10-22T16:31:07.457Z INFO Modem DFU starts to write...
2019-10-22T16:31:07.457Z INFO Writing to device with serial number: 600114712
2019-10-22T16:31:07.457Z INFO Writing to device with file: E:\nordic\modem_upgrade\mfw_nrf9160_1.0.0.zip
2019-10-22T16:31:09.589Z INFO Checking file 1 of 7 files.
2019-10-22T16:31:09.590Z INFO Finished with file.
2019-10-22T16:31:09.593Z INFO Checking file 2 of 7 files.
2019-10-22T16:31:09.595Z INFO Finished with file.
2019-10-22T16:31:09.597Z INFO Checking file 3 of 7 files.
2019-10-22T16:31:09.605Z INFO Programming file.
2019-10-22T16:31:09.637Z INFO Programming 1 of 1 segments.
2019-10-22T16:31:09.728Z INFO Programming finished.
2019-10-22T16:31:09.731Z INFO Finished with file.
2019-10-22T16:31:09.735Z INFO Checking file 4 of 7 files.
2019-10-22T16:31:09.738Z INFO Programming file.
2019-10-22T16:31:14.423Z INFO Programming 1 of 33 segments.
2019-10-22T16:31:14.873Z ERROR Modem DFU failed with error: Error: Error occured when program. Errorcode: CouldNotCallFunction (0x9)
Lowlevel error: Unknown value (ffffff23)
What solution do I have to get my modem to work again?
Thanks