At Pass Through Gen 3 B5SOM, PANIC Hard Fault, cannot put into DFU or Safe mode

Firmware
1

Hi All,

We loaded the at passthrough firmware onto a B5SOM and a BSOM for compliance testing.

The at-passthrough firmware was successfully installed on both machines and both behaved as expected from the firmware.

We had to make some changes to the firmware, which we did, then recompiled and attempted to reflash using the dfu-util. This worked successfully for the BSOM, but while flashing the B5SOM, we got the following error.

Opening DFU capable USB device...
Device ID 2b04:d019
Device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Interface #0 ...
Determining device status...
DFU state(2) = dfuIDLE, status(0) = No error condition is present
DFU mode device DFU version 011a
Device returned transfer size 4096
DfuSe interface name: "Internal Flash   "
Downloading element to address = 0x00030000, size = 557092
Erase           [======================   ]  88%       491520 bytesdfu-util: Error during special command "ERASE_PAGE" get_status
make[2]: *** [program-dfu] Error 74
make[1]: *** [flash-debug] Error 2
make: *** [flash-debug] Error 2

Since this error occured the device now immediately goes in a SOS panic with hard fault (1 flash). The device is not recognisable over USB and cannot be placed in safemode or factory reset. Is their anyway to recover this device or is it bricked?

Device is a B524 SOM, has been retrofitted with an MFF2 to 4FF Nano sim card adaptor.

Similar issues:

2

Have you attempted restoring the device with a Jlink and Jflash? I've found this to be a very effective debricking method when I've messed with bootloaders.

Alternatively, flashing the hex files directly with Device Restore JTAG | Tools | Particle with the debugger or nrfjprog usually does the trick.

It's also possible the device was damaged during the adaptor soldering steps.