HardFault when writing/erasing flash unless RTT debugger active

RE: HardFault when writing/erasing flash unless RTT debugger active

plippo — Tue, 17 Mar 2020 11:44:06 GMT

That was it! Very big THANK YOU! (A simple debug print of BPROT config registers confirmed this)

It looks like the default DFU bootloader marks all but the 0x7F000 page above bootloader start protected. We used to have a bootloader starting from 75000 so that debug version would fit. Unfortunately the DFU cannot change the bootloader start address when updating SD + BL, so now were stuck with it and had to use the 7D for our settings page.

So all I have to do is to modify our bootloader code to not mark the needed pages protected and we're good to go.

Thank you for a swift solution!

RE: HardFault when writing/erasing flash unless RTT debugger active

Vidar Berg — Mon, 16 Mar 2020 22:25:10 GMT

Maybe this page is protected by the BPROT? The protection gets disabled by default in debug interface mode, which could explain the behavior you are seeing.

RE: HardFault when writing/erasing flash unless RTT debugger active

plippo — Mon, 16 Mar 2020 13:14:28 GMT

It's a custom board (see: www.movesense.com).

I'll try to setup the UART debugging and see what's happening. Unfortunately we have communication protocol setup on top of UART so it may take some time to get it to work.

If you have any idea what could be different in MCU when RTT connection is up, please let me know. I'm assuming it's timing related but maybe not...

RE: HardFault when writing/erasing flash unless RTT debugger active

Simonr — Mon, 16 Mar 2020 13:09:13 GMT

Does this occur on a development kit (DK) or a custom board? Also, application are you running on your board, is it based on one of the SDK examples?

You can try to enable logging via UART if possible, that way you should be able to see the logs without being in debug mode.

Best regards,

Simon

RE: HardFault when writing/erasing flash unless RTT debugger active

plippo — Mon, 16 Mar 2020 12:20:25 GMT

The call to erase flash is nrf_fstorage_erase (1 page, address 0x7D000)