freertos with wdt reset problem, nrfjprog

[twittich]

Hello

my setup is a nrf52840, the sdk15.3, Softdevice s140.

I'm running an application with freertos and wdt and have the openbootloader and s140 also flashed.

- if in freertos the wdt is disabled and i set the GPREGRET register and make a reset with NVIC_SystemReset, i have to make a reset from outside by nrfjprog -r over jlink and then the dfu device comes up...

- and after update the device over dfu it has to be reset by nrfjprog -r and it resetarts in application as wanted

- If the wdt is enabled and do the same, set the GPREGRET register and make a reset with NVIC_SystemReset, the device restarts in application....

How can i make a reset or restart similar to nrfjprog -r from software so that no jlink is needed ?

Thanks in advance

twittich

[twittich]

I debugged the application... After calling " nrf_power_gpregret_set(0xB1); " it jumps to " 00000A60  4B01 " and ends up at " 0002A968  BE00 "  " NRF_BREAKPOINT_COND; " in  " app_error_weak.c ".

After that if i do same procedure with nrfjprog -r the dfu isn't coming up. To work like before i have to reflash the device. I have just seen that if i start debug the application the part of the bootloader before the softdevice in flash is deleted,  (checked with nrf connect) 0x00000FF8 - 0x00001000. The mbr is still there 0x00000000 - 0x00000B00

If i debug the bootloader, i call in the application the function which includes the " nrf_power_gpregret_set(0xB1); " and " self reset " then in bootloader debug it starts at " 00000A60  4B01 " then end up at " 0002A968 BE00". Not coming to the first breakpoint which is "  ret_val = nrf_bootloader_init(dfu_observer); " ( the previous code with flash protect is commented out )  Hanging in Unknon function. After pressing " restart debug " dfu comes up.

Bluetooth is not used. The bootloader uses dfu over usb-serial.

In the file see after debug and before.
flash bootloader part deleted after app debug.pdf

[Vidar Berg]

twittich said:

I debugged the application... After calling " nrf_power_gpregret_set(0xB1); " it jumps to " 00000A60  4B01 " and ends up at " 0002A968  BE00 "  " NRF_BREAKPOINT_COND; " in  " app_error_weak.c ".

nrf_power_gpregret_set() accesses the register directly which is not allowed when you have the Softdevice enabled, see Error handling, Memory isolation and runtime protection and Hardware peripherals. This is why your code ends up in the app error handler. You should use SD APIs you mentioned earlier to access grepregret instead:

err_code = sd_power_gpregret_clr(0, 0xffffffff);
VERIFY_SUCCESS(err_code);

err_code = sd_power_gpregret_set(0, BOOTLOADER_DFU_START);
VERIFY_SUCCESS(err_code);

0x6A0 is the address of the Hardfault exception handler inside the MBR. 

[twittich]

Yes i also just tried the sd function and that was the problem.

And now i have to feed the dog from the bootloader.

[Vidar Berg]

Excellent, thanks for the update. So everything works now, or do you need more help with the WD part? 

[twittich]

I have to find out where the bootloader is waiting for the dfu update start that i can insert there the wd reload.

Maybe it will work with the " loop_forever " function in " nrf_bootloader.c " ?

But there is already a function named " nrf_bootloader_wdt_feed(); " ?