nrf528520 BLE DFU OTA Issue

RE: nrf528520 BLE DFU OTA Issue

Hung Bui — Fri, 20 Jun 2025 08:08:45 GMT

Hi Noaman,

Please double check which pin is assigned as NRF_BL_DFU_ENTER_METHOD_BUTTON_PIN in your code.

Also please check the level of this pin in a normal application , it should be at VDD and not at GND. If it's at GND (0) then it will keep the bootloader to stay in DFU mode. See dfu_enter_check() in the nrf_bootloader.c file. If you don't plan to put the device to DFU mode via a pin, you would need to set NRF_BL_DFU_ENTER_METHOD_BUTTON to 0 in sdk_config.h of the bootloader.

RE: nrf528520 BLE DFU OTA Issue

Stratosphere — Fri, 20 Jun 2025 00:46:07 GMT

Hi Hung,

Here is the schematic. P0.16 is tied to ACC Int 2 pin which is disabled by default.

What there anything in the files I shared that may be indicated any issue?

I can try to take the motion sensor off the board and try. But is that the only thing? I could also disable the button option and test.

Regards

Noaman

RE: nrf528520 BLE DFU OTA Issue

Hung Bui — Wed, 18 Jun 2025 12:52:37 GMT

Hi Noaman,
My suggestion is to try flashing with the bootloader debug build so that you can step in the code and see what could be wrong.

Have you disabled the option to enter DFU via a button press (NRF_BL_DFU_ENTER_METHOD_BUTTON) ? If not there could be a chance that the button (P0.16- Button4 on the DK) is held active when the device booting => always enter DFU mode.

One another thing you should try is to test on a DK to see if your application start.