usb dfu bootloader with GPREGRET entrance Cause cannot get out the bootloader mode

RE: usb dfu bootloader with GPREGRET entrance Cause cannot get out the bootloader mode

weizhen — Mon, 14 Sep 2020 15:53:13 GMT

I found the issue, I must to set the flag to 0xB1 to make it work

RE: usb dfu bootloader with GPREGRET entrance Cause cannot get out the bootloader mode

weizhen — Mon, 14 Sep 2020 15:35:49 GMT

this cause clear gpregret never happened

if (NRF_BL_DFU_ENTER_METHOD_GPREGRET &&
((nrf_power_gpregret_get() & BOOTLOADER_DFU_GPREGRET_MASK) == BOOTLOADER_DFU_GPREGRET)
&& (nrf_power_gpregret_get() & BOOTLOADER_DFU_START_BIT_MASK))
{
// Clear DFU mark in GPREGRET register.
nrf_power_gpregret_set(nrf_power_gpregret_get() & ~BOOTLOADER_DFU_START);
}

I have no idea what should I set to NRF_POWER->GPREGRET, I tried 0x00000001 and 0xF8 | 0x01, and nothing changed

RE: usb dfu bootloader with GPREGRET entrance Cause cannot get out the bootloader mode

weizhen — Mon, 14 Sep 2020 14:54:15 GMT

<debug> app: Enter nrf_bootloader_fw_activate
<info> app: No firmware to activate.
<debug> app: App is valid
<debug> app: DFU mode requested via GPREGRET.
<info> nrf_bootloader_wdt: WDT is not enabled
<debug> app: in weak nrf_dfu_init_user
<debug> app: timer_stop (0x2000002C)
<debug> app: timer_activate (0x2000002C)
<info> app: Entering DFU mode.
<info> app: BOOTLOADER INIT
<debug> app: Initializing transports (found: 1)
<debug> nrf_dfu_serial_usb: Initializing drivers.
<debug> nrf_dfu_serial_usb: Starting USB
<debug> nrf_dfu_serial_usb: USB Transport initialized
<debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
<debug> app: Enter main loop
<info> nrf_dfu_serial_usb: USB power detected
<info> nrf_dfu_serial_usb: USB ready

feels like the GPREGRET is not cleaned.

RE: usb dfu bootloader with GPREGRET entrance Cause cannot get out the bootloader mode

Sigurd — Mon, 07 Sep 2020 07:17:07 GMT

Hi,

The function dfu_enter_flags_clear() should clear the GPREGRET BOOTLOADER_DFU_START field. You should use the debug variant of the bootloader, debug and check why the app won't start. It could be wrong CRC, wrong SoftDevice version used, etc.

What nrfutil command did you use to generate the DFU package?

What SDK version are you using? What SoftDevice version are you using ?