nrf52832 OTA over ESB based on SDK17.1.0

[Lurn_Z]

Hi everyone:    I developed an application based on ESB wireless communication protocol ofr the nRF52832, and I would like to perform an OTA DFU with it.    Do you know any example of some over the air FW upgrade of nRF52832 chip via ESB protocol.

    SDK is 17.1.0.

Best regards,

Lurn.

[Lurn_Z]

Edvin said:

Are you resetting manually in this log (using nrfjprog --reset) or is it the timer that times out? 

nope, it is the times out.

I clear the register by nrf_power_gpregret_set(nrf_power_gpregret_get() & ~BOOTLOADER_DFU_START); and then I print the nrf_power_gpregret_get() value, it is 0, So I think the register was cleared.

Edvin said:

I am not sure what you mean by the while loop anymore

The while loop is that. I put the code in the preceding part of my main.c.

void enter_dfu()
{
    uint32_t old_gpregret = nrf_power_gpregret_get();
    uint32_t new_gpregret = old_gpregret & BOOTLOADER_DFU_START; //Just to retain other things written to gpregret. Not necessarily needed.
    uint32_t temp = 0;
    
    nrf_power_gpregret_set(0XB1);
    while ((temp & BOOTLOADER_DFU_START) != BOOTLOADER_DFU_START)
    {
        // Wait until the gpregret is written, and refresh the value of temp.
        nrf_power_gpregret_get(0, &temp);
    }
    // When this is reached, the gpregret is successfully written.
    nrf_pwr_mgmt_shutdown(NRF_PWR_MGMT_SHUTDOWN_GOTO_DFU);
    NVIC_SystemReset();
}

int main(void)
{
    SEGGER_RTT_printf(0, "Start Application");
    nrf_drv_clock_init();
    clocks_start();
    bsp_board_init(BSP_INIT_LEDS);
    enter_dfu();
    ...
}

And this is the process, after I program the MBR, bootloader, application and settings, it will always in DFU mode, and I wasn't use the nrfjprog --reset in this log, it is the time out.

 The order of commands I used.

Fullscreen cmd.txt Download

nrfutil settings generate --family NRF52 --application app.hex --application-version 0 --bootloader-version 0 --bl-settings-version 2 settings.hex
nrfutil pkg generate --application app.hex --application-version 2 --sd-req 0x00 --hw-version 52 --key-file priv.pem dfu_image.zip

nrfjprog --eraseall -f NRF52
nrfjprog --program mbr_nrf52_2.4.1_mbr.hex --verify -f NRF52
nrfjprog --program bootloader.hex --verify -f NRF52
nrfjprog --program app.hex --verify -f NRF52
nrfjprog --program settings.hex --verify -f NRF52
nrfjprog --reset -f NRF52

and the logs

Fullscreen bootloader_logs.log Download

# SEGGER J-Link RTT Viewer V7.00a Terminal Log File
# Compiled: 15:35:52 on Apr 16 2021
# Logging started @ 23 Feb 2023 14:26:17
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x2<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initia<debug> app: ti<de<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app:<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: ACTIVATION_NONE
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: Clear DFU mark in GPREGRET register.
00> 
00> <debug> app: GPREGRET register = 0.
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 

# Logging stopped @ 23 Feb 2023 14:28:17

You can see that I was clear the register and read the value in my new logs, but the device didn't enter application.

BR,

Lurn

[Edvin]

Ok, you need to debug why it still enters:

00> <debug> app: DFU mode requested via GPREGRET.

after you cleared it. 

Can you please show me how you clear the register (set it to 0)?

BR,
Edvin

[Lurn_Z]

Edvin said:

Can you please show me how you clear the register (set it to 0)?

In nrf_bootloader.c It have the function dfu_enter_flags_clear(); and my code ran into there

nrf_power_gpregret_set(nrf_power_gpregretget() & ~ BOOTLOADER_DFU_START);

after then I use nrf_power_gpregretget() to get value again, and the value is 0;

Now, I have a new discovery.

Before then, I program all the hex, they only have bootloader logs without application logs.

But, when I program all the hex, and debug the application, I found that I can see the application logs but no bootloader logs.

I set a break point in my main.c before the code run to my function enter_dfu();

It was triggered again, and the time between triggered, it not much different from NRF_BL_DFU_INACTIVITY_TIMEOUT_MS.

So, I change the time value of the macro, and the time interval was also changed.

I think maybe it was enter the application, It's just reset by application and return to DFU (because my function is in the front of the main();)?

But why is there no log printing?

BR,

Lurn

[Edvin]

Hello Lurn,

It may be that if RTT logging is enabled in both the bootloader and the application, that when you open an RTT terminal, it will only find the first one. I am not too familiar with the details, but it uses RAM that the debugger reads out. If it finds a dedicated buffer in the bootloader, it may stop searching, and don't look for the buffer from the application.

If the bootloader is working, you can use the non-debug version of the bootloader, so that the RTT viewer will find the application. Alternatively, you can try to open several RTT viewers, where you specify what address to open. You can find where the RTT buffers are located by reading out the RAM:

nrfjprog --memrd 0x20000000 --n 0x10000 >> ram_dump.txt

When I tested this, I got:

This is on address 0x20003EB4 (it is the 5th byte on line 0x20003EB0, starting from 0). 

When I enter this address manually in RTT viewer, I can see the log:

So you need to find both the strings in RAM saying "SEGGER RTT", and open these addresses manually. Note that when you search for SEGGER RTT, they may not be on one line, so if you can't find one of them, search for "SEG" and "RTT", and you will probably find it. 

BR,
Edvin

[Lurn_Z]

ok, I was try it, and the log also only have bootloader logs.

Fullscreen bootloader_0224.txt Download

> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Des<debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20000020)
00> 
00> <info> app: Inactivity timeout.
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20000020)
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20000020)
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings:<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20000020)
00> 
00> <info> app: Inactivity timeout.
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_fire (0x20000020)
00> 
00> <info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <info> nrf_dfu_settings: Backing up settings page to address 0x7E000.
00> 
00> <debug> nrf_dfu_settings: Destination settings are identical to source, write not needed. Skipping.
00> 
00> <debug> app: Enter nrf_bootloader_fw_activate
00> 
00> <info> app: No firmware to activate.
00> 
00> <debug> app: App is valid
00> 
00> <debug> app: DFU mode requested via GPREGRET.
00> 
00> <info> nrf_bootloader_wdt: WDT is not enabled
00> 
00> <debug> app: in weak nrf_dfu_init_user
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: timer_activate (0x20000020)
00> 
00> <info> app: Entering DFU mode.
00> 
00> <debug> app: Initializing transports (found: 1)
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init()
00> 
00> <debug> nrf_dfu_serial_uart: serial_dfu_transport_init() completed
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> app: Enter main loop
00> 
00> <debug> app: timer_stop (0x20000020)
00> 
00> <debug> app: time<info> app: Inside main
00> 
00> <debug> app: In nrf_bootloader_init
00> 
00> <debug> nrf_dfu_settings: Calling nrf_dfu_settings_init()...
00> 
00> <debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
00> 
00> <debug> nrf_dfu_settings: Using settings page.
00> 
00> <debug> nrf_dfu_settings: Copying forbidden parts from backup page.

BR,

Lurn