DFU question - I wonder whether there is a way that BLE knows the device is upgrade its software

[PingISTL]

Dear support

I tried DFU OTA example here recently and it works for me and have a question to ask.

My application is a central app and host by my main MCU via UART interface, I wonder when device firmware is being updated by OTA, is there a way the app knows before it enters boot mode, so it can tell main MCU a message about that ?

Thank you!

Ping 

[PingISTL]

Hi, Hieu

Thank you for reply and spend time on it, it is not an easy one, I understand.

Initially I thought it can tell by connected as a peripheral role as the advertising function is only added for DFU purpose, but then it is possible that it can be connected for echo or something else but not upgrading firmware.

If firmware had an unexpected reboot - not initiated by host MCU, then it is probably a reboot following a DFU OTA, but that can only be told after the DFU happened.

That is all I can think of, I am not familiar with more deep insight into the protocols.

Regards!

Ping

[Hieu]

Hi Ping,

I found a few API that can help you. You can click the link to go to the header file with full documentation. Further below are an example usage from me and the log from my test.

• In <NCS Root>\zephyr\subsys\mgmt\mcumgr\lib\cmd\os_mgmt
  void os_mgmt_register_reset_evt_cb(os_mgmt_on_reset_evt_cb cb);
  Unfortunately this API is only available from NCS v2.0.0. Are you working on the same NCS v1.9.1 from your previous ticket...?
  
  
• In <NCS Root>\zephyr\subsys\mgmt\mcumgr\lib\cmd\img_mgmt
  void img_mgmt_register_callbacks(const struct img_mgmt_dfu_callbacks_t *cb_struct);

void test_dfu_started_cb(void) { printk("%s\n", __func__); }
void test_dfu_stopped_cb(void) { printk("%s\n", __func__); }
void test_dfu_pending_cb(void) { printk("%s\n", __func__); }
void test_dfu_confirmed_cb(void) { printk("%s\n", __func__); }

const struct img_mgmt_dfu_callbacks_t test_img_mgmt_dfu_callbacks = {
    .dfu_started_cb = &test_dfu_started_cb,
    .dfu_stopped_cb = &test_dfu_stopped_cb,
    .dfu_pending_cb = &test_dfu_pending_cb,
    .dfu_confirmed_cb = &test_dfu_confirmed_cb
};

int test_os_mgmt_on_reset_evt_cb(void) {
    printk("%s\n", __func__);
    return 0;
}

void main(void)
{
    [...]
    
    printk("build time: " __DATE__ " " __TIME__ "\n");

    os_mgmt_register_group();
    os_mgmt_register_reset_evt_cb(&test_os_mgmt_on_reset_evt_cb);
    img_mgmt_register_group();
    img_mgmt_register_callbacks(&test_img_mgmt_dfu_callbacks);
    smp_bt_register();
    
    [...]
}

*** Booting Zephyr OS build v3.0.99-ncs1-1  ***
I: Starting bootloader
I: Primary image: magic=good, swap_type=0x2, copy_done=0x1, image_ok=0x1
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Bootloader chainload address offset: 0xc000
I: Jumping to the first image slot
▒*** Booting Zephyr OS build v3.0.99-ncs1-1  ***
Starting Nordic UART service example
build time: Sep 21 2022 18:40:24
test_dfu_started_cb
test_dfu_pending_cb
test_os_mgmt_on_reset_evt_cb
*** Booting Zephyr OS build v3.0.99-ncs1-1  ***
I: Starting bootloader
I: Primary image: magic=good, swap_type=0x2, copy_done=0x1, image_ok=0x1
I: Secondary image: magic=good, swap_type=0x2, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: test
I: Starting swap using move algorithm.
I: Bootloader chainload address offset: 0xc000
I: Jumping to the first image slot
*** Booting Zephyr OS build v3.0.99-ncs1-1  ***
Starting Nordic UART service example
build timex: Sep 21 2022 17:18:35

As of now I haven't seen any API to interfere with the DFU process as suggested in this Q&A yet. However, is it enough for your current requirement yet?

Side note, I am out of office tomorrow, so unfortunately the earliest I can follow up will be Friday.

Best regards,

Hieu