How to switch to bootloader when OTA?

RE: How to switch to bootloader when OTA?

Hung Bui — Tue, 27 Dec 2016 15:44:12 GMT

How would I test, Alice ? It simply works with both NRFToolbox and nRFConnect with the buttonless example in our SDK. You need to check and compare why it works when you test with NRFConnect and not when with nRFToolbox.

RE: How to switch to bootloader when OTA?

John — Tue, 27 Dec 2016 12:52:30 GMT

Hi Hung,it would reach the code where I write to GPREGRET when I use the nRFToolbox try to do DFU. Could you help to test it? Thanks.

RE: How to switch to bootloader when OTA?

Hung Bui — Tue, 27 Dec 2016 12:41:02 GMT

Hi Alice,

It's a little bit strange because both nRFConnect and nRFToolbox uses the same DFU library. You may want to capture a sniffer trace when you test with nRFToolbox, it could tell what when wrong.

You can also add a break point in the application code where you write to GPREGRET before you jump to bootloader, to see if it reach there when the nRFToolbox try to do DFU.

RE: How to switch to bootloader when OTA?

John — Tue, 27 Dec 2016 09:15:44 GMT

Hi Hung, now I can use nRF Connect in IOS to write the characteristic(write 0x01 value) to make it switch to bootloader. I do it as follow, in the ble_dfu_evt_handler function, I will write the GPREGRET register: case BLE_DFU_EVT_ENTERING_BOOTLOADER: sd_power_gpregret_set(0,0xB1); NVIC_SystemReset(); printf("Device is entering bootloader mode!\r\n"); break; Then in the bootloader, I will check the GPREGRET register in nrf_dfu_enter_check() function:

__WEAK bool nrf_dfu_enter_check(void)

{

	if(NRF_POWER->GPREGRET==0x01)	
	{	
		NRF_POWER->GPREGRET =0x00;		
		return true;
	}

if (nrf_gpio_pin_read(BOOTLOADER_BUTTON) == 0)
{
    return true;
}

if (s_dfu_settings.enter_buttonless_dfu == 1)
{
    s_dfu_settings.enter_buttonless_dfu = 0;
    (void)nrf_dfu_settings_write(NULL);
    return true;
}
return false;

}

After that, it will switch to bootloader and then update the fireware. However, the DFU app in the nRF Toolbox cann't make it switch to bootloader. If I want to use it to make it switch to bootloader, what should I do? Could I use the APP to do OTA?

RE: How to switch to bootloader when OTA?

John — Tue, 27 Dec 2016 08:43:00 GMT

No, this case hasn't been solved. link text I have read it and I test experimental_ble_app_buttonless_dfu example, it also cann't switch to bootloader.

RE: How to switch to bootloader when OTA?

Hung Bui — Tue, 27 Dec 2016 08:36:21 GMT

Hi Alice, I saw that you accepted the answer in the other case, could you confirm this case is also solved ?

RE: How to switch to bootloader when OTA?

John — Mon, 26 Dec 2016 08:31:58 GMT

Yes, I have program the bootloader. Only it switch to the bootloader mode so that I can do other things. I have known how to do if it switch to bootloader mode. I test experimental_ble_app_buttonless_dfu example, I meet the same probelm that it cann't switch to the bootloader mode. I can see the log information "Device is entering bootloader mode " and then it resets.

RE: How to switch to bootloader when OTA?

Hung Bui — Wed, 21 Dec 2016 09:42:11 GMT

Have you programmed the bootloader, Alice ? Please follow the instruction on how to use the bootloader example in the documentation.

RE: How to switch to bootloader when OTA?

John — Wed, 21 Dec 2016 09:36:28 GMT

Hi Hung, now I have added the write properties and use nRF connect APP in IOS to write it. I can see the log information "Device is entering bootloader mode " and then reset, but it doesn't switch to the bootloader mode. Could you tell me what problem would be? Thanks.

RE: How to switch to bootloader when OTA?

Hung Bui — Fri, 16 Dec 2016 13:12:39 GMT

Hi Alice, Please find the example in \examples\ble_peripheral\experimental_ble_app_buttonless_dfu\ instead.

Note that you would need to add the write properties as described here.