DFU over BLE and USB

[MattyIce]

My current project has DFU enabled through the secure BLE bootloader and it works well. I would like to include the additional option of performing DFU over USB. Is it possible to combine the two functions into the same bootloader? Does Nordic have any sample code which does this?

Thanks

[ovrebekk]

Hi

It is possible to do, yes, but there is no example showing how to do it unfortunately. 

How are you planning to switch between the two bootloader transports?

Best regards
Torbjørn

[Anantha Keshava]

I have a similar requirement to use USB DFU in the factory, use background DFU over BLE in the field. Is there any pointer to achieve this?

I read that for background DFU, the Bootloader shouldn't initialize any of the transports however, I have the need to have these be initialized and then choose between a factory/RMA update vs. user/field update.

Appreciate any help.

Thanks and regards,

Ananth

[Hung Bui]

I don't think it's a problem having 2 transportation options in one DFU bootloader. Have you tried to combine them ? 

You can find in nrf_dfu_transports_init() all transports are initialized in the function. 

[Anantha Keshava]

Hung Bui said:

Have you tried to combine them ?

Hi Hung Bui,

I was able to build with both transports enabled in the SDK config. However, I find that on attempting to enter the DFU mode (button press during reset), I see that the board continuously keeps resetting instead of enumerating the USB and/or broadcasting BLE beacons.

[Anantha Keshava]

On debugging further, I find that the crash occurs in the nrf_dfu_transports_init while calling the
ret_val = trans->init_func(observer);

I checked both USB and BLE transports are registered correctly and the DFU_TRANS_SECTION_ITEM_COUNT returns 2 as expected.

[Hung Bui]

The trans->init_func() will call the init function registered by each transport layer. Could step in and check which error code is throwing out and the reason for that ? 

[Anantha Keshava]

Hi Hung Bui,

I stepped through and found the crash while performing ble_stack_init() in the ble_dfu_transport_init(). I can't step beyond sdh_state_observer_notify() in the nrf_sdh_enable_request() part of the ble_stack_init().