HCI DFU Packet Header Building

[PY]

I want to update the nordic device from another MCU with HCI DFU. I cannot figure out how to write the packet header. In the Nordic documentation, it is writen to read the Bluetooth Core Specification document but the header is actually not made on the same model :

Moreover, in examples I read, I don't know why the first Ack number and Seq number are not both 0 in the first Start Packet.

Thank you for your explanation.

[bjorn-spockeli]

Hi PHY,

I recommend that you take a look at the pc-nrfutil v0.5.2 implementation of Serial DFU, found here.

Specifically, see the dfu_transport_serial.py file found in the nordicsemi/dfu folder.

Best regards

Bjørn

[PY]

Hi Bjorn, Thank you for your answer. I'll take a look at this. Regards, PY