the documentation is a bit vague

[RG]

I'm implementing my own equivalent of hci_dfu_send_hex; There is not enough information in the documentation on how these packets are constructed. I found that the first packet (prep flash) sent by hci_dfu_send_hex to the bootloader has an ACK counter of 0x02, sequence of 0x01; the next (first data packet) has an ACK of 0x03 and a sequence of 0x02; also the data packet payload length seems to be 0x204; this includes the DFU packet field length ? (I assume); also the 8bit checksum field is still a mystery at this point; Does anyone have any information that is clearer....reverse engineering the structures is fun but time consuming. cheers Radu

[Ole Morten]

I think most of what you need to know should be covered by this question, so I suggest you take a look at my answer there. In general, I'd recommend to keep the Core spec ready when implementing this on your own. :-)

[RG]

Thanks Ole, got it working; solved the problem last night. best Radu