I've written a DFU client in python. I'm trying to add the ability to restart a failed DFU without having to resend the whole file. I can see that the init packet is saved, because when I send the "create init object" packet [06 01] after a failed DFU attempt, the response contains the init packet's size and CRC. I've seen a link [1] which describes the general process, but I'm not sure I'm performing it correctly. After getting back the correct length and CRC in the init object create response, I send the execute object packet, expecting to get back a response indicating that there have already been some application objects created and stored. However, I always get back a packet indicating no bytes and no crc [60 06 01 00 10 00 00 00 00 00 00 00 00 00 00].
How do I continue a DFU from where it was before it failed?