Checksum 0 after DFU init packet transfer

RE: Checksum 0 after DFU init packet transfer

Hung Bui — Wed, 14 Nov 2018 09:30:31 GMT

Thanks, good to know about the issue.

RE: Checksum 0 after DFU init packet transfer

raindeer — Tue, 13 Nov 2018 20:02:34 GMT

Realized the problem is a bug in the underlying ble lib and caused by this: https://github.com/aritchie/bluetoothle/issues/257

😩

RE: Checksum 0 after DFU init packet transfer

Hung Bui — Tue, 13 Nov 2018 09:49:05 GMT

Hi Raindeer,

There must be something wrong here. CRC must be calculated, unless there was no data received. I suspect somethign wrong with the write without response.

Could you capture a sniffer trace ? If we can compare what you send and what our DFU library sends and find the difference.

RE: Checksum 0 after DFU init packet transfer

raindeer — Mon, 12 Nov 2018 18:17:49 GMT

Hi!

Sorry for not being clear. Im implementing DFU in Xamarin (C#) using the ACR BLE lib (https://github.com/aritchie/bluetoothle)

I can use nRFConnect and also other implementations to do the DFU. So the problem is not on the device side.

The log is from my implementation running on an iPhone.

If followed the chart you link.
- I create the Command object with size 135 (01-01-87-00-00-00). Get 06-01-01 back as a notification.
- Transfer data to the packet characteristic in 20 bytes packets (WriteWithoutResponse)
- Then send 03 to get the checksum and get 60-03-01-00-00-00-00-00-00-00-00 (offset=0, CRC=0) back as if no data has been transfered.

If I ignore this problem and send Execute (04) then I get error code 08 back (Operation not permitted).

Somehow my data gets ignored. One question is this: if I send random data to the Command object and send 03 I still should get the CRC back, right? There is no validation of the init packet done before I actually execute it?

Thanks

RE: Checksum 0 after DFU init packet transfer

Hung Bui — Mon, 12 Nov 2018 16:00:34 GMT

Hi Raindeer,

Could you give us more information on:

- What do you mean by implement DFU ? Are you using our IOS-Pods-DFU-Library ?

- Can you use the nRFConnect or NRFToolbox app to do DFU of the same DFU package .zip file you used ?

- I'm not very familiar with the log you sent, from which side did you capture the log (phone or nRF5 ) ?

- Could you let me know where exactly in this sequence chart you have the issue ?

RE: Checksum 0 after DFU init packet transfer

raindeer — Mon, 12 Nov 2018 09:51:06 GMT

Still have not been able to figure this one out. It is as if no data is sent to the packet characteristic. But everything looks correct for the control point characteristic so cant understand how this could be the case. Ive looked at many other implementations and I seem to be doing the exact same thing..