nRF52832 Serial DFU - Transfer Init Packet - No Response after "Execute Command"

[c.arndt]

Hi,

I am currently implementing the protocol for a serial DFU, following the instructions given here:

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v14.2.0%2Flib_dfu_transport_serial.html&cp=4_0_0_3_5_2_3.

The general flow I implemented is:

Get MTU (0x07) --> Select Command Object (0x06 0x01) --> Create Command Object (0x01 0x01)  --> Write up to MTU bytes of data (0x08 XX .... XX) --> Execute Command (0x04)

Up to "Execute Command" everything seems to work perfectly fine. The problem is, I do not get any response on the execute command - neither a "Response Execute Success" nor any failure. 

Do you have any idea, what I am doing wrong here?

Thanks,

Christian

[lesher]

Are you sending ALL of the .dat file Bytes before calling Execute?

[c.arndt]

Yes I do, I have a .dat file of size 135 Bytes. Wrapping it with "Write ID (0x08)" + Slip encoding I have a total size of 138 Bytes which I am transmitting via UART to nRF.

As far as I could see I have max MTU size of 33024 Bytes (is it possible that I am exchanging big endian with little endian?). However, even half of the MTU size means I can transfer .dat file completely at once.

Might here be some issue?

[c.arndt]

Okay I got some new information:

It was a good hint to ask whether really all bytes are transmitted via "Write" command.

I changed the interpretation of "Get MTU" response into little endian --> 0x00 0x81 --> resulting in 129 Bytes (before I interpreted as 0x81 0x00 --> 32k).

With "Create Command Object" I actually reserve the space I need for the .dat file (which is 135 Bytes). Is that enough or do I need to reserve space for the whole slip encoded message (in this case 141 bytes)?

However, I tried with creating 141 Bytes command object and now I do receive response for "Execute" command:

DFU ERROR OPCODE <0x4 0x8> OPERATION_NOT_PERMITTED

Now the question is, why is this operation not permitted?

(when I tried with creating 135 Bytes command object, again I do not receive any response after execute command)

[lesher]

For Create Command Object, use the non-slip-encoded size.
The best way to see what's happening is to see the bootloader's logs - RTT is built in to the examples.

Also, refer to this file for the host-side details: github.com/.../dfu_transport_serial.py

[c.arndt]

Actually I was trying some time to get RTT logs.. unfortunately after starting Segger RTT Logger I only get a screen saying "Searching for RTT Control Block"..

Any idea how I can enable RTT logging?

[c.arndt]

Okay I got some RTT logs:

<debug> app: Received get serial mtu
<debug> app: Sending Response: [0x7, 0x1]
<debug> nrf_dfu_flash: Initializing nrf_fstorage_nvmc backend.
<debug> app: Received get serial mtu
<debug> app: Sending Response: [0x7, 0x1]
<debug> app: Waiting for events
<debug> app: Received select object
<info> dfu_req_handling: Valid Command: NRF_DFU_OBJECT_OP_SELECT
<debug> app: Sending Response: [0x6, 0x1]
<debug> app: Received create object
<info> dfu_req_handling: Before OP create command
<info> dfu_req_handling: Valid Command Create
<debug> app: Sending Response: [0x1, 0x1]
<info> dfu_req_handling: Before OP write command
<info> dfu_req_handling: Before OP write command
<info> dfu_req_handling: Before OP write command
<debug> app: Received execute object
<info> dfu_req_handling: Before OP execute command
<info> dfu_req_handling: Valid command execute
<info> dfu_req_handling: PB: Init packet data len: 58
<info> dfu_req_handling: Handling signed command
<info> dfu_req_handling: Invalid signature type
<error> dfu_req_handling: Prevalidate failed!
<debug> app: Sending Response: [0x4, 0xB]
<debug> app: Received execute object
<info> dfu_req_handling: Before OP execute command
<info> dfu_req_handling: Valid command execute
<info> dfu_req_handling: PB: Init packet data len: 58
<info> dfu_req_handling: Handling signed command
<info> dfu_req_handling: Invalid signature type
<error> dfu_req_handling: Prevalidate failed!
<debug> app: Sending Response: [0x4, 0xB]

What do they tell you?