No response from nRF52820 when DFU is attempted again

RE: No response from nRF52820 when DFU is attempted again

Vidar Berg — Tue, 18 Oct 2022 11:55:40 GMT

Hi,

No problem. Yes, you are right, we currently do not have a fix for this available. It looks like it should be easy enough to fix, but I would be hesitant to make changes to critical changes to a critical part of the validation step without extensive testing and validation. I think it is safest to use the workaround for now. It should be possible to automate this recovery procedure without any user intervention.

RE: No response from nRF52820 when DFU is attempted again

Louis_263 — Tue, 18 Oct 2022 11:42:52 GMT

Hi Vidar,

Thanks for your fast answer 🙂 Currently there is probably no fix for this since no new SDK has come out yet, right?

RE: No response from nRF52820 when DFU is attempted again

Vidar Berg — Tue, 18 Oct 2022 10:35:57 GMT

Louis_263 , this is a known limitation, unfortunately. From the SDK release notes:

** DFU **

- NRFFOETT-2579: If the transfer is aborted when transferring a SoftDevice to a device
with no SoftDevice present (using sd-req = 0), the device can erroneously think that the SoftDevice
was transferred correctly. On smaller devices there could be no room
to transfer the SoftDevice again.
Workaround: Transfer any application with sd-req set to 0.
The application must be at least 3 pages (0x3000 bytes) long.
The application will overwrite the SoftDevice, allowing it to be retransferred.

In other words, to allow the SD update to be attempted again, you have to prepare a dummy app update which can overwrite the Softdevice first.

RE: No response from nRF52820 when DFU is attempted again

Louis_263 — Mon, 17 Oct 2022 09:52:31 GMT

My device is also in DFU mode but when I restart the DFU, then after a certain point no response comes from the nrf52820. Have you ever tested a SD+App DFU? As I described it in the original post

As I said, the DFU itself works. But when I cancel it manually and restart it, it no longer works. At the beginning, data is also transferred, but at some point there is no longer a response from the nRF. As can be seen in the logs in the original post, I think the bytes from the softdevices are also written to the wrong place in the flash memory (0x27000, but this is the beginning of my application). Normally the bytes should be written from address 0x1000. For these reasons, I think this may be a bug.

This is the log of the DFU, after I cancelled the the previous DFU manually while the softdevice is being updated:

devzone.nordicsemi.com/.../dfu_5F00_log_5F00_cancel_2D00_in_2D00_sd_2D00_dfu.txt

This is the log of the DFU, after I cancelled the the previous DFU manually while the app is being updated:

devzone.nordicsemi.com/.../dfu_5F00_log_5F00_cancel_2D00_in_2D00_app_2D00_dfu.txt

Vidar Berg Can you help out, maybe?

RE: No response from nRF52820 when DFU is attempted again

saurabh — Mon, 17 Oct 2022 09:44:28 GMT

i checked when device mode on dfu then i power off and then again connect it is show me on dfu mode

but i used nrf52832 module

RE: No response from nRF52820 when DFU is attempted again

Louis_263 — Mon, 17 Oct 2022 09:19:09 GMT

It also works for me if I don't cancel the DFU manually. For me, it's about simulating an error case where the DFU terminates for some reason in the later product and you have to restart the DFU via remote. If I abort the DFU while the softdevice is being updated, and restart the DFU afterwards, then it won't work anymore. I also use nrfutil version 6.1.7.

Maybe you could test if it works for you. So during the first part of the DFU (Softdevice DFU) disconnect the nRF from power and then restart the DFU again.

RE: No response from nRF52820 when DFU is attempted again

saurabh — Mon, 17 Oct 2022 08:21:54 GMT

the softdevice+application DFU worked with nrfutil version 6.1.7.