Long delay after DFU completion SDK 12.1

RE: Long delay after DFU completion SDK 12.1

NickM — Tue, 06 Mar 2018 15:26:00 GMT

Thanks Vidar,

I am currently running all the SDK 12.1 code for the bootloader with no changes except for changing to the S332, and I am still seeing the issue.

I have started a private ticket.

Regards,

Nick

RE: Long delay after DFU completion SDK 12.1

Vidar Berg — Tue, 06 Mar 2018 12:54:22 GMT

Hi Nick,

The bootloader resets itself after receiving the new FW image, then on subsequent startup, it proceeds to active the new image. That is, replace old app image in bank 0, with new one, then update bootloader settings to validate the app (dual bank update). It sounds like the problem occurs in the activation stage while the image is being copied, but I don't see any reasons for why it would take >30 seconds to complete. Are you able to share your project so I can debug it on my side (you may create a private support ticket if you don't want to make it public)? Also, have you made other code changes that may be relevant, except for updating the SD API?

As a side note, the activation process should complete on following startup if interrupted by an unexpected reset, but it doesn't always work depending on when the reset occurs. The copy routine was made more robust in SDK 14.2.0, so you may consider back-porting it to SDK 12.1.0 if resets are likely to occur during activation.

RE: Long delay after DFU completion SDK 12.1

NickM — Mon, 05 Mar 2018 18:50:23 GMT

Hi Vidar,

I have tested with both our custom application, as well as the latest version of nRF toolbox, and both result in the same delay after the iPhone says the process is complete.

We have modified to use the S332 soft device.

In our situation, the user has the ability to do a power reset on the device. If this is done during that 30s delay, the device will end up being stuck in the bootloader. It seems like the bootloader is doing some verification or copying of the new application?

Regards,

Nick

RE: Long delay after DFU completion SDK 12.1

Vidar Berg — Mon, 05 Mar 2018 14:09:11 GMT

Hi,

Are you testing with a custom iOS app, or have you tried the same with nRF connect / nRF toolbox on ios? I was unable to reproduce this delay with the default bootloader from SDK 12.1.0 (testet DFU of APP).

There's no timeouts or other delays in SDK 12 that should cause the activation process to take 30 seconds as far as I can tell. DFU timeout was introduced SDK 14 as you already mentioned.

Regards,

Vidar

Update 3/8

I failed to reproduce this initially because I was doing single bank updates. Can now confirm that the activation process can take >10 seconds to complete for larger application images. The long delay is mainly caused by the flash operations needed for replacing the old application image in bank 0.

Attached is a slightly modified version of nrf_dfu_utils.c from SDK 12.1.0 that reduces the activation time (removed redundant page erases in copy routine) in addition to being more robust against unexpected resets. Changes were taken from from SDK 14.2.0

devzone.nordicsemi.com/.../nrf_5F00_dfu_5F00_utils.c