RE: What happens after the final execute op code of the DFU?

Amanda Hsieh — Wed, 14 Apr 2021 07:13:54 GMT

The RTT log from using _debug example bootloader project can help. Also, see the Device Firmware Update process doc.

-Amanda H.

RE: What happens after the final execute op code of the DFU?

PF-JohnF — Fri, 09 Apr 2021 12:51:40 GMT

Thank you for your response

I used the command

nrfutil.exe pkg generate --app-boot-validation NO_VALIDATION --hw-version 52 --sd-req 0x101 --application-version 0xff --application APP2.hex --key-file ../priv.pem APP2.zip

to generate a .zip file without validation, and kept the old .zip file with validation and compared the power consumption of the two.

Here's the power consumption after the application hex file has finished transmitting:

With validation:

Without validation:

The first high power state in this graph is the crc/validation check. The power consumed without validation is about half of the power consumed when using validation during the validation step.

By commenting out or removing the validation check from the postvalidate function in nrf_dfu_validation, power usage is reduced even further.

I'm confused what happens after the crc check though, and I'm having a tough time to follow the execution path of the code after it leaves nrf_dfu_req_handler. I'm not sure if there is a lot of data being copied to another bank or is it possible that the high power is just caused when the device is reset, or maybe even something else entirely?

RE: What happens after the final execute op code of the DFU?

Amanda Hsieh — Thu, 08 Apr 2021 13:12:10 GMT

Hi John,

Could you try to generate the package with --app-boot-validation NO_VALIDATION (skip CRC) for comparison? Does it help?

-Amanda H.