About the secure serial DFU for nRF52840 and nRF52832

[Alice]

Hi,

I'm using SDK13.0 with nRF52840. Now I'm doing the DFU by the UART through MCU. But we meet a big problem, MCU is hard to read the infomation in the .dat and .json file, so we want to just use the .bin file to do DFU.

I have seen the data on the UART interface as the attachment. It seems MCU must read the infomation in the .dat and .json file and then send to nRF52840, so that it could do DFU. What we want to do is not to do Transfer of an init packet, just do Initialization and the Transfer of a firmware image . As described link text

Could anyone tell me how to do for the bootloader project? Thanks.

PC.txt BLE.txt

[Hung Bui]

Hi Alice,

The MCU doesn't need to read the .json file. It just need to send the .dat (which is the binary of the init packet) and the .bin.

If you don't plan to send init packet, you will not be able to check for image size, CRC and signature when you receiving the image.

I would suggest you to try sending init packet, instead of modifying the bootloader to skip it.

If you want a very simple bootloader, you can go back to SDK v6.x where we don't require init packet, and the bootloader was pretty simpler.

[Hung Bui]

You would need to modify the bootloader in SDK v6.x to meet your need. I think it shouldn't be too difficult just some change in the flash size and softdevice API.

Do you have full control over the WIFI module, is there any MCU on it ? If there is, you should be able to program the chip to send init packet first and then send firmware image .