nRF5340 single bank FOTA

[Tomasz K]

Hi,

I was evaluating FOTA on nRF5340 as possible upgrade to 52 series. All went good which I'm happy of.

However application size is limited roughly to half flash size remaining after subtracting space occupied by MCUboot and it's scratch area. If I understand correctly, MCUboot works similar to 52 series "Dual Bank" update, so both images have to fit in flash.

Question is: does the NCS and/or zephyr supports equivalent of "Single Bank" update (where new firmware overwrites old during download) or it's something that requires custom implementation? 

I know that it's possible to use external flash, but it takes precious PCB space, so ideally it will be not to use external memory.

Thanks for help

Tomasz

[Amanda Hsieh]

Hi Tomasz,

You could do serial dfu within the bootloader itself. Otherwise, it has to be "dual banked". To do DFU with UART on nRF Connect SDK you would need to use mcumgr and smpsvr and enable the serial recovery in the mcuboot (check some similar posts like this and this).

-Amanda H.