I’ve read a few articles on MCUBoot and your other articles on bootloaders. I’m interested in a bootloader that sets up its second slot (non-executing app image) in a remote memory location. This can be the on my PC connected to my target device, another MCU that can communicate with the target MCU (this is my case), or the cloud.
In my case, I will have a SPI interface to another MCU which has access to an external flash. The external flash (secondary slot) would contain the new image that would be used to update the target MCU. Using the simple erase and replace algorithm, I figured that the target MCU can update its on-chip flash with the image on the external flash via requests to the other MCU to retrieve and send over the SPI bus the new image one sector at a time. I have not seen any example code that can do this. Would you have any information on this?
Thanks