I've grabbed the Atmel bootloader, however it's been 20 years since I've worked with assembler so my understanding of it is limited.

However, from what you've said...


Could I create my own 'C' bootloader that has a custom 485 interface built in (which would allow me to use addressing to specify processors) and use a custom protocol to have a controller send the hex data, a bit at a time.

Could my bootloader then receive these packets, and store each one (after CRC checks) into the code flash memory until they are all received and then boot itself back into normal running?

I already have a 485 interface and protocol that is used during normal running of things. This allows the controller to speak to each of the 9 processors individually (by address) and use broadcasts. Could I just strip out this interface and use this as a foundation of the bootloader?

Is the bootloader, in essence, 'just another app' but limited to 2k, and triggered to run conditionally?


I know I've over simplified things here, but I'd rather get a firm grasp of things before I start delving into the more complex areas. It helps to ensure I understand what I'm doing :)