[avrdude-dev] Add CRC to transfers?

[Gary Spivey]

We are using a version of the arduino bootloader. As far as we can tell,
the program data is sent via avrdude to the arduino bootloader and there
is no validation of the data that is coming across the comms link. When
the process is completed, there is a validation of what is in the flash,
however, we are beginning to believe that this is not sufficient. 

 

We are seeing few and random events where our bootloader is being
overwritten - it appears that the address might be getting corrupted in
the transfer, and the STK500 program is destroying our bootloader.

 

So - we were wondering about the possibility of modifying both the
bootloader and avrdude to do a CRC check on each and every
element/packet that comes across the comms link BEFORE acting upon it.
Before we start on this venture, we thought it wise to seek the advice
of this group on the best method to begin such an effort. (As in, do we
just hack the STK500.c code, or is there a better, more modular
approach)? Or, are we just nuts?

 

Any guidance would be greatly appreciated.

 

-Gary