firmware update procedures differs in P&S and dslr cameras:
- for P&S cameras PS.FIR file containg binary module which is loaded by camera and this module performs update
- firmware file for dslrs contain only flash image and code of camera performs update
Yes, understand. BTW Powershots have even a capability to run external software if placed to the right directory (CF\DC97\MISC) - the .exe and short inf file and then it appears in camera menu.
I didn't analyzed 350D FW detailed but maybe there's similar posibility to run some scripts or binaries somewhere from CF. On the other side, if this feature exists probably someone would discoveredn it during the years.
Well so suppose the only way is to flash modified FW to run other code. I think this modification wouldn't be so large. I don't understand how VxWorks boots but may use some text initscripts which can then look for a file on CF. Once this works it will be no problem to delete the file from CF if anything goes wrong. If you think you can do this patch with a relative low risk I will test it. Then some memory dumper would be run to get whole memory contents. If you need I can give you 350D FW update (available on canon site) and decrypter (also available at yahoo canon group or so).
Does anybody make this experiment on any other DSLR?