The binary distribution of the firmware works, but I'm having an incredibly hard time modifying the firmware and making it work - I'm using IAR's 30 day trial. First off, trying to step though debugging fails miserably with the onboard USB interface (except for binary programming) -- I've connected a FET programmer that seems to work.
The problem occurs when a reta is called. Rather than jumping to the address at the top of the SP, it jumps to __program_start. The stack also seems to get mangled just after the start, the address on the top of the stack changes from 0x0000E0A0 to 0xE0A000009.
I've not experienced this before. Any idea what my issue is? Should I be checking out the errata?
Reza