MC6803U4 info?

[Daniel R. Henriksson]

Hi

I'm in the process of reverse-engineering a Weber/Marelli ECU (IAW048/01)
and i need to clarify some things about the CPU.
I know my questions are slightly off topic but you guys are my last shot.

Does anyone know the difference between the 6803C and the 6803U4?
After digging on the net i have found out that the 6803U4 has an
additional 64 bytes of onboard RAM at 0x40-0x7f. 
But i suspect there is some other differences, what about timer
capabilities, there is a new SFR at 0x18 that's supposedly a
timer control register, anyone know the specs. for that register?

If anyone has any additional information then please inform me!

Some of my findings can be viewed at:
http://www.ludd.luth.se/~rotax/

BR
 Daniel Henriksson
 rotax at ludd.luth.se