[avr-gcc-list] r-engineering the JTAG-ICE protocol

[Karl Ran]

Hi there!

I'd like to know if anyone already started to reverse-engineer the
AVR-onchip-JTAG-ICE command-set on the newer Mega16++ AVRs.
If not, anyone knows the complexity of the ICE command-sets on the
microconrollers in general?

I realy wonder why Atmel put a big Mega163 in its JTAG-RS232 interface.

How hard can it be?
JTAG is synchronouns protocol, AFAIK. So it should be quite easy to
capture, right?

I'd guess the (binary) commands could look like these:
Set bp as/ds
Clr bp as/ds
read mem
write mem
read reg
write reg
set pc
read ICE-status
read adr-bus history
stop
start
..

Am I totaly on the wrong track here?

Any tips, infos, etc are welcome!

Karl




_________________________________________________________________
Send and receive Hotmail on your mobile device: http://mobile.msn.com

avr-gcc-list at http://avr1.org