Looking for 6303 documentation

[rob]

Hi,

I am starting on reversing a subaru ECU that uses the 6303 uP. I am completely new to the 6800 type series of controllers so I have a nice steep learning curve ahead of me. I have been searching the web for info and found a few links in this thread;

viewtopic.php?f=2&t=417

Unfortunately, all the links are dead. Does anybody have copies of the datasheet and instruction set details that they can forward to me? Better yet, are there any adventurous souls willing to help take a crack at the bin? I have access to IDA and have played around with it a little, starting at the interrupt vector tables. However I haven't gotten very far.

Any pointers or advice would be much appreciated.

-Rob
rob.files @ gmail.com

[Eric]

Is this what you're looking for ?

http://datasheets.chipdb.org/Hitachi/6303/


I also may be able to help you with the dissassembly

[rob]

Thanks Eric. Yep that's what I was looking for. I had a datasheet that seemed to have every other 6303 variant but the HD63B03YCP.

I will send you a PM about getting the binary to you to look at.

I have looked a bit closer at my initial attempt with IDA and also output from DASMx. The run through the interrupt vectors lead to a bit of a dead end at an indexed based jump call, like this;

FCA2 : 6E 00 "n " jmp $00,x

Obviously there a bunch of calls ahead of it manipulating the value that eventually ends up in the index reg. I need to figure out how to manually track what gets shoved into X. Some time with a simulator should help.

Any advice on how to work through this would be appreciated.

-Rob

Is this what you're looking for ?

http://datasheets.chipdb.org/Hitachi/6303/


I also may be able to help you with the dissassembly