[Coco] HD63x09 Question

jdaggett at gate.net jdaggett at gate.net
Wed Jan 5 11:03:33 EST 2005


to the 6309 experts:

I recently obtained 4 HD63C09EP chips and was looking at doing a 
project with them. I did a Google search and found the original post 
to comp.sys.m6809 group by Hirotsugu Kakugawa. Between that 
memo and Chet Simpson's technical manual I have some needs to 
confirm what I suspect:

1) that the increased instruction set is available in either "emulated" 
or "native" modes and that 

2) the MULD and the DIVD and DIVQ instructions due signed math 
and not unsigned!

This seems odd as the MUL instrtuction of the 6809 is unsigned. IF 
the new math opcodes are indeed signed math then I will  have to 
do some extra manipulation since  I am doing unsigned math.


james



More information about the Coco mailing list