Search found 4 matches

by raejae
Fri Oct 03, 2008 12:57 pm
Forum: Programming
Topic: instruction logic reference?
Replies: 19
Views: 12530

I got home and thankfully the history on my other computer went back far enough for me to find it... for anybody that might be interested it is here:

http://homepage.ntlworld.com/cyborgsyst ... 2/6502.htm

And thanks for the links, Garth, much appreciated.
by raejae
Fri Oct 03, 2008 5:43 am
Forum: Programming
Topic: instruction logic reference?
Replies: 19
Views: 12530

instruction logic reference?

Hello all...

A couple of weeks ago I was browsing around at some sites with 6502 instruction information. I remember very vividly visiting a site that had each instruction, all of the opcodes and (here's the important part) a list of the logic steps for each instruction. I failed to bookmark the ...
by raejae
Sat Sep 20, 2008 9:51 pm
Forum: Programming
Topic: indexed addressing modes - signed?
Replies: 6
Views: 5659

That's exactly what I needed--thanks!
by raejae
Sat Sep 20, 2008 7:45 pm
Forum: Programming
Topic: indexed addressing modes - signed?
Replies: 6
Views: 5659

indexed addressing modes - signed?

Hello all,

I'm looking for a piece of information that I can't seem to find anywhere, therefore must be blatantly obvious and I'm missing it.

When using indexed addressing modes, is the index interpreted as signed or unsigned? (ie if I have the address $2000 and the index in the X register is $80 ...