RE: 6502 illegal opcodes

Some useful articles I was reading only this morning:

Why they exist : http://www.pagetable.com/?p=39

What they are: http://www.ffd2.com/fridge/docs/6502-NMOS.extra.opcodes 

Rob

-----Original Message-----
From: owner-cbm-hackers@musoftware.de
[mailto:owner-cbm-hackers@musoftware.de] On Behalf Of didier derny
Sent: 04 November 2011 17:02
To: cbm-hackers@musoftware.de
Subject: 6502 illegal opcodes

Hi,

In my cbm 8032 emulator I'm planning to have some support for illegal
opcodes

I saw 3 type of illegal opcodes

-  nop,   no visible action
-  hlt      kill the cpu
-  xxx     have an action

are they reliable from a 6502 to another  ?  (for example   mos vs 
rockwell vs synertek)
or between 6502, 6509, 6510 ?

I'm planning to support non and halt
and let the others not processed (my be in a futur version).

any idea  ?

--
didier






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