Post - Forum - Plus/4 World



	Home Search Games Tapes Covers Cheats Maps Software New Stuff Hall Of Fame HVTC Game Endings Solutions Remakes Publications Magazines Effects Top List Members Groups Features Plus/4 Encyclopedia Hardware Tools Options Forum Home Search Games Tapes Covers Cheats Maps Software New Stuff Hall Of Fame HVTC Game Endings Solutions Remakes Publications Magazines Effects Top List Members Groups Features Plus/4 Encyclopedia Hardware Tools Options Forum	Login

Forum Help

Post Your Message

Previous Messages

Posted By

SVS
on 2016-02-22
06:49:09

Re: 6502 code $x2

Thus they are so called KIL opcodes! Very interesting, thank you.

Posted By

gerliczer
on 2016-02-22
02:49:49

Re: 6502 code $x2

Thanks a lot, Doug. I wanted to recommend this article to SVS but I couldn't find it.

Posted By

Doug
on 2016-02-21
18:55:49

Re: 6502 code $x2

Hi,

Best article I've read on it: http://www.pagetable.com/?p=39

I used a lot of unlisted op codes in the past to obfuscate code. Some were like multibyte NOPs, which confused disassemblers! Others did 'odd' but useful stuff. This article gives a really good explanation of why.

Doug

Posted By

SVS
on 2016-02-20
13:52:56

6502 code $x2

Since ever I wondered why all the executing codes, of 6502 family, with "2" as second nibble are jamming the processor. For example: $02, $12, ... $82, $92 etc.
The only exception to this rule is $A2 (LDX).

Who know the mystery?