Talk:Programming with unofficial opcodes: Difference between revisions
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== Stability of ATX == | == Stability of ATX == | ||
[http://anyplatform.net/media/guides/cpus/65xx%20Processor%20Data.txt The reference I'm using] lists ATX as "unstable"; I made a point of leaving "unstable" instructions out of a reference for programmers. Furthermore, it states that its behavior might differ between machines. It cites two references agreeing with you but also cites [http://nesdev.parodius.com/extra_instructions.txt Adam Vardy's document], which calls the instruction "OAL", claims that it includes ORA #$EE as one of the steps, and further claims that different machines use different values instead of $EE. It might actually be ORA <line noise> AND #i TAX. --[[User:Tepples|Tepples]] 16:25, 8 February 2011 (UTC) | [http://anyplatform.net/media/guides/cpus/65xx%20Processor%20Data.txt The reference I'm using] lists ATX as "unstable"; I made a point of leaving "unstable" instructions out of a reference for programmers. Furthermore, it states that its behavior might differ between machines. It cites two references agreeing with you but also cites [http://nesdev.parodius.com/extra_instructions.txt Adam Vardy's document], which calls the instruction "OAL", claims that it includes ORA #$EE as one of the steps, and further claims that different machines use different values instead of $EE. It might actually be ORA <line noise> AND #i TAX, and predictable only if i = 0 (in which case it's no different from LAX #0). --[[User:Tepples|Tepples]] 16:25, 8 February 2011 (UTC) | ||
Revision as of 16:29, 8 February 2011
Stability of ATX
The reference I'm using lists ATX as "unstable"; I made a point of leaving "unstable" instructions out of a reference for programmers. Furthermore, it states that its behavior might differ between machines. It cites two references agreeing with you but also cites Adam Vardy's document, which calls the instruction "OAL", claims that it includes ORA #$EE as one of the steps, and further claims that different machines use different values instead of $EE. It might actually be ORA <line noise> AND #i TAX, and predictable only if i = 0 (in which case it's no different from LAX #0). --Tepples 16:25, 8 February 2011 (UTC)
