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POKEY variable definitions / address mappings for $0450?


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Hi folks,


In moving my POKEY address from $4000 to $0450, I was curious if the equates below would change much (outside of the POKEY_START indicator I'm using):


; POKEY equates for the Atari 7800

        processor 6502

; Set our magic start
POKEY_START     equ     $0450

AUDF2   equ     POKEY_START+$00 ; extra audio channels and frequencies
AUDC2   equ     POKEY_START+$01
AUDF3   equ     POKEY_START+$02
AUDC3   equ     POKEY_START+$03
AUDF4   equ     POKEY_START+$04
AUDC4   equ     POKEY_START+$05
AUDF5   equ     POKEY_START+$06
AUDC5   equ     POKEY_START+$07
AUDCTL  equ     POKEY_START+$08 ; Audio Control
RANDOM  equ     POKEY_START+$0A ; Random number (read-only)
SKCTL   equ     POKEY_START+$0F ; Serial Port control


The file I'm using is way ancient; there's probably a better / newer / more portable header file out there with more usable variables than what I had from eons ago.  Any assistance would be appreciated.



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You'd just change the POKEY_START, and everything else would stay the same.


We haven't discovered any extra ram for variables or anything like that. I put together my own 7800.h file a while back when I first released 7800basic, and have tried to keep it up to date - though most of the additions are comments, since the hardware doesn't change. My pokey register equates are a bit non-standard, so if you use the header you'll likely want to substitute your own. (7800basic uses indirect access for pokey because XM was once going to be a thing, so a rom that might have used pokey@4000 could also use XM's pokey@450)

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