[stella] About Stella's debugger asm

[seagtgruff at aol.com]

Don't forget?bankswitching schemes that?shift the TIA read/write addresses to a slightly higher spot in memory (e.g., beginning at $40), in which case a?user-defined?address between $00 and $3F is a definite possibility.

Michael


-----Original Message-----
From: Bob.Montgomery at thomsonreuters.com
To: stella at atari2600.org
Sent: Thu, 1 May 2008 12:33 pm
Subject: Re: [stella] About Stella's debugger asm



Hi,

>I guess I was talking about the following from the previous example:
>
>PF2                      000f              (R )
>MusicNtscDuration        000f              (R )
>
>What makes one of these hardcoded, while the other is user-defined?

Most user-defined equates in the range $00 through $7F would only be
used as immediate values; i.e.:
lda #MusicNtscDuration
or something similar, since they for sure aren't RAM.  So where there is
a conflict between a user-defined value and a TIA register, you could
always use user-defined equates for immediate values and always use TIA
registers otherwise, i.e., 
sta $0F ; this could be PF2 or MusicNtscDuration, since it isn't an
immediate value use PF2: sta PF2
and #$0F ; this could be PF2 or MusicNtscDuration, since it is an
immediate value use the user-defined value.

Seems like that would work.

-Bob

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