Re: Lo-res/Double lo-res (was: Wacky Game idea)

[tsetse@helix.net (tsetse)]

In article <615340966wnr@klatch.demon.co.uk>, john@klatch.demon.co.uk wrote:

} listing I found some code which I think is redundant and was
} curious to know if anyone agreed with me (or if it was well known).
} 
} This is a snippet from the listing
} 
} GBASCALC  PHA
}           LSR A
}           AND #$03
}           ORA #$04
}           STA GBASH
}           PLA
}           AND #$18
}           BCC GBCALC
}           ADC #$7F
} GBCALC    STA GBASL
}           ASL A
}           ASL A
}           ORA GBASL
}           STA GBASL
}           RTS
>           LDA COLOR
>           CLC
>           ADC #$03
} SETCOL    AND #$0F
}           ...
} 
} From what I can tell, the LDA COLOR bit is never executed.  I know it's
} only 5 bytes, but does anyone know if it exists in later ROMs?

interesting. increment the colour by 3. now why the dickens does
that seem vaguely familiar? hmmm...

after looking some more, i see in the original apple ][ roms
that that routine is identified with the label 'NXTCOL' and
the comment 'INCREMENT COLOR BY 3'. now if i could just find 
an integer basic manual around here...

those same 5 bytes are also in my rom 1 gs. (at ff/f85f)

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