mirror of
https://github.com/a2-4am/passport.git
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37 lines
894 B
Plaintext
37 lines
894 B
Plaintext
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; /!\ execution falls through from ChangeTrack
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;-------------------------------
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; ClearTSBuffer
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; clear the $1000 byte memory buffer
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; used to store the current track's data
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; in: none
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; out: Z = 1
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; X preserved
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; Y = 0
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; all other flags and registers clobbered
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;-------------------------------
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ClearTSBuffer
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lda #BASEPAGE
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ldx #$00
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ldy #$10
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; /!\ execution falls through here
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;-------------------------------
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; ClearMemory
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; in: A = source address (high)
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; X = value to set
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; Y = number of pages
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; out: Z = 1
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; X preserved
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; Y = 0
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; all other flags and registers clobbered
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;-------------------------------
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ClearMemory
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sta @dest+2
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@dest stx $FF00
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inc @dest+1
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bne @dest
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inc @dest+2
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dey
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bne @dest
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rts
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