owLRControl:
LDA $0100
CMP #$0E
BEQ + : RTL : +
LDA $16
AND #$03
BEQ +
CMP #$01 : BEQ .right
REP #$20
LDA $1F17
SEC : SBC #$0010
STA $1F17
LSR A : STA $141F
SEP #$20
BRA +
.right
REP #$20
LDA $1F17
SEC : SBC #$FFF0
STA $1F17
LSR A : STA $141F
SEP #$20
+

; test
LDA $16
AND #$0C
BEQ +
CMP #$08 : BEQ .up
REP #$20
LDA $1F19
SEC : SBC #$FFF0
STA $1F19
LSR A : STA $1421
SEP #$20
BRA +
.up
REP #$20
LDA $1F19
SEC : SBC #$0010
STA $1F19
LSR A : STA $1421
SEP #$20
+
RTL

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