!LRDisabled = $7f9da1
!LPower = $7f9da2
!RPower = $7f9da3


!LRTimer = $1401
!scrolling = $13fd
!buttons = $17

!blank = #$fc
!L = #$15
!R = #$1b
!equals = #$77
!disabled = #$26
!exclaim = #$28

!BelowL = $0f1f
!BelowR = $0f24


; clear status bar
lda !blank
sta $0f03
sta $0f1e
sta $0f1f
sta $0f24
sta $0f1b
sta $0f1c

; display "L" and "R"
lda !L
sta $0f04
lda !R
sta $0f09


lda !LRDisabled
beq powers

stz !LRTimer
lda !disabled
sta !BelowL
sta !BelowR

powers:
lda !LPower
beq rpower

lda !exclaim
sta !BelowL

rpower:
lda !RPower
beq clearflags

lda !exclaim
sta !BelowR


clearflags:

lda #$00
sta !LRDisabled
sta !LPower
sta !RPower 


scrolling:
; if timer running or scrolling
lda !LRTimer
ora !scrolling
beq end

lda !buttons
and #$20   ; L
beq R

lda !equals
sta $0f1f

R:
lda !buttons
and #$10   ; R
beq end

lda !equals
sta $0f24

end:
rtl

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