mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-11-22 14:33:51 +00:00
25 lines
671 B
C
25 lines
671 B
C
|
|
;-------------------------------------------------------
|
|
; Usage: TIMER_SETUP lines
|
|
; where lines is the number of scanlines to skip (> 2).
|
|
; The timer will be set so that it expires before this number
|
|
; of scanlines. A WSYNC will be done first.
|
|
|
|
MAC TIMER_SETUP
|
|
.lines SET {1}
|
|
lda #(((.lines-1)*76-14)/64)
|
|
sta WSYNC
|
|
sta TIM64T
|
|
ENDM
|
|
|
|
;-------------------------------------------------------
|
|
; Use with TIMER_SETUP to wait for timer to complete.
|
|
; You may want to do a WSYNC afterwards, since the timer
|
|
; is not accurate to the beginning/end of a scanline.
|
|
|
|
MAC TIMER_WAIT
|
|
.waittimer
|
|
lda INTIM
|
|
bne .waittimer
|
|
ENDM
|