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mode7: play music at 25Hz

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sounds horrible for now
This commit is contained in:
Vince Weaver 2018-03-19 00:27:14 -04:00
parent 1de05f88b9
commit d935782bfd
1 changed files with 3 additions and 2 deletions
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5
mode7_demo/mode7_demo.s
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@ -74,14 +74,15 @@ mockingboard_setup:
sta $C40D ; IFR: 1100, enable interrupt on timer one oflow sta $C40D ; IFR: 1100, enable interrupt on timer one oflow
sta $C40E ; IER: 1100, enable timer one interrupt sta $C40E ; IER: 1100, enable timer one interrupt
lda #$E7 lda #$40
sta $C404 ; write into low-order latch sta $C404 ; write into low-order latch
lda #$4f lda #$9c
sta $C405 ; write into high-order latch, sta $C405 ; write into high-order latch,
; load both values into counter ; load both values into counter
; clear interrupt and start counting ; clear interrupt and start counting
; 4fe7 / 1e6 = .020s, 50Hz ; 4fe7 / 1e6 = .020s, 50Hz
; 9c40 / 1e6 = .040s, 25Hz
;============================ ;============================