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Joppe Blondel
2026-04-01 17:39:05 +02:00
parent 8cce172c95
commit 435a96d203
6 changed files with 633 additions and 207 deletions
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6
video_dma.pio
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@@ -10,6 +10,7 @@
.define DATA_DELAY 4
.define LINE_IRQ 0
.define HSHIFT_DELAY 0
.define PUBLIC CLOCKS_PER_BIT DATA_DELAY + 2
.program cvsync
@@ -85,15 +86,16 @@ hsync_video:
; X = pixels_per_line - 1, preloaded once from C
; Each line:
; clear output
; reload Y from X
; wait for sync SM to raise LINE_IRQ
; apply a small extra delay for horizontal positioning
; reload Y from X
; shift out one bit per loop
.wrap_target
set pins, 0
mov y, x
wait 1 irq LINE_IRQ
irq clear LINE_IRQ
mov y, x
data_out:
out pins, 1 [DATA_DELAY]