From 702e19c25d69c4ada62edcdf6d17a6fe6e7b6df3 Mon Sep 17 00:00:00 2001
From: Steven Hugg <hugg@fasterlight.com>
Date: Sun, 20 Oct 2019 11:53:10 -0500
Subject: [PATCH] atari7800: added presets

---
 presets/atari7800/generic8x16.s | 518 ++++++++++++++++++++++++++++++++
 presets/atari7800/scroll.c      | 177 +++++++++++
 src/platform/atari7800.ts       |   1 +
 3 files changed, 696 insertions(+)
 create mode 100644 presets/atari7800/generic8x16.s
 create mode 100644 presets/atari7800/scroll.c

diff --git a/presets/atari7800/generic8x16.s b/presets/atari7800/generic8x16.s
new file mode 100644
index 00000000..380dd5ef
--- /dev/null
+++ b/presets/atari7800/generic8x16.s
@@ -0,0 +1,518 @@
+
+;;{w:8,h:16,bpp:2,count:128,brev:1,flip:1,remap:[0,8,9,10,11,1,2,3,4,5,6,7]};;
+.segment "CHR1"
+
+.byte $aa,$aa,$55,$55,$cc,$cc,$99,$99
+.byte $a0,$a0,$50,$50,$f5,$f5,$fa,$fa
+.byte $00,$00,$00,$00,$0a,$a8,$00,$00
+.byte $00,$00,$00,$00,$0a,$80,$0a,$00
+.byte $2a,$a8,$0a,$a8,$2a,$00,$0a,$a8
+.byte $0a,$a8,$2a,$2a,$2a,$2a,$0a,$a8
+.byte $2a,$a0,$0a,$a0,$2a,$00,$2a,$a0
+.byte $0a,$a0,$2a,$a8,$2a,$a8,$0a,$a0
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$00,$00,$0f
+.byte $03,$00,$00,$03,$c0,$03,$0f,$f0
+.byte $55,$aa,$66,$9a,$ff,$ff,$ff,$ff
+.byte $00,$03,$80,$00,$00,$00,$00,$00
+.byte $00,$55,$00,$00,$00,$05,$50,$00
+.byte $00,$00,$00,$00,$00,$55,$00,$00
+.byte $55,$55,$aa,$aa,$99,$99,$cc,$cc
+.byte $50,$50,$a0,$a0,$fa,$fa,$f5,$f5
+.byte $00,$00,$00,$00,$00,$00,$0a,$a8
+.byte $00,$00,$00,$00,$0a,$00,$0a,$80
+.byte $0a,$a8,$2a,$a8,$0a,$a8,$2a,$00
+.byte $2a,$2a,$0a,$a8,$0a,$a8,$2a,$2a
+.byte $0a,$a0,$2a,$a0,$2a,$a0,$2a,$00
+.byte $2a,$a8,$0a,$a0,$0a,$a0,$2a,$a8
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$03,$c0,$00,$00,$0f,$00,$00
+.byte $00,$03,$03,$00,$0f,$f0,$c0,$03
+.byte $66,$9a,$55,$aa,$ff,$ff,$ff,$ff
+.byte $80,$00,$00,$03,$00,$00,$00,$00
+.byte $00,$00,$00,$55,$50,$00,$00,$05
+.byte $00,$00,$00,$00,$00,$00,$00,$55
+.byte $aa,$aa,$55,$55,$33,$33,$66,$66
+.byte $0a,$0a,$05,$05,$5f,$5f,$af,$af
+.byte $00,$00,$0a,$a0,$25,$98,$00,$00
+.byte $00,$00,$02,$80,$05,$80,$06,$80
+.byte $15,$5a,$25,$5a,$16,$00,$25,$5a
+.byte $25,$5a,$16,$96,$16,$16,$25,$5a
+.byte $15,$68,$25,$68,$16,$00,$15,$68
+.byte $25,$68,$16,$58,$16,$58,$25,$68
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$00,$00,$f0
+.byte $03,$00,$00,$03,$30,$0c,$30,$0c
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+.byte $38,$07,$60,$1c,$00,$00,$00,$00
+.byte $00,$54,$54,$00,$10,$05,$40,$00
+.byte $10,$00,$2a,$50,$00,$55,$00,$00
+.byte $55,$55,$aa,$aa,$66,$66,$33,$33
+.byte $05,$05,$0a,$0a,$af,$af,$5f,$5f
+.byte $0a,$a0,$00,$00,$00,$00,$25,$98
+.byte $02,$80,$00,$00,$06,$80,$05,$80
+.byte $25,$5a,$15,$5a,$25,$5a,$16,$00
+.byte $16,$96,$25,$5a,$25,$5a,$16,$16
+.byte $25,$68,$15,$68,$15,$68,$16,$00
+.byte $16,$58,$25,$68,$25,$68,$16,$58
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$03,$c0,$00,$00,$f0,$00,$00
+.byte $00,$03,$03,$00,$30,$0c,$30,$0c
+.byte $77,$7e,$7d,$96,$65,$97,$e6,$59
+.byte $60,$1c,$38,$07,$00,$00,$00,$00
+.byte $54,$00,$00,$54,$40,$00,$10,$05
+.byte $2a,$50,$10,$00,$00,$00,$00,$55
+.byte $aa,$aa,$55,$55,$cc,$cc,$99,$99
+.byte $a0,$a0,$50,$50,$f5,$f5,$fa,$fa
+.byte $00,$00,$26,$68,$1a,$68,$00,$00
+.byte $0a,$a8,$01,$80,$05,$80,$05,$80
+.byte $16,$16,$16,$16,$16,$00,$16,$16
+.byte $16,$16,$16,$58,$16,$96,$16,$16
+.byte $16,$58,$16,$58,$16,$a0,$0a,$58
+.byte $16,$58,$15,$60,$16,$58,$16,$58
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$00,$0f,$00
+.byte $0c,$00,$00,$0c,$0c,$30,$c0,$03
+.byte $7d,$96,$f5,$5d,$e6,$59,$65,$97
+.byte $1d,$9f,$5a,$78,$00,$03,$c0,$00
+.byte $00,$a8,$50,$00,$16,$8a,$80,$00
+.byte $16,$a8,$aa,$50,$00,$96,$00,$00
+.byte $55,$55,$aa,$aa,$99,$99,$cc,$cc
+.byte $50,$50,$a0,$a0,$fa,$fa,$f5,$f5
+.byte $26,$68,$00,$00,$00,$00,$1a,$68
+.byte $01,$80,$0a,$a8,$05,$80,$05,$80
+.byte $16,$16,$16,$16,$16,$16,$16,$00
+.byte $16,$58,$16,$16,$16,$16,$16,$96
+.byte $16,$58,$16,$58,$0a,$58,$16,$a0
+.byte $15,$60,$16,$58,$16,$58,$16,$58
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$03,$c0,$00,$0f,$00,$00,$00
+.byte $00,$0c,$0c,$00,$c0,$03,$0c,$30
+.byte $f5,$5d,$7d,$96,$65,$97,$e6,$59
+.byte $5a,$78,$1d,$9f,$c0,$00,$00,$03
+.byte $50,$00,$00,$a8,$80,$00,$16,$8a
+.byte $aa,$50,$16,$a8,$00,$00,$00,$96
+.byte $aa,$aa,$55,$55,$33,$33,$66,$66
+.byte $0a,$0a,$05,$05,$5f,$5f,$af,$af
+.byte $00,$00,$15,$58,$19,$58,$00,$00
+.byte $05,$58,$29,$a8,$00,$00,$01,$a0
+.byte $16,$96,$16,$00,$16,$a0,$16,$96
+.byte $16,$16,$15,$60,$16,$56,$16,$16
+.byte $16,$58,$16,$a8,$15,$60,$25,$58
+.byte $00,$58,$15,$a0,$16,$58,$16,$58
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$00,$f0,$00
+.byte $0c,$00,$00,$0c,$03,$c0,$c0,$03
+.byte $55,$aa,$7d,$5e,$ea,$aa,$aa,$ab
+.byte $0e,$aa,$aa,$90,$00,$0e,$b0,$00
+.byte $00,$fa,$a0,$00,$06,$aa,$a0,$00
+.byte $16,$aa,$aa,$50,$00,$aa,$95,$00
+.byte $55,$55,$aa,$aa,$66,$66,$33,$33
+.byte $05,$05,$0a,$0a,$af,$af,$5f,$5f
+.byte $15,$58,$00,$00,$00,$00,$19,$58
+.byte $29,$a8,$05,$58,$01,$a0,$00,$00
+.byte $16,$00,$16,$96,$16,$96,$16,$a0
+.byte $15,$60,$16,$16,$16,$16,$16,$56
+.byte $16,$a8,$16,$58,$25,$58,$15,$60
+.byte $15,$a0,$00,$58,$16,$58,$16,$58
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$03,$c0,$00,$f0,$00,$00,$00
+.byte $00,$0c,$0c,$00,$c0,$03,$03,$c0
+.byte $7d,$5e,$55,$aa,$aa,$ab,$ea,$aa
+.byte $aa,$90,$0e,$aa,$b0,$00,$00,$0e
+.byte $a0,$00,$00,$fa,$a0,$00,$06,$aa
+.byte $aa,$50,$16,$aa,$95,$00,$00,$aa
+.byte $aa,$aa,$55,$55,$cc,$cc,$99,$99
+.byte $a0,$a0,$50,$50,$f5,$f5,$fa,$fa
+.byte $0a,$a0,$26,$68,$25,$a0,$28,$00
+.byte $09,$68,$15,$58,$00,$00,$01,$60
+.byte $15,$5a,$16,$00,$15,$60,$16,$56
+.byte $00,$16,$15,$a0,$15,$56,$16,$16
+.byte $16,$58,$16,$58,$16,$a8,$16,$58
+.byte $00,$58,$15,$68,$16,$58,$16,$58
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$0f,$00,$00
+.byte $30,$00,$00,$30,$03,$c0,$c0,$03
+.byte $aa,$55,$fd,$56,$ff,$ff,$ff,$ff
+.byte $06,$69,$a6,$a0,$00,$35,$ec,$00
+.byte $01,$fa,$ac,$00,$0f,$95,$50,$00
+.byte $16,$aa,$a0,$10,$00,$aa,$aa,$80
+.byte $55,$55,$aa,$aa,$99,$99,$cc,$cc
+.byte $50,$50,$a0,$a0,$fa,$fa,$f5,$f5
+.byte $26,$68,$0a,$a0,$28,$00,$25,$a0
+.byte $15,$58,$09,$68,$01,$60,$00,$00
+.byte $16,$00,$15,$5a,$16,$56,$15,$60
+.byte $15,$a0,$00,$16,$16,$16,$15,$56
+.byte $16,$58,$16,$58,$16,$58,$16,$a8
+.byte $15,$68,$00,$58,$16,$58,$16,$58
+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $00,$03,$c0,$00,$00,$00,$00,$0f
+.byte $00,$30,$30,$00,$c0,$03,$03,$c0
+.byte $fd,$56,$aa,$55,$ff,$ff,$ff,$ff
+.byte $a6,$a0,$06,$69,$ec,$00,$00,$35
+.byte $ac,$00,$01,$fa,$50,$00,$0f,$95
+.byte $a0,$10,$16,$aa,$aa,$80,$00,$aa
+.byte $aa,$aa,$55,$55,$33,$33,$66,$66
+.byte $0a,$0a,$05,$05,$5f,$5f,$af,$af
+.byte $06,$60,$15,$58,$1a,$60,$1a,$00
+.byte $05,$58,$01,$80,$00,$00,$00,$68
+.byte $16,$16,$16,$2a,$16,$00,$16,$2a
+.byte $00,$16,$15,$68,$15,$56,$16,$16
+.byte $15,$60,$05,$60,$16,$58,$05,$58
+.byte $00,$a8,$16,$58,$15,$60,$05,$60
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$00,$f0,$00,$00
+.byte $30,$00,$00,$30,$0c,$30,$c0,$03
+.byte $96,$7d,$df,$55,$e6,$59,$66,$ab
+.byte $0a,$db,$6d,$a0,$00,$d5,$7b,$00
+.byte $01,$55,$5c,$00,$0f,$55,$57,$c0
+.byte $3c,$55,$55,$00,$01,$55,$5a,$80
+.byte $55,$55,$aa,$aa,$66,$66,$33,$33
+.byte $05,$05,$0a,$0a,$af,$af,$5f,$5f
+.byte $15,$58,$06,$60,$1a,$00,$1a,$60
+.byte $01,$80,$05,$58,$00,$68,$00,$00
+.byte $16,$2a,$16,$16,$16,$2a,$16,$00
+.byte $15,$68,$00,$16,$16,$16,$15,$56
+.byte $05,$60,$15,$60,$05,$58,$16,$58
+.byte $16,$58,$00,$a8,$05,$60,$15,$60
+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $00,$03,$c0,$00,$00,$00,$00,$f0
+.byte $00,$30,$30,$00,$c0,$03,$0c,$30
+.byte $df,$55,$96,$7d,$66,$ab,$e6,$59
+.byte $6d,$a0,$0a,$db,$7b,$00,$00,$d5
+.byte $5c,$00,$01,$55,$57,$c0,$0f,$55
+.byte $55,$00,$3c,$55,$5a,$80,$01,$55
+.byte $aa,$aa,$55,$55,$cc,$cc,$99,$99
+.byte $a0,$a0,$50,$50,$f5,$f5,$fa,$fa
+.byte $06,$60,$06,$60,$05,$80,$06,$00
+.byte $00,$00,$01,$80,$00,$00,$00,$58
+.byte $16,$96,$16,$96,$16,$aa,$16,$96
+.byte $00,$16,$16,$5a,$15,$96,$16,$96
+.byte $16,$00,$00,$00,$05,$60,$00,$00
+.byte $00,$58,$16,$00,$00,$00,$00,$00
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
+.byte $c0,$00,$00,$03,$0f,$00,$00,$00
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+.byte $96,$7d,$d7,$d6,$e6,$59,$67,$fb
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+.byte $01,$55,$50,$00,$01,$55,$57,$c0
+.byte $35,$55,$55,$40,$05,$55,$55,$40
+.byte $55,$55,$aa,$aa,$99,$99,$cc,$cc
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+.byte $06,$60,$06,$60,$06,$00,$05,$80
+.byte $01,$80,$00,$00,$00,$58,$00,$00
+.byte $16,$96,$16,$96,$16,$96,$16,$aa
+.byte $16,$5a,$00,$16,$16,$96,$15,$96
+.byte $00,$00,$16,$00,$00,$00,$05,$60
+.byte $16,$00,$00,$58,$00,$00,$00,$00
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+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $00,$03,$c0,$00,$00,$00,$0f,$00
+.byte $00,$c0,$c0,$00,$30,$0c,$30,$0c
+.byte $d7,$d6,$96,$7d,$67,$fb,$e6,$59
+.byte $aa,$98,$26,$aa,$5e,$c0,$03,$55
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+.byte $55,$40,$35,$55,$55,$40,$05,$55
+.byte $aa,$aa,$55,$55,$33,$33,$66,$66
+.byte $0a,$0a,$05,$05,$5f,$5f,$af,$af
+.byte $06,$60,$00,$00,$00,$00,$06,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$18
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+.byte $00,$16,$16,$16,$16,$16,$05,$58
+.byte $16,$00,$00,$00,$00,$00,$00,$00
+.byte $00,$00,$16,$00,$00,$00,$00,$00
+.byte $00,$ff,$ff,$ff,$00,$ff,$ff,$ff
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+.byte $c0,$00,$00,$c0,$c0,$03,$0f,$f0
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+.byte $96,$6a,$a6,$96,$0d,$55,$57,$b0
+.byte $00,$55,$50,$00,$02,$bf,$f0,$00
+.byte $05,$55,$51,$f0,$15,$55,$55,$40
+.byte $55,$55,$aa,$aa,$66,$66,$33,$33
+.byte $05,$05,$0a,$0a,$af,$af,$5f,$5f
+.byte $00,$00,$06,$60,$06,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$18,$00,$00
+.byte $05,$58,$15,$58,$05,$58,$15,$56
+.byte $16,$16,$00,$16,$05,$58,$16,$16
+.byte $00,$00,$16,$00,$00,$00,$00,$00
+.byte $16,$00,$00,$00,$00,$00,$00,$00
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+.byte $ff,$ff,$00,$ff,$ff,$ff,$00,$ff
+.byte $00,$03,$c0,$00,$00,$00,$f0,$00
+.byte $00,$c0,$c0,$00,$0f,$f0,$c0,$03
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+.byte $50,$00,$00,$55,$f0,$00,$02,$bf
+.byte $51,$f0,$05,$55,$55,$40,$15,$55
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+.byte $0a,$a8,$2a,$2a,$2a,$a0,$2a,$aa
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+.byte $00,$00,$0a,$a8,$0a,$a8,$0a,$a8
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+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$ff,$ff,$f0,$00,$00,$00
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+.byte $02,$bf,$f0,$00,$00,$bf,$fc,$00
+.byte $01,$7f,$f0,$f0,$16,$aa,$aa,$90
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+.byte $ee,$ee,$dd,$dd,$a5,$a5,$f0,$f0
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+.byte $2a,$00,$00,$a8,$00,$00,$2a,$00
+.byte $2a,$2a,$0a,$a8,$2a,$aa,$2a,$a0
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+.byte $0a,$a8,$00,$00,$0a,$a8,$0a,$a8
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+.byte $00,$c0,$c0,$00,$00,$03,$c0,$00
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+.byte $ad,$bf,$fe,$da,$55,$ec,$35,$55
+.byte $f0,$00,$02,$bf,$fc,$00,$00,$bf
+.byte $f0,$f0,$01,$7f,$aa,$90,$16,$aa
+.byte $00,$00,$ff,$ff,$22,$22,$11,$11
+.byte $77,$77,$bb,$bb,$0f,$0f,$5a,$5a
+.byte $00,$00,$05,$80,$29,$a8,$28,$a8
+.byte $02,$58,$16,$80,$16,$80,$00,$00
+.byte $25,$58,$16,$16,$15,$68,$15,$56
+.byte $16,$16,$15,$56,$15,$56,$58,$16
+.byte $00,$00,$25,$98,$25,$58,$25,$58
+.byte $16,$58,$01,$60,$01,$60,$16,$16
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+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$00,$00,$0f,$00,$00,$00
+.byte $c0,$00,$00,$c0,$30,$00,$00,$0c
+.byte $5a,$d5,$99,$aa,$ea,$aa,$aa,$ab
+.byte $1e,$aa,$aa,$b4,$35,$55,$55,$ec
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+.byte $00,$bf,$fc,$00,$0f,$aa,$aa,$50
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+.byte $16,$16,$25,$58,$15,$56,$15,$68
+.byte $15,$56,$16,$16,$58,$16,$15,$56
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+.byte $01,$60,$16,$58,$16,$16,$01,$60
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+.byte $00,$00,$ff,$ff,$88,$88,$44,$44
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+.byte $00,$00,$0a,$80,$15,$58,$1a,$58
+.byte $09,$60,$05,$a0,$05,$80,$00,$00
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+.byte $16,$16,$01,$60,$16,$00,$58,$16
+.byte $00,$00,$1a,$58,$16,$58,$16,$a8
+.byte $16,$58,$01,$60,$01,$60,$16,$96
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$00,$00,$00,$f0,$00,$00
+.byte $30,$00,$00,$30,$0c,$00,$00,$30
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+.byte $06,$69,$a6,$90,$37,$55,$5d,$6c
+.byte $0a,$ff,$ef,$00,$02,$fb,$ec,$00
+.byte $0a,$ff,$ef,$00,$0a,$aa,$aa,$a0
+.byte $ff,$ff,$00,$00,$44,$44,$88,$88
+.byte $ee,$ee,$dd,$dd,$a5,$a5,$f0,$f0
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+.byte $05,$a0,$09,$60,$00,$00,$05,$80
+.byte $16,$16,$1a,$a8,$16,$00,$16,$5a
+.byte $01,$60,$16,$16,$58,$16,$16,$00
+.byte $1a,$58,$00,$00,$16,$a8,$16,$58
+.byte $01,$60,$16,$58,$16,$96,$01,$60
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$00,$00,$00,$00,$00,$f0
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+.byte $95,$5a,$56,$f7,$ff,$ff,$ff,$ff
+.byte $a6,$90,$06,$69,$5d,$6c,$37,$55
+.byte $ef,$00,$0a,$ff,$ec,$00,$02,$fb
+.byte $ef,$00,$0a,$ff,$aa,$a0,$0a,$aa
+.byte $00,$00,$ff,$ff,$22,$22,$11,$11
+.byte $77,$77,$bb,$bb,$0f,$0f,$5a,$5a
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+.byte $00,$00,$05,$58,$16,$58,$15,$58
+.byte $16,$58,$01,$60,$01,$60,$19,$96
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$00,$00,$00,$0f,$00,$00
+.byte $30,$00,$00,$30,$03,$00,$00,$c0
+.byte $aa,$aa,$95,$9a,$e6,$59,$65,$97
+.byte $06,$db,$6d,$a0,$37,$d7,$df,$6c
+.byte $02,$fb,$ec,$00,$02,$aa,$aa,$00
+.byte $02,$fb,$ec,$00,$02,$aa,$aa,$90
+.byte $ff,$ff,$00,$00,$11,$11,$22,$22
+.byte $bb,$bb,$77,$77,$5a,$5a,$0f,$0f
+.byte $05,$80,$00,$00,$06,$98,$09,$98
+.byte $01,$60,$05,$80,$0a,$a8,$05,$80
+.byte $16,$96,$19,$58,$16,$aa,$16,$16
+.byte $01,$60,$16,$96,$5a,$96,$16,$00
+.byte $05,$58,$00,$00,$15,$58,$16,$58
+.byte $01,$60,$16,$58,$19,$96,$01,$60
+.byte $00,$00,$00,$00,$ff,$00,$ff,$00
+.byte $00,$ff,$00,$ff,$ff,$ff,$ff,$ff
+.byte $00,$00,$00,$00,$00,$00,$00,$0f
+.byte $00,$30,$30,$00,$00,$c0,$03,$00
+.byte $95,$9a,$aa,$aa,$65,$97,$e6,$59
+.byte $6d,$a0,$06,$db,$df,$6c,$37,$d7
+.byte $ec,$00,$02,$fb,$aa,$00,$02,$aa
+.byte $ec,$00,$02,$fb,$aa,$90,$02,$aa
+.byte $00,$00,$ff,$ff,$88,$88,$44,$44
+.byte $dd,$dd,$ee,$ee,$f0,$f0,$a5,$a5
+.byte $00,$00,$05,$80,$05,$58,$29,$a0
+.byte $05,$80,$01,$60,$00,$00,$05,$58
+.byte $19,$98,$15,$56,$16,$16,$15,$56
+.byte $15,$56,$01,$60,$16,$00,$59,$96
+.byte $02,$80,$0a,$58,$16,$58,$16,$98
+.byte $16,$58,$01,$60,$01,$60,$15,$56
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$00,$00,$00,$00,$f0,$00
+.byte $0c,$00,$00,$0c,$00,$c0,$03,$00
+.byte $59,$aa,$95,$56,$36,$59,$65,$9c
+.byte $0e,$aa,$aa,$90,$0d,$5c,$35,$b0
+.byte $02,$aa,$aa,$00,$00,$aa,$aa,$80
+.byte $02,$aa,$aa,$00,$02,$aa,$aa,$90
+.byte $ff,$ff,$00,$00,$44,$44,$88,$88
+.byte $ee,$ee,$dd,$dd,$a5,$a5,$f0,$f0
+.byte $05,$80,$00,$00,$29,$a0,$05,$58
+.byte $01,$60,$05,$80,$05,$58,$00,$00
+.byte $15,$56,$19,$98,$15,$56,$16,$16
+.byte $01,$60,$15,$56,$59,$96,$16,$00
+.byte $0a,$58,$02,$80,$16,$98,$16,$58
+.byte $01,$60,$16,$58,$15,$56,$01,$60
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $00,$00,$00,$00,$f0,$00,$00,$00
+.byte $00,$0c,$0c,$00,$03,$00,$00,$c0
+.byte $95,$56,$59,$aa,$65,$9c,$36,$59
+.byte $aa,$90,$0e,$aa,$35,$b0,$0d,$5c
+.byte $aa,$00,$02,$aa,$aa,$80,$00,$aa
+.byte $aa,$00,$02,$aa,$aa,$90,$02,$aa
+.byte $00,$00,$ff,$ff,$22,$22,$11,$11
+.byte $77,$77,$bb,$bb,$0f,$0f,$5a,$5a
+.byte $00,$00,$05,$a0,$06,$6a,$1a,$68
+.byte $05,$a0,$09,$60,$00,$00,$00,$00
+.byte $19,$58,$16,$16,$16,$96,$16,$00
+.byte $16,$16,$01,$60,$16,$00,$59,$96
+.byte $09,$80,$05,$60,$05,$58,$05,$60
+.byte $15,$60,$02,$a0,$01,$60,$16,$58
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$00,$00,$00,$00,$0f,$00
+.byte $0c,$00,$00,$0c,$00,$30,$0c,$00
+.byte $d5,$5a,$9d,$5a,$3a,$59,$65,$ac
+.byte $2f,$5f,$59,$f8,$03,$f0,$0f,$c0
+.byte $00,$aa,$aa,$80,$02,$2a,$a0,$80
+.byte $00,$aa,$aa,$80,$00,$aa,$aa,$c0
+.byte $ff,$ff,$00,$00,$11,$11,$22,$22
+.byte $bb,$bb,$77,$77,$5a,$5a,$0f,$0f
+.byte $05,$a0,$00,$00,$1a,$68,$06,$6a
+.byte $09,$60,$05,$a0,$00,$00,$00,$00
+.byte $16,$16,$19,$58,$16,$00,$16,$96
+.byte $01,$60,$16,$16,$59,$96,$16,$00
+.byte $05,$60,$09,$80,$05,$60,$05,$58
+.byte $02,$a0,$15,$60,$16,$58,$01,$60
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $00,$00,$00,$00,$0f,$00,$00,$00
+.byte $00,$0c,$0c,$00,$0c,$00,$00,$30
+.byte $9d,$5a,$d5,$5a,$65,$ac,$3a,$59
+.byte $59,$f8,$2f,$5f,$0f,$c0,$03,$f0
+.byte $aa,$80,$00,$aa,$a0,$80,$02,$2a
+.byte $aa,$80,$00,$aa,$aa,$c0,$00,$aa
+.byte $00,$00,$ff,$ff,$88,$88,$44,$44
+.byte $dd,$dd,$ee,$ee,$f0,$f0,$a5,$a5
+.byte $00,$00,$05,$60,$05,$56,$16,$18
+.byte $01,$68,$25,$80,$00,$00,$00,$00
+.byte $1a,$98,$16,$96,$16,$58,$16,$aa
+.byte $16,$16,$29,$6a,$16,$00,$55,$56
+.byte $06,$00,$00,$00,$00,$58,$00,$00
+.byte $16,$00,$01,$60,$09,$60,$00,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$f0
+.byte $03,$00,$00,$03,$00,$0c,$30,$00
+.byte $f7,$56,$95,$56,$0f,$aa,$aa,$f0
+.byte $34,$07,$60,$1c,$00,$00,$00,$00
+.byte $02,$2a,$a0,$80,$00,$00,$00,$00
+.byte $02,$2a,$a0,$80,$02,$2a,$ab,$c0
+.byte $ff,$ff,$00,$00,$44,$44,$88,$88
+.byte $ee,$ee,$dd,$dd,$a5,$a5,$f0,$f0
+.byte $05,$60,$00,$00,$16,$18,$05,$56
+.byte $25,$80,$01,$68,$00,$00,$00,$00
+.byte $16,$96,$1a,$98,$16,$aa,$16,$58
+.byte $29,$6a,$16,$16,$55,$56,$16,$00
+.byte $00,$00,$06,$00,$00,$00,$00,$58
+.byte $01,$60,$16,$00,$00,$00,$09,$60
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$f0,$00,$00
+.byte $00,$03,$03,$00,$30,$00,$00,$0c
+.byte $95,$56,$f7,$56,$aa,$f0,$0f,$aa
+.byte $60,$1c,$34,$07,$00,$00,$00,$00
+.byte $a0,$80,$02,$2a,$00,$00,$00,$00
+.byte $a0,$80,$02,$2a,$ab,$c0,$02,$2a
+.byte $00,$00,$ff,$ff,$22,$22,$11,$11
+.byte $77,$77,$bb,$bb,$0f,$0f,$5a,$5a
+.byte $00,$00,$05,$60,$00,$60,$00,$00
+.byte $00,$58,$16,$00,$00,$00,$00,$00
+.byte $05,$60,$05,$58,$15,$60,$15,$56
+.byte $16,$16,$15,$56,$16,$00,$56,$58
+.byte $06,$00,$00,$00,$00,$58,$00,$00
+.byte $16,$00,$00,$00,$05,$60,$00,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $00,$00,$ff,$00,$00,$00,$ff,$00
+.byte $ff,$ff,$00,$00,$00,$00,$00,$0f
+.byte $03,$00,$00,$03,$00,$03,$c0,$00
+.byte $aa,$aa,$aa,$aa,$00,$ff,$ff,$00
+.byte $00,$03,$80,$00,$00,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$00
+.byte $ff,$ff,$00,$00,$11,$11,$22,$22
+.byte $bb,$bb,$77,$77,$5a,$5a,$0f,$0f
+.byte $05,$60,$00,$00,$00,$00,$00,$60
+.byte $16,$00,$00,$58,$00,$00,$00,$00
+.byte $05,$58,$05,$60,$15,$56,$15,$60
+.byte $15,$56,$16,$16,$56,$58,$16,$00
+.byte $00,$00,$06,$00,$00,$00,$00,$58
+.byte $00,$00,$16,$00,$00,$00,$05,$60
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $ff,$00,$00,$00,$ff,$00,$00,$00
+.byte $00,$00,$ff,$ff,$00,$0f,$00,$00
+.byte $00,$03,$03,$00,$c0,$00,$00,$03
+.byte $aa,$aa,$aa,$aa,$ff,$00,$00,$ff
+.byte $80,$00,$00,$03,$00,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$00
+.byte $00,$00,$00,$00,$00,$00,$00,$00
+
+;; 4096 bytes, 4 colors
diff --git a/presets/atari7800/scroll.c b/presets/atari7800/scroll.c
new file mode 100644
index 00000000..db87d487
--- /dev/null
+++ b/presets/atari7800/scroll.c
@@ -0,0 +1,177 @@
+
+#include "atari7800.h"
+
+#include <string.h>
+
+//#link "chr_font.s"
+
+//#link "generic8x16.s"
+
+#define DLL_FLAGS DLL_H16
+#define SLOTHEIGHT 16
+#define SLOTSIZE 32
+#define DOUBLEBUFFER
+#define DLSAVE
+
+#ifdef DOUBLEBUFFER
+#define NUMSLOTS 32
+byte slot0 = 0;
+#else
+#define NUMSLOTS 16
+const byte slot0 = 0;
+#endif
+
+
+DLLEntry DLL[NUMSLOTS];
+
+byte DL[NUMSLOTS][SLOTSIZE];
+byte DL_len[NUMSLOTS];
+
+#ifdef DLSAVE
+byte DL_save[NUMSLOTS];
+#endif
+
+void dll_set_addr(const void* dpp) {
+  MARIA.DPPH = (word)dpp>>8;
+  MARIA.DPPL = (byte)dpp;
+}
+
+void dll_clear() {
+  byte i;
+  for (i=slot0; i<slot0+16; i++) {
+    DL_len[i] = 0;
+    DL[i][1] = 0;
+  }
+}
+
+#ifdef DLSAVE
+void dll_save() {
+  memcpy(DL_save, DL_len, sizeof(DL_save));
+}
+
+void dll_restore() {
+  byte i;
+  memcpy(DL_len, DL_save, sizeof(DL_save));
+  for (i=0; i<NUMSLOTS; i++) {
+    DL[i][DL_len[i]+1] = 0;
+  }
+}
+#endif
+
+#ifdef DOUBLEBUFFER
+void dll_swap() {
+  slot0 ^= 16;
+  if (!slot0) {
+    dll_set_addr(DLL+16);
+  } else {
+    dll_set_addr(DLL);
+  }
+}
+
+void dll_set_scroll(byte y) {
+  static byte oldslot = 0;
+  byte slot = y / SLOTHEIGHT;
+  byte offset = 15 - (y & 15);
+  DLL[oldslot].offset_flags = DLL_FLAGS | (SLOTHEIGHT-1);
+  DLL[slot].offset_flags = DLL_FLAGS | offset;
+  dll_set_addr(DLL + slot);
+  oldslot = slot;
+}
+#endif
+
+void* dll_alloc(byte slot, byte len) {
+  byte dlofs;
+  slot &= NUMSLOTS-1;
+  dlofs = DL_len[slot];
+  DL_len[slot] += len;
+  DL[slot][dlofs+len+1] = 0;
+  return &DL[slot][dlofs];
+}
+
+void dll_add_sprite(word addr, byte x, byte y, byte wpal) {
+  byte slot = (y / SLOTHEIGHT) | slot0;
+  register DL4Entry* dl = (DL4Entry*) dll_alloc(slot, 4);
+  dl->data_lo = (byte)addr;
+  dl->data_hi = (byte)(addr>>8) + (y & 15);
+  dl->xpos = x;
+  dl->width_pal = wpal;
+  if (y & 15) {
+    DL4Entry* dl2 = (DL4Entry*) dll_alloc(slot+1, 4);
+    *dl2 = *dl;
+    dl2->data_hi -= SLOTHEIGHT;
+  }
+}
+
+void dll_add_string(const char* str, byte x, byte y, byte wpal) {
+  byte slot = (y / SLOTHEIGHT) | slot0;
+  register DL5Entry* dl = (DL5Entry*) dll_alloc(slot, 5);
+  dl->data_lo = (byte)str;
+  dl->data_hi = (word)str>>8;
+  dl->flags = DL5_INDIRECT;
+  dl->width_pal = wpal;
+  dl->xpos = x;
+}
+
+void dll_setup() {
+  byte i;
+  byte* dlptr = &DL[0][0];
+  register DLLEntry *dll = &DLL[0];
+  for (i=0; i<NUMSLOTS; i++) {
+    dll->offset_flags = DLL_FLAGS | (SLOTHEIGHT-1);
+    dll->dl_hi = (word)dlptr>>8;
+    dll->dl_lo = (byte)dlptr;
+    dlptr += sizeof(DL[0]);
+    dll++;
+  }
+  dll_clear();
+#ifdef DOUBLEBUFFER
+  dll_swap();
+  dll_clear();
+  dll_swap();
+#endif
+#ifdef DLSAVE
+  memset(DL_save, 0, sizeof(DL_save));
+#endif
+}
+
+char* hello = "\2\4\6\0\220\222\102";
+
+void main() {
+  byte i;
+  byte y = 0;
+
+  dll_setup();
+  
+  // activate DMA
+  MARIA.CHARBASE = 0x80;
+  MARIA.P0C1 = 0x8f;
+  MARIA.P0C2 = 0x4f;
+  MARIA.P0C3 = 0x1f;
+  MARIA.P1C1 = 0x34;
+  MARIA.P1C2 = 0x28;
+  MARIA.P1C3 = 0x1f;
+  MARIA.BACKGRND = 0;
+  dll_set_addr(DLL);
+  MARIA.CTRL = CTRL_DMA_ON | CTRL_DBLBYTE | CTRL_160AB;
+
+  dll_clear();
+  dll_add_string(hello, y+32, 32, DL_WP(8,0));
+  for (i=0; i<8; i++) {
+    slot0 = 0;
+    dll_add_sprite(0xa068, i*4, i*33, DL_WP(4,1));
+    dll_add_sprite(0xa06c, i*8, i*25, DL_WP(4,1));
+    slot0 = 16;
+    dll_add_sprite(0xa068, i*4, i*32, DL_WP(4,1));
+    dll_add_sprite(0xa06c, 128-i*8, i*24, DL_WP(4,1));
+  }
+  dll_save();
+
+  while (1) {
+    while ((MARIA.MSTAT & MSTAT_VBLANK) == 0) ;
+    dll_set_scroll(y);
+    dll_restore();
+    dll_add_sprite(0xa06c, y, y, DL_WP(4,1));
+    while ((MARIA.MSTAT & MSTAT_VBLANK) != 0) ;
+    y++;
+  }
+}
diff --git a/src/platform/atari7800.ts b/src/platform/atari7800.ts
index eb50c09e..aebaa750 100644
--- a/src/platform/atari7800.ts
+++ b/src/platform/atari7800.ts
@@ -6,6 +6,7 @@ import { PLATFORMS } from "../emu";
 var Atari7800_PRESETS = [
   {id:'sprites.dasm', name:'Sprites (ASM)'},
   {id:'wsync.c', name:'WSYNC'},
+  {id:'scroll.c', name:'Scrolling'},
 ];
 
 class Atari7800Platform extends Base6502MachinePlatform<Atari7800> implements Platform {