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authorDaniel Harding <33dannye@gmail.com>2021-09-19 00:21:14 -0500
committerGitHub <noreply@github.com>2021-09-19 00:21:14 -0500
commitdf67aac83b466dadf5f74c881bf84dd9ef19bdfc (patch)
tree47501aced2d256052b8f78bc97328d5af5703add /src/home/copy.asm
parente4bce9b7ee5e89f8edfd921de2379f0fa06af206 (diff)
parent8dee6b7a11e85d6d4b9f8ec9fb9d53a499fd37dc (diff)
Merge pull request #110 from ElectroDeoxys/master
Split Home bank
Diffstat (limited to 'src/home/copy.asm')
-rw-r--r--src/home/copy.asm57
1 files changed, 57 insertions, 0 deletions
diff --git a/src/home/copy.asm b/src/home/copy.asm
new file mode 100644
index 0000000..8b21f90
--- /dev/null
+++ b/src/home/copy.asm
@@ -0,0 +1,57 @@
+; copy c bytes of data from hl to de, b times.
+; used to copy gfx data with c = TILE_SIZE
+CopyGfxData:
+ ld a, [wLCDC]
+ rla
+ jr nc, .next_tile
+.hblank_copy
+ push bc
+ push hl
+ push de
+ ld b, c
+ call JPHblankCopyDataHLtoDE
+ ld b, $0
+ pop hl
+ add hl, bc
+ ld e, l
+ ld d, h
+ pop hl
+ add hl, bc
+ pop bc
+ dec b
+ jr nz, .hblank_copy
+ ret
+.next_tile
+ push bc
+.copy_tile
+ ld a, [hli]
+ ld [de], a
+ inc de
+ dec c
+ jr nz, .copy_tile
+ pop bc
+ dec b
+ jr nz, .next_tile
+ ret
+
+; copy bc bytes from hl to de. preserves all registers except af
+CopyDataHLtoDE_SaveRegisters:
+ push hl
+ push de
+ push bc
+ call CopyDataHLtoDE
+ pop bc
+ pop de
+ pop hl
+ ret
+
+; copy bc bytes from hl to de
+CopyDataHLtoDE:
+ ld a, [hli]
+ ld [de], a
+ inc de
+ dec bc
+ ld a, c
+ or b
+ jr nz, CopyDataHLtoDE
+ ret