summaryrefslogtreecommitdiff
path: root/home/copy2.asm
diff options
context:
space:
mode:
authorPikalaxALT <PikalaxALT@gmail.com>2016-01-29 18:36:31 -0500
committerPikalaxALT <PikalaxALT@gmail.com>2016-01-29 18:36:31 -0500
commit2bf93c5905319e9181f87b3f83cd3bce7b9feeca (patch)
tree3ebf17c8879e5d6243d81aac8f1c36eb226fac26 /home/copy2.asm
parented3f9395f6d45f6554ed9d9c49c41ea86a8e2447 (diff)
Import stuff from pokecrystal; diff gold and silver
Diffstat (limited to 'home/copy2.asm')
-rw-r--r--home/copy2.asm135
1 files changed, 135 insertions, 0 deletions
diff --git a/home/copy2.asm b/home/copy2.asm
new file mode 100644
index 00000000..538be572
--- /dev/null
+++ b/home/copy2.asm
@@ -0,0 +1,135 @@
+CopyBytes:: ; 0x3026
+; copy bc bytes from hl to de
+ inc b ; we bail the moment b hits 0, so include the last run
+ inc c ; same thing; include last byte
+ jr .HandleLoop
+.CopyByte
+ ld a, [hli]
+ ld [de], a
+ inc de
+.HandleLoop
+ dec c
+ jr nz, .CopyByte
+ dec b
+ jr nz, .CopyByte
+ ret
+
+SwapBytes:: ; 0x3034
+; swap bc bytes between hl and de
+.Loop
+ ; stash [hl] away on the stack
+ ld a, [hl]
+ push af
+
+ ; copy a byte from [de] to [hl]
+ ld a, [de]
+ ld [hli], a
+
+ ; retrieve the previous value of [hl]; put it in [de]
+ pop af
+ ld [de], a
+ inc de
+
+ ; handle loop stuff
+ dec bc
+ ld a, b
+ or c
+ jr nz, .Loop
+ ret
+
+ByteFill:: ; 0x3041
+; fill bc bytes with the value of a, starting at hl
+ inc b ; we bail the moment b hits 0, so include the last run
+ inc c ; same thing; include last byte
+ jr .HandleLoop
+.PutByte
+ ld [hli], a
+.HandleLoop
+ dec c
+ jr nz, .PutByte
+ dec b
+ jr nz, .PutByte
+ ret
+
+GetFarByte:: ; 0x304d
+; retrieve a single byte from a:hl, and return it in a.
+ ; bankswitch to new bank
+ ld [hBuffer], a
+ ld a, [hROMBank]
+ push af
+ ld a, [hBuffer]
+ rst Bankswitch
+
+ ; get byte from new bank
+ ld a, [hl]
+ ld [hBuffer], a
+
+ ; bankswitch to previous bank
+ pop af
+ rst Bankswitch
+
+ ; return retrieved value in a
+ ld a, [hBuffer]
+ ret
+
+GetFarHalfword:: ; 0x305d
+; retrieve a halfword from a:hl, and return it in hl.
+ ; bankswitch to new bank
+ ld [hBuffer], a
+ ld a, [hROMBank]
+ push af
+ ld a, [hBuffer]
+ rst Bankswitch
+
+ ; get halfword from new bank, put it in hl
+ ld a, [hli]
+ ld h, [hl]
+ ld l, a
+
+ ; bankswitch to previous bank and return
+ pop af
+ rst Bankswitch
+ ret
+; 0x306b
+
+FarCopyWRAM:: ; 306b
+ ld [hBuffer], a
+ ld a, [rSVBK]
+ push af
+ ld a, [hBuffer]
+ ld [rSVBK], a
+
+ call CopyBytes
+
+ pop af
+ ld [rSVBK], a
+ ret
+; 307b
+
+GetFarWRAMByte:: ; 307b
+ ld [hBuffer], a
+ ld a, [rSVBK]
+ push af
+ ld a, [hBuffer]
+ ld [rSVBK], a
+ ld a, [hl]
+ ld [hBuffer], a
+ pop af
+ ld [rSVBK], a
+ ld a, [hBuffer]
+ ret
+; 308d
+
+GetFarWRAMWord:: ; 308d
+ ld [hBuffer], a
+ ld a, [rSVBK]
+ push af
+ ld a, [hBuffer]
+ ld [rSVBK], a
+ ld a, [hli]
+ ld h, [hl]
+ ld l, a
+ pop af
+ ld [rSVBK], a
+ ret
+; 309d