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Upload literally everything from the pokecrystal16 expand-move-ID branch

home/copy.asm

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+CopyBytes::
+; 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::
+; 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::
+; 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::
+; retrieve a single byte from a:hl, and return it in a.
+	; bankswitch to new bank
+	ldh [hTempBank], a
+	ldh a, [hROMBank]
+	push af
+	ldh a, [hTempBank]
+	rst Bankswitch
+
+	; get byte from new bank
+	ld a, [hl]
+	ldh [hFarByte], a
+
+	; bankswitch to previous bank
+	pop af
+	rst Bankswitch
+
+	; return retrieved value in a
+	ldh a, [hFarByte]
+	ret
+
+GetFarWord::
+; retrieve a word from a:hl, and return it in hl.
+	; bankswitch to new bank
+	ldh [hTempBank], a
+	ldh a, [hROMBank]
+	push af
+	ldh a, [hTempBank]
+	rst Bankswitch
+
+	; get word 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
+
+FarCopyWRAM::
+	ldh [hTempBank], a
+	ldh a, [rSVBK]
+	push af
+	ldh a, [hTempBank]
+	ldh [rSVBK], a
+
+	call CopyBytes
+
+	pop af
+	ldh [rSVBK], a
+	ret
+
+GetFarWRAMByte::
+	ldh [hTempBank], a
+	ldh a, [rSVBK]
+	push af
+	ldh a, [hTempBank]
+	ldh [rSVBK], a
+	ld a, [hl]
+	ldh [hFarByte], a
+	pop af
+	ldh [rSVBK], a
+	ldh a, [hFarByte]
+	ret
+
+GetFarWRAMWord:: ; unreferenced
+	ldh [hTempBank], a
+	ldh a, [rSVBK]
+	push af
+	ldh a, [hTempBank]
+	ldh [rSVBK], a
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	pop af
+	ldh [rSVBK], a
+	ret