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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
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