ref: 35f6b6e68c8c8a7d164f67e1ae452270a28ac3b7
dir: /home/copy.asm/
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