diff options
| -rwxr-xr-x | constants.asm | 2 | ||||
| -rw-r--r-- | gfx/option_menu/blank.png | bin | 0 -> 75 bytes | |||
| -rwxr-xr-x | hram.asm | 1 | ||||
| -rwxr-xr-x | main.asm | 88 |
4 files changed, 47 insertions, 44 deletions
diff --git a/constants.asm b/constants.asm index fd0fbcd..221ca01 100755 --- a/constants.asm +++ b/constants.asm @@ -1 +1,3 @@ +INCLUDE "hram.asm" + INCLUDE "constants/song_constants.asm" diff --git a/gfx/option_menu/blank.png b/gfx/option_menu/blank.png Binary files differnew file mode 100644 index 0000000..961db91 --- /dev/null +++ b/gfx/option_menu/blank.png diff --git a/hram.asm b/hram.asm new file mode 100755 index 0000000..419d2dd --- /dev/null +++ b/hram.asm @@ -0,0 +1 @@ +hLoadedROMBank EQU $FFF8 ; this is updated whenever the code switches ROM Banks @@ -65,7 +65,7 @@ Start: ; 0x150 ld a, $0 ld [$4000], a ; Set bits 5 and 6 of ROM Bank Number ld a, $1 - ld [$fff8], a + ld [hLoadedROMBank], a ld a, $1 ld [$6000], a ; Enable RAM Banking Mode ld a, $0 @@ -187,13 +187,13 @@ Func_532: ; 0x532 SwitchBank: ; 0x549 ; Switches to Bank in register a and jumps to hl. - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a ; Load Bank jp [hl] Func_54f: ; 0x54f ld e, a - ld a, [$fff8] ; currently-loaded Bank + ld a, [hLoadedROMBank] ; currently-loaded Bank cp e jr z, .asm_570 push af @@ -209,7 +209,7 @@ Func_54f: ; 0x54f ld d, [hl] ld [hl], $0 ld [$2000], a - ld [$fff8], a + ld [hLoadedROMBank], a ld [hl], d pop de pop hl @@ -339,72 +339,72 @@ LoadVideoData: ; 0x6a4 ld a, [hli] ld h, [hl] ld l, a -.asm_6ad +.loadItem ld a, [hli] ld c, a and [hl] - cp $ff + cp $ff ; two consecutive $ff bytes terminate the array ret z ld a, [hli] - ld b, a + ld b, a ; bc contains pointer to data to be loaded push hl push bc - ld a, [hli] + ld a, [hli] ; a contains bank of data to be loaded ld e, [hl] inc hl - ld d, [hl] + ld d, [hl] ; de contains destination address for data inc hl ld c, [hl] inc hl - ld b, [hl] - inc hl + ld b, [hl] ; bc contains last word of data struct + inc hl ; this is a wasted instruction pop hl call Func_6cb pop hl ld bc, $0005 add hl, bc - jr .asm_6ad + jr .loadItem Func_6cb: ; 0x6cb srl b rr c - jp c, Func_6fd + jp c, Func_6fd ; if lowest bit of bc is set jp Func_6d5 ; This jumps to the next instruction... Strange. Func_6d5: ; 0x6d5 - ld [$fffa], a - ld a, [$fff8] + ld [$fffa], a ; save bank of data to be loaded + ld a, [hLoadedROMBank] push af - ld a, [$fffa] - ld [$fff8], a - ld [$2000], a + ld a, [$fffa] ; a contains bank of data to be loaded + ld [hLoadedROMBank], a + ld [$2000], a ; switch bank to the bank of data to be loaded srl b rr c rl a - and $1 - ld [$ff4f], a -.asm_6eb + and $1 ; checks bit 1 of the last word in the data struct + ld [$ff4f], a ; set VRAM Bank +.copyByte ld a, [hli] ld [de], a inc de dec bc ld a, c - or b - jr nz, .asm_6eb + or b ; does bc = 0? + jr nz, .copyByte xor a - ld [$ff4f], a + ld [$ff4f], a ; set VRAM Bank to Bank 0 pop af - ld [$fff8], a - ld [$2000], a + ld [hLoadedROMBank], a + ld [$2000], a ; reload the previous ROM Bank ret Func_6fd: ; 0x6fd - ld [$fffa], a - ld a, [$fff8] + ld [$fffa], a ; save bank of data to be loaded + ld a, [hLoadedROMBank] push af - ld a, [$fffa] - ld [$fff8], a - ld [$2000], a + ld a, [$fffa] ; a contains bank of data to be loaded + ld [hLoadedROMBank], a + ld [$2000], a ; switch bank to the bank of data to be loaded ld a, e bit 6, a jr nz, .asm_717 @@ -417,7 +417,7 @@ Func_6fd: ; 0x6fd call Func_724 .asm_71d pop af - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a ret @@ -427,14 +427,14 @@ Func_724: ; 0x724 set 7, a ld [de], a inc de -.asm_72b +.copyByte ld a, [hli] ld [de], a inc b dec c ret z bit 6, b - jr z, .asm_72b + jr z, .copyByte ret INCBIN "baserom.gbc",$735,$916 - $735 @@ -897,10 +897,10 @@ INCBIN "baserom.gbc",$d9d,$12a1 - $d9d Func_12a1: ; 0x12a1 ld [$fffa], a - ld a, [$fff8] + ld a, [hLoadedROMBank] push af ld a, [$fffa] - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a ld a, [hl] and $7 @@ -943,7 +943,7 @@ Func_12a1: ; 0x12a1 jr .asm_12b5 .asm_12e5 pop af - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a ret @@ -1007,10 +1007,10 @@ Func_12f8: ; 0x12f8 Func_1353: ; 0x1353 ld [$fffa], a - ld a, [$fff8] + ld a, [hLoadedROMBank] push af ld a, [$fffa] - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a push af push hl @@ -1048,7 +1048,7 @@ Func_1353: ; 0x1353 ld a, [$ff9e] ld [$ff40], a pop af - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a ret @@ -1246,21 +1246,21 @@ Func_2043: ; 0x2043 ld d, [hl] inc bc nop - ld a, [$fff8] + ld a, [hLoadedROMBank] push af ld a, $2 - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a call $4d17 ; todo jr c, .asm_2084 pop af - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a and a ret .asm_2084 pop af - ld [$fff8], a + ld [hLoadedROMBank], a ld [$2000], a scf ret |
