Merge pull request #35 from zohassadar/mmc3

Mmc3

Author: kirjavascript

build.sh

@@ -3,7 +3,7 @@
 compile_flags=()
 
 help () {
-    echo "Usage: $0 [-v] [-m <1|3>] [-a] [-s] [-k] [-h]"
+    echo "Usage: $0 [-v] [-m <1|3|4>] [-a] [-s] [-k] [-h]"
     echo "-v  verbose"
     echo "-m  mapper"
     echo "-a  faster aeppoz + press select to end game"
@@ -16,8 +16,8 @@ while getopts "vm:askh" flag; do
   case "${flag}" in
     v) set -x ;;
     m)
-        if ! [[ "${OPTARG}" =~ ^[13]$ ]]; then
-            echo "Valid INES_MAPPER (-m) options are 1 or 3"
+        if ! [[ "${OPTARG}" =~ ^[134]$ ]]; then
+            echo "Valid INES_MAPPER (-m) options are 1, 3 or 4"
             exit 1
         fi
         compile_flags+=("-D INES_MAPPER=${OPTARG}")

src/chr.asm

@@ -1,6 +1,6 @@
 .segment "CHR"
 
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
     .incbin "chr/title_menu_tileset.chr"
     .incbin "chr/game_tileset.chr"
     .incbin "chr/rocket_tileset.chr"

src/gamemode/gametypemenu/menu.asm

@@ -11,11 +11,16 @@ gameMode_gameTypeMenu:
         lda #0
         sta displayNextPiece
         RESET_MMC1
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
         ; switch to blank charmap
         ; (stops glitching when resetting)
         lda #$03
         jsr changeCHRBank1
+.endif
+.if INES_MAPPER = 4
+        ; Horizontal mirroring
+        lda #$1
+        sta MMC3_MIRRORING
 .endif
         lda #%10011 ; used to be $10 (enable horizontal mirroring)
         jsr setMMC1Control

src/gamemode/speedtest.asm

@@ -21,7 +21,7 @@ gameMode_speedTest:
         sta PPUADDR
         lda #$30
         sta PPUDATA
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
         lda #$01
         jsr changeCHRBank0
         lda #$01

src/gamemode/waitscreen.asm

@@ -6,7 +6,7 @@ waitScreenLoad:
         sta renderMode
         jsr updateAudioWaitForNmiAndDisablePpuRendering
         jsr disableNmi
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
         lda #$02
         jsr changeCHRBank0
         lda #$02

src/gamemodestate/initbackground.asm

@@ -1,7 +1,7 @@
 gameModeState_initGameBackground:
         jsr updateAudioWaitForNmiAndDisablePpuRendering
         jsr disableNmi
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
         lda #$01
         jsr changeCHRBank0
         lda #$01
@@ -47,6 +47,10 @@ gameModeState_initGameBackground:
         lda #%10011000
         sta PPUCTRL
         sta currentPpuCtrl
+.elseif INES_MAPPER = 4
+        ; Vertical mirroring (Prevents screen glitching)
+        lda #$0
+        sta MMC3_MIRRORING
 .endif
         jsr resetScroll
         jsr waitForVBlankAndEnableNmi

src/io.asm

@@ -46,6 +46,10 @@ MMC1_Control := $8000
 MMC1_CHR0   := $BFFF
 MMC1_CHR1   := $DFFF
 
+MMC3_BANK_SELECT := $8000
+MMC3_BANK_DATA := $8001
+MMC3_MIRRORING := $A000
+
 .macro RESET_MMC1
 .if INES_MAPPER = 1
         inc $8000 ; initRam

src/playstate/gameover_rocket.asm

@@ -76,7 +76,7 @@ sleep_gameplay:
 endingAnimation: ; rocket_screen
         jsr updateAudioWaitForNmiAndDisablePpuRendering
         jsr disableNmi
-.if INES_MAPPER = 1
+.if INES_MAPPER = 1 || INES_MAPPER = 4
         lda #$02
         jsr changeCHRBank0
         lda #$02

src/util/core.asm

@@ -311,6 +311,17 @@ changeCHRBank0:
         sta MMC1_CHR0
         lsr a
         sta MMC1_CHR0
+.elseif INES_MAPPER = 4
+        asl a
+        asl a
+        ldx #$00
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
+        inx
+        clc
+        adc #$02
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
 .endif
         rts
 
@@ -325,6 +336,27 @@ changeCHRBank1:
         sta MMC1_CHR1
         lsr a
         sta MMC1_CHR1
+.elseif INES_MAPPER = 4
+        asl a
+        asl a
+        ldx #$02
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
+        inx
+        clc
+        adc #$01
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
+        inx
+        clc
+        adc #$01
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
+        inx
+        clc
+        adc #$01
+        stx MMC3_BANK_SELECT
+        sta MMC3_BANK_DATA
 .endif
         rts
 
@@ -339,5 +371,16 @@ changePRGBank:
         sta MMC1_PRG
         lsr a
         sta MMC1_PRG
+.elseif INES_MAPPER = 4
+        asl     a
+        asl     a
+        ldx     #$06
+        stx     MMC3_BANK_SELECT
+        sta     MMC3_BANK_DATA
+        inx
+        clc
+        adc     #$01
+        stx     MMC3_BANK_SELECT
+        sta     MMC3_BANK_DATA
 .endif
         rts