use 255 for auto detect

Author: zohassadar

build.js

@@ -6,7 +6,7 @@ const { spawnSync } = require('child_process');
 console.log('TetrisGYM buildscript');
 console.time('build');
 
-const mappers = [0, 1, 3, 4, 5];
+const mappers = [255, 1, 3, 4, 5];
 
 // options handling
 
@@ -43,7 +43,7 @@ console.log(`using ${nativeCC65 ? 'system' : 'wasm'} ca65/ld65`);
 
 // mapper options
 
-const mapper = args.find((d) => d.startsWith('-m'))?.slice(2) ?? 0;
+const mapper = args.find((d) => d.startsWith('-m'))?.slice(2) ?? 255;
 
 if (!mappers.includes(+mapper)) {
     console.error(

src/constants.asm

@@ -1,9 +1,7 @@
 .ifndef INES_MAPPER ; is set via ca65 flags
-INES_MAPPER := 0 ; supports 0 (autodetect 1/3), 1, 3, 4 and 5 (MMC1 / CNROM / MMC3 / MMC5)
+INES_MAPPER := 255 ; 1 (MMC1), 3 (CNROM), 4 (MMC3), 5 (MMC5),  and 255 (autodetect 1/3)
 .endif
 
-HAS_MMC = INES_MAPPER = 1 || INES_MAPPER = 4 || INES_MAPPER = 5
-
 .ifndef SAVE_HIGHSCORES
 SAVE_HIGHSCORES := 1
 .endif

src/header.asm

@@ -12,8 +12,8 @@
 INES_MIRROR = 0 ; 0 = horizontal mirroring, 1 = vertical mirroring (ignored in MMC1)
 INES_SRAM   = 1 ; 1 = battery backed SRAM at $6000-7FFF
 
-; Override INES_MAPPER for mode 0 (auto detect)
-.if INES_MAPPER = 0
+; Override INES_MAPPER for mode 255 (auto detect)
+.if INES_MAPPER = 255
     .if CNROM_OVERRIDE
     _INES_MAPPER = 3 ; Test CNROM on Emulator/Flashcart
     .else

src/io.asm

@@ -62,7 +62,7 @@ MMC5_CHR_BANK0 := $5123 ; 4kb page index
 MMC5_CHR_BANK1 := $5127
 
 .macro RESET_MMC1
-.if INES_MAPPER = 0 .or INES_MAPPER = 1
+.if INES_MAPPER = 1 .or INES_MAPPER = 255
 :       inc :-  ; increments inc ($aa), writing a negative value to prg
                 ; https://www.nesdev.org/wiki/MMC1#Reset
 .endif

src/main.asm

@@ -55,7 +55,7 @@ mainLoop:
 .include "util/menuthrottle.asm"
 .include "util/modetext.asm"
 .include "util/mapper.asm"
-.if INES_MAPPER = 0
+.if INES_MAPPER = 255
 .include "util/autodetect.asm"
 .endif
 

src/ram.asm

@@ -210,7 +210,7 @@ dasOnlyShiftDisabled: .res 1 ; $63A
 
 invisibleFlag: .res 1 ; $63B  ; 0 for normal mode, non-zero for Invisible playfield rendering.  Reset on game init and game over.
 
-mapperId: .res 1 ; $63C ; For INES_MAPPER 0 (autodetect).  0 = CNROM.  1 = MMC1.  
+mapperId: .res 1 ; $63C ; For INES_MAPPER 255 (autodetect).  0 = CNROM.  1 = MMC1.  
 
     .res $38
 

src/reset.asm

@@ -53,7 +53,7 @@ reset:  cld
 
 mapperInit:
 ; autodetect
-.if INES_MAPPER = 0
+.if INES_MAPPER = 255
         setMMC1PRG ; initialize mmc1 just in case
         ; cnrom can pass one of these tests but not both.
         ; Start with the one it's supposed to fail.

src/util/mapper.asm

@@ -30,7 +30,6 @@
 .endmacro
 
 _setMMC1Control:
-.if INES_MAPPER = 0 .or INES_MAPPER = 1
         RESET_MMC1
         sta MMC1_Control
         lsr a
@@ -41,15 +40,14 @@ _setMMC1Control:
         sta MMC1_Control
         lsr a
         sta MMC1_Control
-.endif
         rts
 
 changeCHRBanks:
         ; accum should be 0 or 2 (CHRBankset0 or CHRBankset1)
         sta     generalCounter
 
 ; autodetect
-.if INES_MAPPER = 0
+.if INES_MAPPER = 255
         ldx     mapperId
         beq     @cnrom
         changeCHRBanksMMC1
@@ -112,7 +110,7 @@ changeCHRBanks:
 
 setHorizontalMirroring:
 ; autodetect
-.if INES_MAPPER = 0
+.if INES_MAPPER = 255
         lda mapperId
         beq @cnrom
         lda #%10011
@@ -140,10 +138,10 @@ setHorizontalMirroring:
         rts
 
 setVerticalMirroring:
-; Unused except during mapper detect for INES_MAPPER 0 
+; Unused except during mapper detect for INES_MAPPER 255
 
 ; autodetect
-.if INES_MAPPER = 0
+.if INES_MAPPER = 255
         lda mapperId
         beq @cnrom
         lda #%10010
@@ -170,7 +168,7 @@ setVerticalMirroring:
 .endif
         rts
 
-.if INES_MAPPER = 0 .or INES_MAPPER = 3
+.if INES_MAPPER = 3 .or INES_MAPPER = 255
 ; bus conflict workaround
 cnromBanks:
         .byte $00,$01