mappers/27.c

   1 #include "mapinc.h"
   2
   3 static uint32 regchr[9];
   4
   5 static DECLFW(Mapper27_write)
   6 {
   7  A&=0xF00F;
   8  int regnum;
   9  if((A>=0xB000) && (A<=0xE003)) {
  10     regnum=((((A>>12)+1)&0x03)<<1)|((A&0x02)>>1);
  11     if(A&1)
  12        regchr[regnum]=(regchr[regnum]&0x0F)|(V<<4);
  13     else
  14        regchr[regnum]=(regchr[regnum]&0xFF0)|(V&0xF);
  15     VROM_BANK1(regnum<<10,regchr[regnum]);
  16  }
  17  switch(A)
  18  {
  19   case 0x8000: if(regchr[8]&2)
  20                   ROM_BANK8(0xc000,V);
  21                else
  22                   ROM_BANK8(0x8000,V);
  23                break;
  24   case 0xA000: ROM_BANK8(0xa000,V); break;
  25   case 0x9000:
  26                switch(V&3){
  27                   case 0:setmirror(MI_V);break;
  28                   case 1:setmirror(MI_H);break;
  29                   case 2:setmirror(MI_0);break;
  30                   case 3:setmirror(MI_1);break;
  31                }
  32   case 0x9002: regchr[8]=V; break;
  33   case 0xF000: //X6502_IRQEnd(FCEU_IQEXT);
  34                IRQLatch=(IRQLatch&0xF0)|(V&0x0F);
  35                            break;
  36   case 0xF001: //X6502_IRQEnd(FCEU_IQEXT);
  37                IRQLatch=(IRQLatch&0x0F)|((V&0xF)<<4);
  38                            break;
  39   case 0xF003: IRQa=((IRQa&0x1)<<1)|(IRQa&0x1);
  40                            X6502_IRQEnd(FCEU_IQEXT);
  41                break;
  42   case 0xF002: IRQa=V&3;
  43                            if(IRQa&0x02) IRQCount=IRQLatch;
  44                            X6502_IRQEnd(FCEU_IQEXT);
  45                            break;
  46  }
  47 // if((A&0xF000)==0xF000) FCEU_printf("$%04x:$%02x, %d\n",A,V, scanline);
  48 }
  49
  50 static void Mapper27_hb(void)
  51 {
  52 //   FCEU_printf("%02x-%d,%d,%d\n",scanline,IRQa,IRQCount,IRQLatch);
  53         if(IRQa&0x2){
  54            if(IRQCount==0xFF){
  55              X6502_IRQBegin(FCEU_IQEXT);
  56               IRQCount=IRQLatch+1;
  57          } else {
  58            IRQCount++;
  59            }
  60         }
  61 }
  62
  63 void Mapper27_init(void)
  64 {
  65   int i;
  66   for (i=0; i<9; i++) {
  67     regchr[i]=0;
  68   }
  69   IRQa=0;
  70   IRQCount=IRQLatch=0;
  71   SetWriteHandler(0x8000,0xffff,Mapper27_write);
  72   GameHBIRQHook=Mapper27_hb;
  73 }
  74