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player/Project/Src/NES/mapper/009.cpp

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2025-06-27 00:32:57 +08:00
#include "nes_mapper.h"
void MAP9_set_VROM_1000(void);
void MAP9_set_VROM_0000(void);
uint8 MAP9_regs[6];
uint8 MAP9_latch_0000;
uint8 MAP9_latch_1000;
/////////////////////////////////////////////////////////////////////
// Mapper 9
void MAP9_Reset()
{
int i;
// // set CPU bank pointers
// set_CPU_banks(0,num_8k_ROM_banks-3,num_8k_ROM_banks-2,num_8k_ROM_banks-1);
for( i = 0; i < sizeof(MAP9_regs)/sizeof(MAP9_regs[0]); i++)
MAP9_regs[i] = 0;
MAP9_regs[2] = 4;
MAP9_latch_0000 = 0xFE;
MAP9_latch_1000 = 0xFE;
MAP9_set_VROM_0000();
MAP9_set_VROM_1000();
}
void MAP9_PPU_Latch_FDFE(uint32 addr)
{
if(addr & 0x1000)
{
MAP9_latch_1000 = (addr & 0x0FF0) >> 4;
MAP9_set_VROM_1000();
}
else
{
MAP9_latch_0000 = (addr & 0x0FF0) >> 4;
MAP9_set_VROM_0000();
}
}
void MAP9_set_VROM_0000()
{
int bank_num = (MAP9_latch_0000 == 0xFD) ? MAP9_regs[1] : MAP9_regs[2];
bank_num <<= 2;
set_PPU_bank0(bank_num+0);
set_PPU_bank1(bank_num+1);
set_PPU_bank2(bank_num+2);
set_PPU_bank3(bank_num+3);
}
void MAP9_set_VROM_1000()
{
int bank_num = (MAP9_latch_1000 == 0xFD) ? MAP9_regs[3] : MAP9_regs[4];
bank_num <<= 2;
set_PPU_bank4(bank_num+0);
set_PPU_bank5(bank_num+1);
set_PPU_bank6(bank_num+2);
set_PPU_bank7(bank_num+3);
}
void MAP9_MemoryWrite(uint16 addr, uint8 data)
{
uint8 bank_num ;
switch(addr & 0xF000)
{
case 0xA000:
{
MAP9_regs[0] = data;
// 8K ROM bank at $8000
bank_num = MAP9_regs[0];
set_CPU_bank4(bank_num);
}
break;
case 0xB000:
{
// B000-BFFF: select 4k VROM for (0000) $FD latch
MAP9_regs[1] = data;
MAP9_set_VROM_0000();
}
break;
case 0xC000:
{
// C000-CFFF: select 4k VROM for (0000) $FE latch
MAP9_regs[2] = data;
MAP9_set_VROM_0000();
}
break;
case 0xD000:
{
// D000-DFFF: select 4k VROM for (1000) $FD latch
MAP9_regs[3] = data;
MAP9_set_VROM_1000();
}
break;
case 0xE000:
{
// E000-EFFF: select 4k VROM for (1000) $FE latch
MAP9_regs[4] = data;
MAP9_set_VROM_1000();
}
break;
case 0xF000:
{
MAP9_regs[5] = data;
if(MAP9_regs[5] & 0x01)
{
set_mirroring(0,0,1,1);//ˮƽ<CBAE><C6BD><EFBFBD><EFBFBD>InfoNES_Mirroring( 0 ); //0011
//set_mirroring(NES_PPU::MIRROR_HORIZ);
}
else
{
set_mirroring(0,1,0,1);//<2F><>ֱ<EFBFBD><D6B1><EFBFBD><EFBFBD>InfoNES_Mirroring( 1 ); //0101
//set_mirroring(NES_PPU::MIRROR_VERT);
}
}
break;
}
}
void MAP9_SNSS_fixup()
{
MAP9_set_VROM_0000();
MAP9_set_VROM_1000();
}
void MAP9_Init()
{
NES_Mapper->Reset = MAP9_Reset;
NES_Mapper->Write = MAP9_MemoryWrite;
}