Files
player/Project/Src/NES/mapper/073.cpp
2025-06-27 00:32:57 +08:00

106 lines
1.4 KiB
C++

#include "nes_mapper.h"
u8 map73_irq_enabled=0;
u8 map73_irq_counter=0;
// Mapper 73
void MAP73_Reset()
{
// set CPU bank pointers
// set_CPU_banks(0,1,num_8k_ROM_banks-2,num_8k_ROM_banks-1);
map73_irq_enabled = 0;
map73_irq_enabled = 0;
}
void MAP73_MemoryWrite(uint16 addr, uint8 data)
{
switch(addr)
{
case 0x8000:
{
map73_irq_enabled = (map73_irq_enabled & 0xFFF0) | (data & 0x0F);
}
break;
case 0x9000:
{
map73_irq_enabled = (map73_irq_enabled & 0xFF0F) | ((data & 0x0F) << 4);
}
break;
case 0xA000:
{
map73_irq_enabled = (map73_irq_enabled & 0xF0FF) | ((data & 0x0F) << 8);
}
break;
case 0xB000:
{
map73_irq_enabled = (map73_irq_enabled & 0x0FFF) | ((data & 0x0F) << 12);
}
break;
case 0xC000:
{
map73_irq_enabled = data;
}
break;
case 0xF000:
{
set_CPU_bank4(data*2+0);
set_CPU_bank5(data*2+1);
}
break;
}
}
void MAP73_HSync(int scanline)
{
if(map73_irq_enabled & 0x02)
{
if(map73_irq_enabled > 0xFFFF - 114)
{
CPU_IRQ;
map73_irq_enabled = 0;
}
else
{
map73_irq_enabled += 114;
}
}
}
void MAP73_Init()
{
NES_Mapper->Reset = MAP73_Reset;
NES_Mapper->Write = MAP73_MemoryWrite;
NES_Mapper->HSync = MAP73_HSync;
}