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mapper0.go
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mapper0.go
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package main
import "fmt"
type MapperMMC0 struct {
nes *Nes
}
func NewMapperMMC0(nes *Nes) *MapperMMC0 {
return &MapperMMC0{
nes: nes,
}
}
func (m *MapperMMC0) Read(addr address) byte {
switch {
case addr <= 0x1FFF:
return m.nes.cartridge.chr[addr]
case addr <= 0x2FFF:
return m.nes.ppu.vram[TranslateVRamAddress(addr, m.nes.cartridge.mirrorMode)]
case addr >= 0x8000 && addr <= 0xBFFF:
return m.nes.cartridge.prg[addr-0x8000]
case addr >= 0xC000 && addr <= 0xFFFF:
if len(m.nes.cartridge.prg) > 0x4000 {
return m.nes.cartridge.prg[addr-0x8000]
} else {
return m.nes.cartridge.prg[addr-0xC000]
}
default:
//panic(fmt.Sprintf("MMC read out of bounds: %.4X", addr))
}
return 0
}
func (m *MapperMMC0) Write(addr address, data byte) {
switch {
case addr <= 0x1FFF:
fmt.Printf("$%.4X : %.2X | AT $%.4X ---------------------------\n", addr, data, nes.cpu.PC)
m.nes.cartridge.chr[addr] = data // if RAM
case addr <= 0x2FFF:
m.nes.ppu.vram[TranslateVRamAddress(addr, m.nes.cartridge.mirrorMode)] = data
default:
// panic(fmt.Sprintf("MMC write out of bounds: %.4X", addr))
}
}