func NewRP2A03(apuFrequency int) *RP2A03 {
mem := NewMappedMemory(m65go2.NewBasicMemory(m65go2.DefaultMemorySize))
mirrors := make(map[uint32]uint32)
// Mirrored 2KB internal RAM
for i := uint32(0x0800); i <= 0x1fff; i++ {
mirrors[i] = i % 0x0800
}
// Mirrored PPU registers
for i := uint32(0x2008); i <= 0x3fff; i++ {
mirrors[i] = 0x2000 + (i & 0x0007)
}
mem.AddMirrors(mirrors)
cpu := m65go2.NewM6502(mem)
cpu.DisableDecimalMode()
apu := NewAPU(mem, uint64(1789773/apuFrequency), cpu.InterruptLine(m65go2.Irq))
// APU memory maps
mem.AddMappings(apu, CPU)
dma := NewDMA(mem)
// DMA memory maps
mem.AddMappings(dma, CPU)
return &RP2A03{
Memory: mem,
M6502: cpu,
APU: apu,
DMA: dma,
}
}
func NewOAM() *OAM {
cycleFuncs := []CycleFunc{
ClearBuffer: clearBuffer,
CopyYPosition: copyYPosition,
CopyIndex: copyIndex,
CopyAttributes: copyAttributes,
CopyXPosition: copyXPosition,
EvaluateYPosition: evaluateYPosition,
EvaluateIndex: evaluateIndex,
EvaluateAttributes: evaluateAttributes,
EvaluateXPosition: evaluateXPosition,
FailCopyYPosition: failCopyYPosition,
}
return &OAM{
BasicMemory: m65go2.NewBasicMemory(256),
Buffer: m65go2.NewBasicMemory(32),
SpriteZeroInBuffer: false,
cycleFuncs: cycleFuncs,
WriteCycle: FailCopyYPosition,
}
}
func NewRP2C02(interrupt func(bool), region string) *RP2C02 {
mem := rp2ago3.NewMappedMemory(m65go2.NewBasicMemory(m65go2.DefaultMemorySize))
mirrors := make(map[uint32]uint32)
// Mirrored nametables
for i := uint32(0x3000); i <= 0x3eff; i++ {
mirrors[i] = i - 0x1000
}
// Mirrored palette
for _, i := range []uint32{0x3f10, 0x3f14, 0x3f18, 0x3f1c} {
mirrors[i] = i - 0x0010
}
for i := uint32(0x3f20); i <= 0x3fff; i++ {
mirrors[i] = 0x3f00 + (i & 0x001f)
}
nametable := NewNametable()
mem.AddMappings(nametable, rp2ago3.PPU)
mem.AddMirrors(mirrors)
ppu := &RP2C02{
colors: make([]uint8, 0xf000),
Memory: mem,
Nametable: nametable,
Interrupt: interrupt,
OAM: NewOAM(),
ShowBackground: true,
ShowSprites: true,
PAL: region == "PAL",
}
if !ppu.PAL {
ppu.NumScanlines = NumScanlinesNTSC
ppu.PreRenderScanline = PreRenderScanlineNTSC
} else {
ppu.NumScanlines = NumScanlinesPAL
ppu.PreRenderScanline = PreRenderScanlinePAL
}
ppu.initCycleJumpTable()
mem.AddMappings(ppu, rp2ago3.PPU)
return ppu
}