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package nes
import (
"crecher.net/gones/v2/cart"
"crecher.net/gones/v2/cpu"
"crecher.net/gones/v2/ppu"
)
type Console struct {
CPU *cpu.CPU
PPU *ppu.PPU
Cart *cart.Cartridge
RAM [0x800]uint8
controllers [2]controller
dmaPending bool
// APU once it exists
cycles uint64
}
func New(c *cart.Cartridge) *Console {
n := &Console{Cart: c}
n.PPU = ppu.New(c.Mapper, c.Mirroring)
n.CPU = cpu.NewCPU(n)
n.CPU.Reset()
return n
}
func (n *Console) Step() int {
cycles := n.CPU.Step()
if n.dmaPending {
n.dmaPending = false
stall := n.dmaStallCycles()
n.CPU.Stall(stall)
cycles += stall
}
n.cycles += uint64(cycles)
for i := 0; i < cycles*3; i++ {
n.PPU.Tick()
if n.PPU.PollNMI() {
n.CPU.NMI()
}
}
return cycles
}
// runs until the PPU finishes a frame, the framebuffer then holds a full picture
func (n *Console) StepFrame() {
frame := n.PPU.Frame
for n.PPU.Frame == frame {
n.Step()
}
}
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