wip

pkg/gba/apu.go

@@ -4,7 +4,6 @@ import (
 	"math"
 	"mettaur/pkg/ram"
 	"mettaur/pkg/util"
-	"time"
 
 	"github.com/hajimehoshi/oto"
 )
@@ -18,6 +17,14 @@ func isWaveRAM(addr uint32) bool {
 	return addr >= 0x04000090 && addr <= 0x0400009f
 }
 
+func isResetSoundChan(addr uint32) bool {
+	return addr == 0x04000065 || addr == 0x0400006d || addr == 0x04000075 || addr == 0x0400007d
+}
+func (g *GBA) resetSoundChan(addr uint32, b byte) {
+	m := map[uint32]int{0x04000065: 0, 0x0400006d: 1, 0x04000075: 2, 0x0400007d: 3}
+	g._resetSoundChan(m[addr], b&0x80 != 0)
+}
+
 const (
 	CPU_FREQ_HZ              = 16777216
 	SND_FREQUENCY            = 32768
@@ -57,9 +64,9 @@ type SoundChan struct {
 }
 
 func newAPU() *APU {
-	stream = make([]byte, BUFF_SAMPLES*2)
+	stream = make([]byte, BUFF_SAMPLES)
 
-	context, err := oto.NewContext(SND_FREQUENCY, 2, 2, 512)
+	context, err := oto.NewContext(SND_FREQUENCY, 2, 2, BUFF_SAMPLES)
 	if err != nil {
 		panic(err)
 	}
@@ -78,19 +85,15 @@ func (g *GBA) exitAPU() {
 
 func (g *GBA) playSound() {
 	go func() {
-		for range time.Tick(time.Second / 60) {
-			g.updateSound()
-			g.writeSound()
+		for {
+			g.soundMix()
+		}
+	}()
+	go func() {
+		for {
+			g.apu.player.Write(stream)
 		}
 	}()
-}
-
-func (g *GBA) writeSound() {
-	g.apu.player.Write(stream)
-}
-
-func (g *GBA) updateSound() {
-	g.soundMix()
 }
 
 func (g *GBA) squareSample(ch int) int8 {
@@ -388,7 +391,7 @@ var sndBuffer [BUFF_SAMPLES]int16
 var stream []byte
 
 func (g *GBA) soundMix() {
-	for i := 0; i < len(sndBuffer); i += 4 {
+	for i := 0; i < BUFF_SAMPLES; i += 4 {
 		snd := sndBuffer[sndCurPlay&BUFF_SAMPLES_MSK] << 6
 		stream[i+0], stream[i+1] = byte(snd), byte(snd>>8)
 		sndCurPlay++
@@ -532,7 +535,7 @@ func (g *GBA) soundClock(cycles uint32) {
 	}
 }
 
-func (g *GBA) resetSoundChan(ch int, enable bool) {
+func (g *GBA) _resetSoundChan(ch int, enable bool) {
 	if enable {
 		g.apu.chans[ch] = &SoundChan{
 			phase:      false,

pkg/gba/io.go

@@ -100,6 +100,9 @@ func (g *GBA) _setRAM8(addr uint32, b byte) {
 	switch {
 	case gpu.IsIO(addr):
 		g.GPU.IO[addr-0x0400_0000] = b
+	case isResetSoundChan(addr):
+		g.RAM.Set8(addr, b)
+		g.resetSoundChan(addr, b)
 	case isWaveRAM(addr):
 		bank := (g._getRAM(ram.SOUND3CNT_L) >> 2) & 0x10
 		idx := (bank ^ 0x10) | (addr & 0xf)