diff --git a/.gitignore b/.gitignore
index 6378da1..d00c189 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@ cpu.prof
 mem.prof
 mos6502go.test
 apple2e.rom
+dos33_disk.dsk
diff --git a/audio/audio.go b/audio/audio.go
index 4cedd03..fa1c480 100644
--- a/audio/audio.go
+++ b/audio/audio.go
@@ -1,84 +1,9 @@
 package audio
 
 import (
-	"errors"
 	"mos6502go/system"
-
-	ebiten_audio "github.com/hajimehoshi/ebiten/audio"
 )
 
-var (
-	audioContext *ebiten_audio.Context
-	player       *ebiten_audio.Player
-	firstAudio   bool
-	Mute         bool
-)
-
-type stream struct{}
-
-func (s *stream) Read(data []byte) (int, error) {
-	dataLen := len(data)
-
-	if firstAudio {
-		// The first time, drain the audio queue
-		firstAudio = false
-
-		for i := 0; i < len(system.AudioChannel); i++ {
-			<-system.AudioChannel
-		}
-		return dataLen, nil
-	}
-
-	if dataLen%4 != 0 {
-		return 0, errors.New("dataLen % 4 must be 0")
-	}
-
-	if Mute {
-		return dataLen, nil
-	}
-
-	samples := dataLen / 4
-
-	for i := 0; i < dataLen; i++ {
-		data[i] = 0
-	}
-
-	for i := 0; i < samples; i++ {
-		b := <-system.AudioChannel
-
-		data[4*i] = byte(b)
-		data[4*i+1] = byte(b >> 8)
-		data[4*i+2] = byte(b)
-		data[4*i+3] = byte(b >> 8)
-	}
-
-	return dataLen, nil
-}
-
-func (s *stream) Close() error {
-	return nil
-}
-
-func Init() {
-	firstAudio = true
-	Mute = false
-
-	var err error
-	audioContext, err = ebiten_audio.NewContext(system.AudioSampleRate)
-	if err != nil {
-		panic(err)
-	}
-
-	// Pass the (infinite) stream to audio.NewPlayer.
-	// After calling Play, the stream never ends as long as the player object lives.
-	// var err error
-	player, err = ebiten_audio.NewPlayer(audioContext, &stream{})
-	if err != nil {
-		panic(err)
-	}
-	player.Play()
-}
-
 func Click() {
 	ForwardToFrameCycle()
 	system.AudioAttenuationCounter = 400
diff --git a/audio/ebiten.go b/audio/ebiten.go
new file mode 100644
index 0000000..9d4ea22
--- /dev/null
+++ b/audio/ebiten.go
@@ -0,0 +1,80 @@
+package audio
+
+import (
+	"errors"
+	"mos6502go/system"
+
+	ebiten_audio "github.com/hajimehoshi/ebiten/audio"
+)
+
+var (
+	audioContext *ebiten_audio.Context
+	player       *ebiten_audio.Player
+	firstAudio   bool
+	Mute         bool
+)
+
+type stream struct{}
+
+func (s *stream) Read(data []byte) (int, error) {
+	dataLen := len(data)
+
+	if firstAudio {
+		// The first time, drain the audio queue
+		firstAudio = false
+
+		for i := 0; i < len(system.AudioChannel); i++ {
+			<-system.AudioChannel
+		}
+		return dataLen, nil
+	}
+
+	if dataLen%4 != 0 {
+		return 0, errors.New("dataLen % 4 must be 0")
+	}
+
+	if Mute {
+		return dataLen, nil
+	}
+
+	samples := dataLen / 4
+
+	for i := 0; i < dataLen; i++ {
+		data[i] = 0
+	}
+
+	for i := 0; i < samples; i++ {
+		b := <-system.AudioChannel
+
+		data[4*i] = byte(b)
+		data[4*i+1] = byte(b >> 8)
+		data[4*i+2] = byte(b)
+		data[4*i+3] = byte(b >> 8)
+	}
+
+	return dataLen, nil
+}
+
+func (s *stream) Close() error {
+	return nil
+}
+
+func InitEbiten() {
+	firstAudio = true
+	Mute = false
+
+	var err error
+	audioContext, err = ebiten_audio.NewContext(system.AudioSampleRate)
+	if err != nil {
+		panic(err)
+	}
+
+	// Pass the (infinite) stream to audio.NewPlayer.
+	// After calling Play, the stream never ends as long as the player object lives.
+	// var err error
+	player, err = ebiten_audio.NewPlayer(audioContext, &stream{})
+	if err != nil {
+		panic(err)
+	}
+	player.Play()
+}
diff --git a/cmd/test-apple-iie-boot.go b/cmd/test-apple-iie-boot.go
index 49e9718..2ce847b 100644
--- a/cmd/test-apple-iie-boot.go
+++ b/cmd/test-apple-iie-boot.go
@@ -86,7 +86,7 @@ func main() {
 
 	keyboard.Init()
 	video.Init()
-	audio.Init()
+	audio.InitEbiten()
 	audio.Mute = *mute
 	system.Init()
 
diff --git a/dos33_boot_test.go b/dos33_boot_test.go
new file mode 100644
index 0000000..7b95844
--- /dev/null
+++ b/dos33_boot_test.go
@@ -0,0 +1,43 @@
+package main_test
+
+import (
+	"fmt"
+	"mos6502go/cpu"
+	"mos6502go/keyboard"
+	"mos6502go/mmu"
+	"mos6502go/system"
+	"mos6502go/video"
+	"testing"
+	"time"
+)
+
+const DiskImage = "dos33_disk.dsk"
+
+func TestDOS33Boot(t *testing.T) {
+	cpu.InitInstructionDecoder()
+	mmu.InitRAM()
+	mmu.InitApple2eROM()
+	mmu.InitIO()
+	mmu.ReadDiskImage(DiskImage)
+	cpu.Init()
+	keyboard.Init()
+	video.Init()
+	system.Init()
+	cpu.Reset()
+
+	system.FrameCycles = 0
+	system.LastAudioCycles = 0
+	showInstructions := false
+	var breakAddress uint16
+	disableFirmwareWait := false
+	t0 := time.Now()
+	cpu.Run(showInstructions, &breakAddress, disableFirmwareWait, system.CpuFrequency*1000)
+
+	// audio.ForwardToFrameCycle()
+
+	elapsed := float64(time.Since(t0) / time.Millisecond)
+	fmt.Printf("CPU Cycles:    %d\n", system.FrameCycles)
+	// fmt.Printf("Sound samples: %d\n", len(system.AudioChannel))
+	fmt.Printf("Time elapsed:  %0.2f ms\n", elapsed)
+	fmt.Printf("Speed:         %0.2f cycles/ms\n", float64(system.FrameCycles)/elapsed)
+}