Moved disk module out of mmu

appleiie.go

@@ -9,6 +9,7 @@ import (
 
 	"mos6502go/audio"
 	"mos6502go/cpu"
+	"mos6502go/disk"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
@@ -95,7 +96,7 @@ func main() {
 	mmu.InitIO()
 
 	if diskImage != "" {
-		mmu.ReadDiskImage(diskImage)
+		disk.ReadDiskImage(diskImage)
 	}
 
 	cpu.Init()
@@ -110,5 +111,5 @@ func main() {
 
 	ebiten.Run(update, 280*video.ScreenSizeFactor, 192*video.ScreenSizeFactor, 2, "Apple //e")
 
-	mmu.FlushImage()
+	disk.FlushImage()
 }

bank_switch_test.go

@@ -1,14 +1,15 @@
 package main
 
 import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
 	"mos6502go/cpu"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/video"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
 )
 
 func TestBankSwitching(t *testing.T) {

bell_test.go

@@ -2,12 +2,13 @@ package main
 
 import (
 	"fmt"
+	"testing"
+
 	"mos6502go/cpu"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/video"
-	"testing"
 )
 
 func testBellCycles(delay int) {

disk/disk.go

@@ -1,8 +1,10 @@
-package mmu
+package disk
 
 import (
 	"fmt"
 	"io/ioutil"
+
+	"mos6502go/system"
 )
 
 const tracksPerDisk = 35
@@ -301,7 +303,7 @@ func MakeTrackData(armPosition uint8) {
 		return
 	}
 
-	DriveState.BytePosition = 0 // Point the head at the first sector
+	system.DriveState.BytePosition = 0 // Point the head at the first sector
 
 	// For each sector, encode the data and add it to trackData
 	for physicalSector := uint8(0); physicalSector < sectorsPerTrack; physicalSector++ {
@@ -319,22 +321,22 @@ func decodeAddressField(data []uint8) addressField {
 
 // Read a byte from the disk head and spin the disk along
 func ReadTrackData() (result uint8) {
-	result = trackData[DriveState.BytePosition]
+	result = trackData[system.DriveState.BytePosition]
 
-	if DriveState.BytePosition >= 9 {
-		if trackData[DriveState.BytePosition-9] == 0xd5 &&
-			trackData[DriveState.BytePosition-8] == 0xaa &&
-			trackData[DriveState.BytePosition-7] == 0x96 {
+	if system.DriveState.BytePosition >= 9 {
+		if trackData[system.DriveState.BytePosition-9] == 0xd5 &&
+			trackData[system.DriveState.BytePosition-8] == 0xaa &&
+			trackData[system.DriveState.BytePosition-7] == 0x96 {
 			var addressData []uint8
-			addressData = trackData[DriveState.BytePosition-6 : DriveState.BytePosition]
+			addressData = trackData[system.DriveState.BytePosition-6 : system.DriveState.BytePosition]
 			lastReadAddress = decodeAddressField(addressData)
-			lastReadSectorDataPosition = DriveState.BytePosition + 8
+			lastReadSectorDataPosition = system.DriveState.BytePosition + 8
 		}
 	}
 
-	DriveState.BytePosition++
-	if DriveState.BytePosition == trackDataBytes {
-		DriveState.BytePosition = 0
+	system.DriveState.BytePosition++
+	if system.DriveState.BytePosition == trackDataBytes {
+		system.DriveState.BytePosition = 0
 	}
 
 	return

dos33_boot_test.go

@@ -2,14 +2,16 @@ package main
 
 import (
 	"fmt"
+	"testing"
+	"time"
+
 	"mos6502go/cpu"
+	"mos6502go/disk"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/utils"
 	"mos6502go/video"
-	"testing"
-	"time"
 )
 
 const dosDiskImage = "dos33.dsk"
@@ -27,7 +29,7 @@ func TestDOS33Boot(t *testing.T) {
 	mmu.InitRAM()
 	mmu.InitApple2eROM()
 	mmu.InitIO()
-	mmu.ReadDiskImage(dosDiskImage)
+	disk.ReadDiskImage(dosDiskImage)
 	cpu.Init()
 	keyboard.Init()
 	video.Init()

io_test.go

@@ -1,14 +1,15 @@
 package main
 
 import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
 	"mos6502go/cpu"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/video"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
 )
 
 func TestIoBankSwitching(t *testing.T) {

mmu/io.go

@@ -2,8 +2,11 @@ package mmu
 
 import (
 	"fmt"
+
 	"mos6502go/audio"
+	"mos6502go/disk"
 	"mos6502go/keyboard"
+	"mos6502go/system"
 )
 
 // Adapted from
@@ -90,16 +93,6 @@ const (
 	S6Q7H      = 0xC0EF // write
 )
 
-var DriveState struct {
-	Drive        uint8
-	Spinning     bool
-	Phase        int8
-	Phases       uint8
-	BytePosition int
-	Q6           bool
-	Q7           bool
-}
-
 var VideoState struct {
 	TextMode  bool
 	HiresMode bool
@@ -113,22 +106,22 @@ func InitIO() {
 	emptySlot(7)
 
 	// Initialize slot 6 drive
-	DriveState.Drive = 1
-	DriveState.Spinning = false
-	DriveState.Phase = 0
-	DriveState.BytePosition = 0
-	DriveState.Q6 = false
-	DriveState.Q7 = false
+	system.DriveState.Drive = 1
+	system.DriveState.Spinning = false
+	system.DriveState.Phase = 0
+	system.DriveState.BytePosition = 0
+	system.DriveState.Q6 = false
+	system.DriveState.Q7 = false
 
 	VideoState.TextMode = true
 	VideoState.HiresMode = false
 	VideoState.Mixed = false
 
-	InitDiskImage()
+	disk.InitDiskImage()
 }
 
 func driveIsreadSequencing() bool {
-	return (!DriveState.Q6) && (!DriveState.Q7)
+	return (!system.DriveState.Q6) && (!system.DriveState.Q7)
 }
 
 // Handle soft switch addresses where both a read and a write has a side
@@ -209,68 +202,68 @@ func readWrite(address uint16, isRead bool) bool {
 		on := ((address - S6CLRDRVP0) % 2) == 1
 
 		if on {
-			DriveState.Phases |= (1 << magnet)
+			system.DriveState.Phases |= (1 << magnet)
 
 			// Move head if a neighboring magnet is on and all others are off
 			direction := int8(0)
-			if (DriveState.Phases & (1 << uint8((DriveState.Phase+1)&3))) != 0 {
+			if (system.DriveState.Phases & (1 << uint8((system.DriveState.Phase+1)&3))) != 0 {
 				direction += 1
 			}
-			if (DriveState.Phases & (1 << uint8((DriveState.Phase+3)&3))) != 0 {
+			if (system.DriveState.Phases & (1 << uint8((system.DriveState.Phase+3)&3))) != 0 {
 				direction -= 1
 			}
 
 			if direction != 0 {
-				DriveState.Phase += direction
+				system.DriveState.Phase += direction
 
-				if DriveState.Phase < 0 {
-					DriveState.Phase = 0
+				if system.DriveState.Phase < 0 {
+					system.DriveState.Phase = 0
 				}
-				if DriveState.Phase == 80 {
-					DriveState.Phase = 79
+				if system.DriveState.Phase == 80 {
+					system.DriveState.Phase = 79
 				}
 
-				MakeTrackData(uint8(DriveState.Phase))
+				disk.MakeTrackData(uint8(system.DriveState.Phase))
 
 				if audio.ClickWhenDriveHeadMoves {
 					audio.Click()
 				}
 			}
 		} else {
-			DriveState.Phases &= ^(1 << magnet)
+			system.DriveState.Phases &= ^(1 << magnet)
 		}
 
 		return true
 
 	case S6MOTOROFF:
-		DriveState.Spinning = false
+		system.DriveState.Spinning = false
 		return true
 	case S6MOTORON:
-		DriveState.Spinning = true
+		system.DriveState.Spinning = true
 		return true
 	case S6SELDRV1:
-		DriveState.Drive = 1
+		system.DriveState.Drive = 1
 		return true
 	case S6SELDRV2:
-		DriveState.Drive = 2
+		system.DriveState.Drive = 2
 		return true
 	case S6Q6L:
 		if !isRead {
-			DriveState.Q6 = false
+			system.DriveState.Q6 = false
 			return true
 		}
 		return false
 	case S6Q6H:
 		if isRead {
-			DriveState.Q6 = true
+			system.DriveState.Q6 = true
 			return true
 		}
 		return false
 	case S6Q7L:
-		DriveState.Q7 = false
+		system.DriveState.Q7 = false
 		return true
 	case S6Q7H:
-		DriveState.Q7 = true
+		system.DriveState.Q7 = true
 		return true
 
 	default:
@@ -332,7 +325,7 @@ func ReadIO(address uint16) uint8 {
 	case SPEAKER:
 		audio.Click()
 	case S6Q6L:
-		return ReadTrackData()
+		return disk.ReadTrackData()
 	default:
 		panic(fmt.Sprintf("TODO read %04x\n", address))
 	}
@@ -364,7 +357,7 @@ func WriteIO(address uint16, value uint8) {
 	case SETC3ROM:
 		// SETC3ROM not implemented
 	case S6Q6H:
-		WriteTrackData(value)
+		disk.WriteTrackData(value)
 	default:
 		panic(fmt.Sprintf("TODO write %04x\n", address))
 	}

prodos_boot_test.go

@@ -2,14 +2,16 @@ package main
 
 import (
 	"fmt"
+	"testing"
+	"time"
+
 	"mos6502go/cpu"
+	"mos6502go/disk"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/utils"
 	"mos6502go/video"
-	"testing"
-	"time"
 )
 
 const prodosDiskImage = "prodos.dsk"
@@ -19,7 +21,7 @@ func TestProdosBoot(t *testing.T) {
 	mmu.InitRAM()
 	mmu.InitApple2eROM()
 	mmu.InitIO()
-	mmu.ReadDiskImage(prodosDiskImage)
+	disk.ReadDiskImage(prodosDiskImage)
 	cpu.Init()
 	keyboard.Init()
 	video.Init()

rwts_write_test.go

@@ -1,14 +1,15 @@
 package main
 
 import (
+	"testing"
+
 	"mos6502go/cpu"
+	"mos6502go/disk"
 	"mos6502go/keyboard"
 	"mos6502go/mmu"
 	"mos6502go/system"
 	"mos6502go/utils"
 	"mos6502go/video"
-
-	"testing"
 )
 
 const rwtsDosDiskImage = "dos33.dsk"
@@ -25,7 +26,7 @@ func TestDos33RwtsWriteRead(t *testing.T) {
 	mmu.InitRAM()
 	mmu.InitApple2eROM()
 	mmu.InitIO()
-	mmu.ReadDiskImage(rwtsDosDiskImage)
+	disk.ReadDiskImage(rwtsDosDiskImage)
 	cpu.Init()
 	keyboard.Init()
 	video.Init()

system/system.go

@@ -19,6 +19,16 @@ var (
 	AudioAttenuationCounter uint64
 )
 
+var DriveState struct {
+	Drive        uint8
+	Spinning     bool
+	Phase        int8
+	Phases       uint8
+	BytePosition int
+	Q6           bool
+	Q7           bool
+}
+
 func Init() {
 	Cycles = 0
 	AudioChannel = make(chan int16, AudioSampleRate*4) // 1 second