Rework of the memory manager. No longer based on pages, but on bigger go byte ranges

apple2/ansiConsoleFrontend.go

@@ -21,27 +21,17 @@ type ansiConsoleFrontend struct {
 	apple2         *Apple2
 	keyChannel     chan uint8
 	extraLineFeeds chan int
-	textUpdated    bool
 	stdinKeyboard  bool
+	lastContent    string
 }
 
 func newAnsiConsoleFrontend(a *Apple2, stdinKeyboard bool) *ansiConsoleFrontend {
 	var fe ansiConsoleFrontend
 	fe.apple2 = a
 	fe.stdinKeyboard = stdinKeyboard
-	fe.subscribeToTextPages()
 	return &fe
 }
 
-func (fe *ansiConsoleFrontend) subscribeToTextPages() {
-	observer := func(_ uint8, _ bool) {
-		fe.textUpdated = true
-	}
-	for i := 0x04; i < 0x08; i++ {
-		fe.apple2.mmu.physicalMainRAM[i].observer = observer
-	}
-}
-
 const refreshDelayMs = 100
 
 func (fe *ansiConsoleFrontend) GetKey(strobed bool) (key uint8, ok bool) {
@@ -85,101 +75,53 @@ func (fe *ansiConsoleFrontend) GetKey(strobed bool) (key uint8, ok bool) {
 	return
 }
 
-func ansiCursorUp(steps int) {
-	fmt.Printf("\033[%vA", steps)
-}
-
-func (fe *ansiConsoleFrontend) textModeGoRoutineFast() {
-	fe.extraLineFeeds = make(chan int, 100)
-
-	fmt.Printf(strings.Repeat("\n", 26))
-	for {
-		if fe.textUpdated {
-			fe.textUpdated = false
-			// Go up
-			ansiCursorUp(26)
-			done := false
-			for !done {
-				select {
-				case lineFeeds := <-fe.extraLineFeeds:
-					ansiCursorUp(lineFeeds)
-				default:
-					done = true
-				}
-			}
-
-			fmt.Println(strings.Repeat("#", 44))
-
-			// See "Understand the Apple II", page 5-10
-			// http://www.applelogic.org/files/UNDERSTANDINGTHEAII.pdf
-			isAltText := fe.apple2.isApple2e && fe.apple2.io.isSoftSwitchActive(ioFlagAltChar)
-			var i, j, h, c uint8
-			// Top, middle and botton screen
-			for i = 0; i < 120; i = i + 40 {
-				// Memory pages
-				for j = 0x04; j < 0x08; j++ {
-					p := fe.apple2.mmu.physicalMainRAM[j]
-					// The two half pages
-					for _, h = range []uint8{0, 128} {
-						line := ""
-						for c = i + h; c < i+h+40; c++ {
-							line += textMemoryByteToString(p.internalPeek(c), isAltText)
-						}
-						fmt.Printf("# %v #\n", line)
-					}
-				}
-			}
-
-			fmt.Println(strings.Repeat("#", 44))
-			if fe.stdinKeyboard {
-				fmt.Print("\033[KLine: ")
-			}
-		}
-		time.Sleep(refreshDelayMs * time.Millisecond)
-	}
+func ansiCursorUp(steps int) string {
+	return fmt.Sprintf("\033[%vA", steps)
 }
 
 func (fe *ansiConsoleFrontend) textModeGoRoutine() {
 	fe.extraLineFeeds = make(chan int, 100)
 
-	fmt.Printf(strings.Repeat("\n", 26))
+	fmt.Printf(strings.Repeat("\n", textLines+3))
 	for {
-		if fe.textUpdated {
-			fe.textUpdated = false
 		// Go up
-			ansiCursorUp(26)
+		content := ansiCursorUp(textLines + 3)
 		done := false
 		for !done {
 			select {
 			case lineFeeds := <-fe.extraLineFeeds:
-					ansiCursorUp(lineFeeds)
+				content += ansiCursorUp(lineFeeds)
 			default:
 				done = true
 			}
 		}
 
+		content += "\n"
+		content += fmt.Sprintln(strings.Repeat("#", textColumns+4))
+
 		pageIndex := 0
 		if fe.apple2.io.isSoftSwitchActive(ioFlagSecondPage) {
 			pageIndex = 1
 		}
 		isAltText := fe.apple2.isApple2e && fe.apple2.io.isSoftSwitchActive(ioFlagAltChar)
 
-			fmt.Println(strings.Repeat("#", 44))
-			for line := 0; line < 24; line++ {
-				text := ""
-				for col := 0; col < 40; col++ {
-					value := getTextChar(fe.apple2, col, line, pageIndex)
-					text += textMemoryByteToString(value, isAltText)
+		for l := 0; l < textLines; l++ {
+			line := ""
+			for c := 0; c < textColumns; c++ {
+				char := getTextChar(fe.apple2, c, l, pageIndex)
+				line += textMemoryByteToString(char, isAltText)
 			}
-				fmt.Printf("# %v #\n", text)
+			content += fmt.Sprintf("# %v #\n", line)
 		}
 
-			fmt.Println(strings.Repeat("#", 44))
+		content += fmt.Sprintln(strings.Repeat("#", textColumns+4))
 		if fe.stdinKeyboard {
-				fmt.Print("\033[KLine: ")
+			content += "\033[KLine: "
 		}
 
-			//saveSnapshot(fe.apple2)
+		if content != fe.lastContent {
+			fmt.Print(content)
+			fe.lastContent = content
 		}
 		time.Sleep(refreshDelayMs * time.Millisecond)
 	}

apple2/apple2.go

@@ -3,7 +3,6 @@ package apple2
 import (
 	"fmt"
 	"go6502/core6502"
-	"io/ioutil"
 	"time"
 )
 
@@ -36,11 +35,10 @@ func NewApple2(romFile string, charRomFile string, clockMhz float64,
 	var a Apple2
 	a.mmu = newMemoryManager(&a)
 	a.cpu = core6502.NewNMOS6502(a.mmu)
-	a.loadRom(romFile)
+	a.mmu.loadRom(romFile)
 	if charRomFile != "" {
 		a.cg = NewCharacterGenerator(charRomFile)
 	}
-	a.mmu.resetRomPaging()
 	a.commandChannel = make(chan int, 100)
 	a.isColor = isColor
 	a.fastMode = fastMode
@@ -182,32 +180,3 @@ func (a *Apple2) releaseFastMode() {
 		a.fastRequestsCounter--
 	}
 }
-
-func (a *Apple2) loadRom(filename string) {
-	bytes, err := ioutil.ReadFile(filename)
-	if err != nil {
-		panic(err)
-	}
-	size := len(bytes)
-	if size != apple2RomSize && size != apple2eRomSize {
-		panic("Rom size not supported")
-	}
-
-	romStart := 0
-	if size == apple2eRomSize {
-		// The extra 4kb ROM is first in the rom file.
-		// It starts with 256 unused bytes not mapped to 0xc000.
-		a.isApple2e = true
-		extraRomSize := apple2eRomSize - apple2RomSize
-		a.mmu.physicalROMe = make([]romPage, extraRomSize>>8)
-		for i := 0; i < extraRomSize; i++ {
-			a.mmu.physicalROMe[i>>8].burn(uint8(i), bytes[i])
-		}
-		romStart = extraRomSize
-	}
-
-	a.mmu.physicalROM = make([]romPage, apple2RomSize>>8)
-	for i := 0; i < apple2RomSize; i++ {
-		a.mmu.physicalROM[i>>8].burn(uint8(i), bytes[i+romStart])
-	}
-}

apple2/cardBase.go

@@ -2,7 +2,7 @@ package apple2
 
 type cardBase struct {
 	a    *Apple2
-	rom  []memoryPage
+	rom  *memoryRange
 	slot int
 	ssr  [16]softSwitchR
 	ssw  [16]softSwitchW
@@ -11,8 +11,9 @@ type cardBase struct {
 func (c *cardBase) insert(a *Apple2, slot int) {
 	c.a = a
 	c.slot = slot
-	if slot != 0 && c.rom[0] != nil {
-		a.mmu.setPage(uint8(0xC0+slot), c.rom[0])
+	if slot != 0 && c.rom != nil {
+		c.rom.base = uint16(0xC000 + slot*0x100)
+		a.mmu.setPage(uint8(0xC0+slot), c.rom)
 	}
 
 	for i := 0; i < 0x10; i++ {

apple2/cardDisk2.go

@@ -30,7 +30,7 @@ type cardDisk2Drive struct {
 
 func newCardDisk2(filename string) *cardDisk2 {
 	var c cardDisk2
-	c.rom = loadCardRom(filename)
+	c.rom = newMemoryRange(0, loadCardRom(filename))
 
 	// Phase control soft switches
 	// Lazy emulation. It only checks for phases on and move the head
@@ -137,29 +137,12 @@ func newCardDisk2(filename string) *cardDisk2 {
 	return &c
 }
 
-func loadCardRom(filename string) []memoryPage {
-	bytes, err := ioutil.ReadFile(filename)
+func loadCardRom(filename string) []uint8 {
+	data, err := ioutil.ReadFile(filename)
 	if err != nil {
 		panic(err)
 	}
-
-	size := len(bytes)
-	pages := size / 256
-	if (size % 256) > 0 {
-		pages++
-	}
-
-	rom := make([]romPage, pages)
-	for i := 0; i < size; i++ {
-		rom[i>>8].burn(uint8(i), bytes[i])
-	}
-
-	memPages := make([]memoryPage, pages)
-	for i := range rom {
-		memPages[i] = &rom[i]
-	}
-
-	return memPages
+	return data
 }
 
 func (d *cardDisk2Drive) insertDiskette(dt *diskette16sector) {

apple2/diskette16sector.go

@@ -1,6 +1,7 @@
 package apple2
 
 import (
+	"io/ioutil"
 	"os"
 )
 
@@ -33,41 +34,25 @@ func (d *diskette16sector) read(track int, position int) (value uint8, newPositi
 func loadDisquette(filename string) *diskette16sector {
 	var d diskette16sector
 
-	f, err := os.Open(filename)
+	data, err := ioutil.ReadFile(filename)
 	if err != nil {
 		panic(err)
 	}
-	defer f.Close()
+	size := len(data)
 
-	stats, statsErr := f.Stat()
-	if statsErr != nil {
-		panic(err)
-	}
-
-	size := stats.Size()
 	if size == nibImageSize {
 		// Load file already in nib format
 		for i := 0; i < numberOfTracks; i++ {
-			d.track[i] = make([]byte, nibBytesPerTrack)
-			n, err := f.Read(d.track[i])
-			if err != nil || n != nibBytesPerTrack {
-				panic("Error loading file")
-			}
+			d.track[i] = data[nibBytesPerTrack*i : nibBytesPerTrack*(i+1)]
 		}
 	} else if size == dskImageSize {
-		// Load file in dsk format
-		data := make([]byte, dskImageSize)
-		n, err := f.Read(data)
-		if err != nil || n != dskImageSize {
-			panic("Error loading file")
-		}
 		// Convert to nib
 		for i := 0; i < numberOfTracks; i++ {
 			trackData := data[i*bytesPerTrack : (i+1)*bytesPerTrack]
 			d.track[i] = nibEncodeTrack(trackData, defaultVolumeTag, byte(i))
 		}
 	} else {
-		panic("Disk size with nib format has to be 232960 bytes")
+		panic("Invalid disk size")
 	}
 
 	return &d

apple2/ioC0Page.go

@@ -80,32 +80,26 @@ func (p *ioC0Page) setSpeakerProvider(s SpeakerProvider) {
 	p.speaker = s
 }
 
-func (p *ioC0Page) Peek(address uint8) uint8 {
+func (p *ioC0Page) peek(address uint16) uint8 {
 	//fmt.Printf("Peek on $C0%02x ", address)
-	ss := p.softSwitchesR[address]
+	pageAddress := uint8(address)
+	ss := p.softSwitchesR[pageAddress]
 	if ss == nil {
 		if p.apple2.panicSS {
-			panic(fmt.Sprintf("Unknown softswitch on read to 0xC0%02x", address))
+			panic(fmt.Sprintf("Unknown softswitch on read to 0xC0%02x", pageAddress))
 		}
 		return 0
 	}
 	return ss(p)
 }
 
-func (p *ioC0Page) internalPeek(address uint8) uint8 {
-	return 0
-}
-
-func (p *ioC0Page) all() []uint8 {
-	return nil
-}
-
-func (p *ioC0Page) Poke(address uint8, value uint8) {
+func (p *ioC0Page) poke(address uint16, value uint8) {
 	//fmt.Printf("Poke on $C0%02x with %02x ", address, value)
-	ss := p.softSwitchesW[address]
+	pageAddress := uint8(address)
+	ss := p.softSwitchesW[pageAddress]
 	if ss == nil {
 		if p.apple2.panicSS {
-			panic(fmt.Sprintf("Unknown softswitch on write to 0xC0%02x", address))
+			panic(fmt.Sprintf("Unknown softswitch on write to 0xC0%02x", pageAddress))
 		}
 		return
 	}

apple2/memoryManager.go

@@ -1,26 +1,25 @@
 package apple2
 
+import "io/ioutil"
+
 // See https://fabiensanglard.net/fd_proxy/prince_of_persia/Inside%20the%20Apple%20IIe.pdf
 // See https://i.stack.imgur.com/yn21s.gif
 
 type memoryManager struct {
 	apple2 *Apple2
 	// Map of assigned pages
-	activeMemory [256]memoryPage
+	activeMemoryRead  [256]memoryHandler
+	activeMemoryWrite [256]memoryHandler
 
 	// Pages prepared to be paged in and out
-	physicalMainRAM        []ramPage        // 0x0000 to 0xbfff, Up to 48 Kb
-	physicalROM            []romPage        // 0xd000 to 0xffff, 12 Kb
-	physicalROMe           []romPage        // 0xc000 to 0xcfff, Zero or 4bk in the Apple2e
-	unassignedExpansionROM []unassignedPage // 0xc000 to 0xcfff
+	physicalMainRAM *memoryRange // 0x0000 to 0xbfff, Up to 48 Kb
+	physicalROM     *memoryRange // 0xd000 to 0xffff, 12 Kb
+	physicalROMe    *memoryRange // 0xc000 to 0xcfff, Zero or 4bk in the Apple2e
 }
 
-// memoryPage is a data page of 256 bytes
-type memoryPage interface {
-	Peek(uint8) uint8
-	Poke(uint8, uint8)
-	internalPeek(uint8) uint8
-	all() []uint8
+type memoryHandler interface {
+	peek(uint16) uint8
+	poke(uint16, uint8)
 }
 
 const (
@@ -34,18 +33,11 @@ func (mmu *memoryManager) Peek(address uint16) uint8 {
 	}
 
 	hi := uint8(address >> 8)
-	lo := uint8(address)
-	return mmu.activeMemory[hi].Peek(lo)
-}
-
-func (mmu *memoryManager) internalPeek(address uint16) uint8 {
-	hi := uint8(address >> 8)
-	lo := uint8(address)
-	return mmu.activeMemory[hi].internalPeek(lo)
-}
-
-func (mmu *memoryManager) internalPage(hi uint8) []uint8 {
-	return mmu.activeMemory[hi].all()
+	mh := mmu.activeMemoryRead[hi]
+	if mh == nil {
+		return 0xf4 // Or some random number
+	}
+	return mh.peek(address)
 }
 
 // Poke sets the data at the given address
@@ -54,15 +46,24 @@ func (mmu *memoryManager) Poke(address uint16, value uint8) {
 		mmu.resetSlotExpansionRoms()
 	}
 	hi := uint8(address >> 8)
-	lo := uint8(address)
-	mmu.activeMemory[hi].Poke(lo, value)
+	mh := mmu.activeMemoryWrite[hi]
+	if mh == nil {
+		return
+	}
+	mh.poke(address, value)
 }
 
-// SetPage assigns a MemoryPage implementation on the page given
-func (mmu *memoryManager) setPage(index uint8, page memoryPage) {
-	//fmt.Printf("Assigning page 0x%02x type %s\n", index, reflect.TypeOf(page))
-	mmu.activeMemory[index] = page
+func (mmu *memoryManager) setPage(index uint8, mh memoryHandler) {
+	mmu.setPageRead(index, mh)
+	mmu.setPageWrite(index, mh)
+}
 
+func (mmu *memoryManager) setPageRead(index uint8, mh memoryHandler) {
+	mmu.activeMemoryRead[index] = mh
+}
+
+func (mmu *memoryManager) setPageWrite(index uint8, mh memoryHandler) {
+	mmu.activeMemoryWrite[index] = mh
 }
 
 // When 0xcfff is accessed the card expansion rom is unassigned
@@ -71,9 +72,8 @@ func (mmu *memoryManager) resetSlotExpansionRoms() {
 		// Ignore if the Apple2 shadow ROM is active
 		return
 	}
-	for i := 8; i < 16; i++ {
-		p := mmu.unassignedExpansionROM[i]
-		mmu.setPage(uint8(i+0xc0), &p)
+	for i := uint8(0xc8); i < 0xd0; i++ {
+		mmu.setPage(i, nil)
 	}
 }
 
@@ -82,25 +82,43 @@ func newMemoryManager(a *Apple2) *memoryManager {
 	mmu.apple2 = a
 
 	// Assign RAM from 0x0000 to 0xbfff, 48kb
-	mmu.physicalMainRAM = make([]ramPage, 0xc0)
-	for i := 0; i <= 0xbf; i++ {
-		mmu.setPage(uint8(i), &(mmu.physicalMainRAM[i]))
+	ram := make([]uint8, 0xc000)
+	mmu.physicalMainRAM = newMemoryRange(0, ram)
+	for i := 0; i < 0xc000; i = i + 0x100 {
+		mmu.setPage(uint8(i>>8), mmu.physicalMainRAM)
 	}
 
-	// Set the 0xc100 to 0xcfff as unasigned, 4kb. It wil be taken by slot cards.
-	mmu.unassignedExpansionROM = make([]unassignedPage, 0x10)
-	for i := 1; i < 0x10; i++ {
-		page := uint8(i + 0xc0)
-		p := &mmu.unassignedExpansionROM[i]
-		p.page = page
-		mmu.setPage(page, p)
-	}
 	return &mmu
 }
 
+func (mmu *memoryManager) loadRom(filename string) {
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		panic(err)
+	}
+	size := len(data)
+	if size != apple2RomSize && size != apple2eRomSize {
+		panic("Rom size not supported")
+	}
+
+	a := mmu.apple2
+	romStart := 0
+	if size == apple2eRomSize {
+		// The extra 4kb ROM is first in the rom file.
+		// It starts with 256 unused bytes not mapped to 0xc000.
+		a.isApple2e = true
+		extraRomSize := apple2eRomSize - apple2RomSize
+		a.mmu.physicalROMe = newMemoryRange(0xc000, data[0:extraRomSize])
+		romStart = extraRomSize
+	}
+
+	a.mmu.physicalROM = newMemoryRange(0xd000, data[romStart:])
+	mmu.resetRomPaging()
+}
+
 func (mmu *memoryManager) resetRomPaging() {
 	// Assign the first 12kb of ROM from 0xd000 to 0xfff
-	for i := 0xd0; i <= 0xff; i++ {
-		mmu.setPage(uint8(i), &(mmu.physicalROM[i-0xd0]))
+	for i := 0x0000; i < 0x3000; i = i + 0x100 {
+		mmu.setPageRead(uint8(0xd0+(i>>8)), mmu.physicalROM)
 	}
 }

apple2/memoryRange.go

@@ -0,0 +1,25 @@
+package apple2
+
+type memoryRange struct {
+	base uint16
+	data []uint8
+}
+
+func newMemoryRange(base uint16, data []uint8) *memoryRange {
+	var m memoryRange
+	m.base = base
+	m.data = data
+	return &m
+}
+
+func (m *memoryRange) peek(address uint16) uint8 {
+	return m.data[address-m.base]
+}
+
+func (m *memoryRange) poke(address uint16, value uint8) {
+	m.data[address-m.base] = value
+}
+
+func (m *memoryRange) subRange(a, b uint16) []uint8 {
+	return m.data[a-m.base : b-m.base]
+}

apple2/rxmPage.go

@@ -1,46 +0,0 @@
-package apple2
-
-type rxmPage struct {
-	data     [256]uint8
-	observer func(address uint8, isWrite bool)
-}
-
-type ramPage struct {
-	rxmPage
-}
-
-type romPage struct {
-	rxmPage
-}
-
-func (p *rxmPage) Peek(address uint8) uint8 {
-	p.touch(address, false)
-	return p.data[address]
-}
-
-func (p *rxmPage) internalPeek(address uint8) uint8 {
-	return p.data[address]
-}
-
-func (p *rxmPage) all() []uint8 {
-	return p.data[:]
-}
-
-func (p *rxmPage) Poke(address uint8, value uint8) {
-	p.touch(address, true)
-	p.data[address] = value
-}
-
-func (p *rxmPage) touch(address uint8, isWrite bool) {
-	if p.observer != nil {
-		p.observer(address, isWrite)
-	}
-}
-
-func (p *romPage) Poke(address uint8, value uint8) {
-	// Do nothing
-}
-
-func (p *romPage) burn(address uint8, value uint8) {
-	p.data[address] = value
-}

apple2/screenHiRes.go

@@ -30,11 +30,7 @@ func getHiResLine(a *Apple2, line int, page int) []uint8 {
 	}
 
 	address += getHiResLineOffset(line)
-	hi := uint8(address >> 8)
-	lo := uint8(address)
-
-	memPage := a.mmu.internalPage(hi)
-	return memPage[lo : lo+40]
+	return a.mmu.physicalMainRAM.subRange(address, address+40)
 }
 
 func snapshotHiResModeMonoShift(a *Apple2, page int, mixedMode bool, light color.Color) *image.RGBA {

apple2/screenText.go

@@ -31,7 +31,7 @@ func getTextChar(a *Apple2, col int, line int, page int) uint8 {
 		address = textPage2Address
 	}
 	address += getTextCharOffset(col, line)
-	return a.mmu.internalPeek(address)
+	return a.mmu.physicalMainRAM.subRange(address, address+1)[0]
 }
 
 func snapshotTextMode(a *Apple2, page int, mixMode bool, light color.Color) *image.RGBA {

apple2/softSwitches2e.go

@@ -46,8 +46,8 @@ func getSoftSwitchExt(ioFlag uint8, dstValue uint8, action softSwitchExtAction)
 
 func softSwitchIntCxRomOn(io *ioC0Page) {
 	mmu := io.apple2.mmu
-	for i := uint8(1); i < 16; i++ {
-		mmu.setPage(uint8(0xc0+i), &mmu.physicalROMe[i])
+	for i := 0x100; i < 0x1000; i = i + 0x100 {
+		mmu.setPage(uint8(i>>8), mmu.physicalROMe)
 	}
 }
 
@@ -55,7 +55,7 @@ func softSwitchIntCxRomOff(io *ioC0Page) {
 	// TODO restore all the ROM from the slot for 0xc1 to 0xc7
 	mmu := io.apple2.mmu
 	for i := 1; i < 16; i++ {
-		mmu.setPage(uint8(0xc0+i), &mmu.unassignedExpansionROM[i])
+		mmu.setPage(uint8(0xc0+i), nil)
 	}
 }
 
@@ -65,13 +65,13 @@ func softSwitchSlotC3RomOn(io *ioC0Page) {
 	}
 	// TODO restore the slot 3 ROM
 	mmu := io.apple2.mmu
-	mmu.setPage(0xC3, &mmu.unassignedExpansionROM[3])
+	mmu.setPage(0xC3, nil)
 }
 
 func softSwitchSlotC3RomOff(io *ioC0Page) {
 	if io.isSoftSwitchActive(ioFlagIntCxRom) {
-		return // Ignore if allt the Apple2 shadow ROM is active
+		return // Ignore if alt the Apple2 shadow ROM is active
 	}
 	mmu := io.apple2.mmu
-	mmu.setPage(0xC3, &mmu.physicalROMe[3])
+	mmu.setPageRead(0xC3, mmu.physicalROMe)
 }

apple2/unassignedPage.go

@@ -1,24 +0,0 @@
-package apple2
-
-type unassignedPage struct {
-	page uint8
-}
-
-func (p *unassignedPage) Peek(address uint8) uint8 {
-	//fmt.Printf("Read on address 0x%02x%02x\n", p.page, address)
-	//panic(address)
-	return 0xdd
-}
-
-func (p *unassignedPage) internalPeek(address uint8) uint8 {
-	return 0xdd
-}
-
-func (p *unassignedPage) all() []uint8 {
-	return nil
-}
-
-func (p *unassignedPage) Poke(address uint8, value uint8) {
-	//fmt.Printf("Write on address 0x%02x%02x\n", p.page, address)
-	//panic(address)
-}