Observers on memory pages. Text memory is now regular RAM with an observer

apple2/ansiConsoleFrontend.go

@@ -21,12 +21,23 @@ type ansiConsoleFrontend struct {
 	mmu            *memoryManager
 	keyChannel     chan uint8
 	extraLineFeeds chan int
+	textUpdated    bool
 }
 
-func newAnsiConsoleFrontend(mmu *memoryManager) ansiConsoleFrontend {
+func newAnsiConsoleFrontend(mmu *memoryManager) *ansiConsoleFrontend {
 	var fe ansiConsoleFrontend
 	fe.mmu = mmu
-	return fe
+	fe.subscribeToTextPages()
+	return &fe
+}
+
+func (fe *ansiConsoleFrontend) subscribeToTextPages() {
+	observer := func(_ uint8, _ bool) {
+		fe.textUpdated = true
+	}
+	for i := 0x04; i < 0x08; i++ {
+		fe.mmu.physicalMainRAM[i].observer = observer
+	}
 }
 
 const refreshDelayMs = 100
@@ -37,7 +48,8 @@ func (fe *ansiConsoleFrontend) getKey() (key uint8, ok bool) {
 		for {
 			byte, err := reader.ReadByte()
 			if err != nil {
-				panic(err)
+				fmt.Println(err)
+				return
 			}
 			c <- byte
 		}
@@ -67,12 +79,13 @@ func ansiCursorUp(steps int) {
 	fmt.Printf("\033[%vA", steps)
 }
 
-func (fe *ansiConsoleFrontend) textModeGoRoutine(tp *textPages) {
+func (fe *ansiConsoleFrontend) textModeGoRoutine() {
 	fe.extraLineFeeds = make(chan int, 100)
 
 	fmt.Printf(strings.Repeat("\n", 26))
 	for {
-		if tp.strobe() {
+		if fe.textUpdated {
+			fe.textUpdated = false
 			// Go up
 			ansiCursorUp(26)
 			done := false
@@ -90,16 +103,17 @@ func (fe *ansiConsoleFrontend) textModeGoRoutine(tp *textPages) {
 			// See "Understand the Apple II", page 5-10
 			// http://www.applelogic.org/files/UNDERSTANDINGTHEAII.pdf
 			isAltText := fe.mmu.isApple2e && fe.mmu.ioPage.isSoftSwitchExtActive(ioFlagAltChar)
-			var i, j, h uint8
+			var i, j, h, c uint8
 			// Top, middle and botton screen
 			for i = 0; i < 120; i = i + 40 {
 				// Memory pages
-				for _, p := range tp.pages {
+				for j = 0x04; j < 0x08; j++ {
+					p := fe.mmu.physicalMainRAM[j]
 					// The two half pages
 					for _, h = range []uint8{0, 128} {
 						line := ""
-						for j = i + h; j < i+h+40; j++ {
-							line += textMemoryByteToString(p.Peek(j), isAltText)
+						for c = i + h; c < i+h+40; c++ {
+							line += textMemoryByteToString(p.internalPeek(c), isAltText)
 						}
 						fmt.Printf("# %v #\n", line)
 					}

apple2/apple2.go

@@ -10,8 +10,8 @@ func Run(romFile string, log bool) {
 	s.Mem = mmu
 
 	fe := newAnsiConsoleFrontend(mmu)
-	mmu.ioPage.setKeyboardProvider(&fe)
-	go fe.textModeGoRoutine(mmu.textPages1)
+	mmu.ioPage.setKeyboardProvider(fe)
+	go fe.textModeGoRoutine()
 
 	// Start the processor
 	core6502.Reset(&s)

apple2/memoryManager.go

@@ -18,8 +18,7 @@ type memoryManager struct {
 	unassignedExpansionROM []unassignedPage // 0xc000 to 0xcfff
 	ioPage                 *ioC0Page        // 0xc000 to 0xc080
 	isApple2e              bool
-	textPages1             *textPages // 0x0400 to 0x07ff
-	activeSlow             int        // Slot that has the addressing 0xc800 to 0ccfff
+	activeSlot             int // Slot that has the addressing 0xc800 to 0ccfff
 }
 
 const (
@@ -87,14 +86,6 @@ func newAddressSpace(romImage string) *memoryManager {
 		m.SetPage(page, p)
 	}
 
-	// Replace RAM in the TEXT1 area.
-	// TODO: treat as normal ram. Add is dirty in all RAM pages
-	var t textPages
-	mmu.textPages1 = &t
-	for i := 0; i < 4; i++ {
-		m.SetPage(uint8(4+i), &(t.pages[i]))
-	}
-
 	return &mmu
 }
 

apple2/rxmPage.go

@@ -1,23 +1,36 @@
 package apple2
 
-type ramPage struct {
+type rxmPage struct {
 	data     [256]uint8
+	observer func(address uint8, isWrite bool)
+}
+
+type ramPage struct {
+	rxmPage
 }
 
 type romPage struct {
-	data [256]uint8
+	rxmPage
 }
 
-func (p *ramPage) Peek(address uint8) uint8 {
+func (p *rxmPage) Peek(address uint8) uint8 {
+	p.touch(address, false)
 	return p.data[address]
 }
 
-func (p *ramPage) Poke(address uint8, value uint8) {
+func (p *rxmPage) internalPeek(address uint8) uint8 {
+	return p.data[address]
+}
+
+func (p *rxmPage) Poke(address uint8, value uint8) {
+	p.touch(address, true)
 	p.data[address] = value
 }
 
-func (p *romPage) Peek(address uint8) uint8 {
-	return p.data[address]
+func (p *rxmPage) touch(address uint8, isWrite bool) {
+	if p.observer != nil {
+		p.observer(address, isWrite)
+	}
 }
 
 func (p *romPage) Poke(address uint8, value uint8) {

apple2/textPages.go

@@ -1,48 +0,0 @@
-package apple2
-
-type textPages struct {
-	pages [4]textPage
-}
-
-type textPage struct {
-	dirty bool
-	data  [256]uint8
-}
-
-func (p *textPage) Peek(address uint8) uint8 {
-	return p.data[address]
-}
-
-func (p *textPage) Poke(address uint8, value uint8) {
-	p.data[address] = value
-	// Note: we could avoid setting dirty on the 16 blocks of 8 hidden bytes
-	p.dirty = true
-}
-
-func (tp *textPages) read(column uint8, line uint8) uint8 {
-	page, address := tp.charAddress(column, line)
-	return tp.pages[page].Peek(address)
-}
-
-func (tp *textPages) write(column uint8, line uint8, value uint8) {
-	page, address := tp.charAddress(column, line)
-	tp.pages[page].Poke(address, value)
-}
-
-func (tp *textPages) charAddress(column uint8, line uint8) (page uint8, address uint8) {
-	page = (line % 8) / 2
-	address = column + (line/8)*40 + (line%2)*128
-	return
-}
-
-func (tp *textPages) strobe() bool {
-	// Thread safe. May just mark more dirties than needed.
-	dirty := false
-	for i := 0; i < 4; i++ {
-		if tp.pages[i].dirty {
-			dirty = true
-			tp.pages[i].dirty = false
-		}
-	}
-	return dirty
-}

apple2/textPages_test.go

@@ -1,23 +0,0 @@
-package apple2
-
-import "testing"
-
-func TestCharAddress(t *testing.T) {
-	var tp textPages
-
-	mappings := [][]uint8{
-		// column, line, page, address
-		{0, 0, 0, 0},
-		{0, 1, 0, 0x80},
-		{0, 2, 1, 0x00},
-		{0, 23, 3, 0xD0},
-	}
-
-	for _, v := range mappings {
-		page, address := tp.charAddress(v[0], v[1])
-		if page != v[2] || address != v[3] {
-			t.Errorf("Error on charAddress for (%v, %v) (%v:%02x) <> (%v:%02x)",
-				v[0], v[1], v[2], v[3], page, address)
-		}
-	}
-}

main.go

@@ -4,8 +4,8 @@ import "go6502/apple2"
 
 func main() {
 	//romFile := "apple2/romdumps/Apple2.rom"
-	//romFile := "apple2/romdumps/Apple2_Plus.rom"
-	romFile := "apple2/romdumps/Apple2e.rom"
+	romFile := "apple2/romdumps/Apple2_Plus.rom"
+	//romFile := "apple2/romdumps/Apple2e.rom"
 
 	log := false
 	apple2.Run(romFile, log)