Support for the 16KB language card

apple2/apple2.go

@@ -53,7 +53,7 @@ func NewApple2(romFile string, charRomFile string, clockMhz float64,
 
 	// Set the io in 0xc000
 	a.io = newIoC0Page(&a)
-	a.mmu.setPage(0xc0, a.io)
+	a.mmu.setPages(0xc0, 0xc0, a.io)
 
 	return &a
 }
@@ -70,6 +70,13 @@ func (a *Apple2) AddDisk2(slot int, diskRomFile string, diskImage string) {
 	}
 }
 
+// AddLanguageCard inserts a 16Kb card
+func (a *Apple2) AddLanguageCard(slot int) {
+	d := newCardLanguage()
+	d.cardBase.insert(a, slot)
+	d.applyState()
+}
+
 // ConfigureStdConsole uses stdin and stdout to interface with the Apple2
 func (a *Apple2) ConfigureStdConsole(stdinKeyboard bool, stdoutScreen bool) {
 	if !stdinKeyboard && !stdoutScreen {

apple2/cardBase.go

@@ -12,8 +12,8 @@ func (c *cardBase) insert(a *Apple2, slot int) {
 	c.a = a
 	c.slot = slot
 	if slot != 0 && c.rom != nil {
-		c.rom.base = uint16(0xC000 + slot*0x100)
-		a.mmu.setPage(uint8(0xC0+slot), c.rom)
+		c.rom.base = uint16(0xc000 + slot*0x100)
+		a.mmu.setPagesRead(uint8(0xc0+slot), uint8(0xc0+slot), c.rom)
 	}
 
 	for i := 0; i < 0x10; i++ {

apple2/cardLanguage.go

@@ -0,0 +1,120 @@
+package apple2
+
+/*
+Language card with 16 extra kb for the Apple ][ and  ][+
+Manual: http://www.applelogic.org/files/LANGCARDMAN.pdf
+
+The language card doesn't have ROM for Cx00. It would not
+be used in slot 0 anyway.
+
+Note also that language cards for the Apple ][ had ROM on
+board to replace the main board F8 ROM with Autostart. That
+was not used/needed on the Apple ][+. As this emulates the
+Apple ][+, it is not considered. For the PLus it is often
+refered as Language card but it is really a 16 KB Ram card,
+
+
+"When RAM is deselected, the ROM on the LAnguage card is selected for
+the top 2K ($F800-$FFFF), and the ROM on the main board is selected
+for $D000-$F7FF.
+
+Power on RESET initializes ROM to read mode and RAM to write mode,
+and selects the second 4K bank to map $D000-$DFFF."
+
+*/
+
+type cardLanguage struct {
+	cardBase
+	readState  bool
+	writeState int
+	activeBank int
+	ramBankA   *memoryRange // First 4kb to map in 0xD000-0xDFFF
+	ramBankB   *memoryRange // Second 4kb to map in 0xD000-0xDFFF
+	ramUpper   *memoryRange // Upper 8kb to map in 0xE000-0xFFFF
+}
+
+const (
+	// Write enabling requires two sofstwitch accesses
+	lcWriteDisabled    = 0
+	lcWriteHalfEnabled = 1
+	lcWriteEnabled     = 2
+)
+
+func newCardLanguage() *cardLanguage {
+	var c cardLanguage
+	c.readState = false
+	c.writeState = lcWriteEnabled
+	c.activeBank = 1
+
+	c.ramBankA = newMemoryRange(0xd000, make([]uint8, 0x1000))
+	c.ramBankB = newMemoryRange(0xd000, make([]uint8, 0x1000))
+	c.ramUpper = newMemoryRange(0xe000, make([]uint8, 0x2000))
+
+	for i := 0x0; i <= 0xf; i++ {
+		iCopy := i
+		c.ssr[i] = func(*ioC0Page) uint8 {
+			c.ssAction(iCopy)
+			return 0
+		}
+		c.ssw[i] = func(*ioC0Page, uint8) {
+			// Writing resets write count (from A2AUDIT)
+			c.writeState = lcWriteDisabled
+		}
+	}
+	return &c
+}
+
+func (c *cardLanguage) ssAction(ss int) {
+	c.activeBank = (ss >> 3) & 1
+	action := ss & 0x3
+	switch action {
+	case 0:
+		// RAM read, no writes
+		c.readState = true
+		c.writeState = lcWriteDisabled
+	case 1:
+		// ROM read, RAM write
+		c.readState = false
+		c.writeState++
+	case 2:
+		// ROM read, no writes
+		c.readState = false
+		c.writeState = lcWriteDisabled
+	case 3:
+		//RAM read, RAM write
+		c.readState = true
+		c.writeState++
+	}
+
+	if c.writeState > lcWriteEnabled {
+		c.writeState = lcWriteEnabled
+	}
+
+	c.applyState()
+}
+
+func (c *cardLanguage) getActiveBank() *memoryRange {
+	if c.activeBank == 0 {
+		return c.ramBankA
+	}
+	return c.ramBankB
+}
+
+func (c *cardLanguage) applyState() {
+	mmu := c.a.mmu
+
+	if c.readState {
+		mmu.setPagesRead(0xd0, 0xdf, c.getActiveBank())
+		mmu.setPagesRead(0xe0, 0xff, c.ramUpper)
+	} else {
+		mmu.setPagesRead(0xd0, 0xff, mmu.physicalROM)
+	}
+
+	if c.writeState == lcWriteEnabled {
+		mmu.setPagesWrite(0xd0, 0xdf, c.getActiveBank())
+		mmu.setPagesWrite(0xe0, 0xff, c.ramUpper)
+	} else {
+		mmu.setPagesWrite(0xd0, 0xff, nil)
+	}
+
+}

apple2/ioC0Page.go

@@ -81,7 +81,7 @@ func (p *ioC0Page) setSpeakerProvider(s SpeakerProvider) {
 }
 
 func (p *ioC0Page) peek(address uint16) uint8 {
-	//fmt.Printf("Peek on $C0%02x ", address)
+	//fmt.Printf("Peek on $%02x\n", address)
 	pageAddress := uint8(address)
 	ss := p.softSwitchesR[pageAddress]
 	if ss == nil {
@@ -94,7 +94,7 @@ func (p *ioC0Page) peek(address uint16) uint8 {
 }
 
 func (p *ioC0Page) poke(address uint16, value uint8) {
-	//fmt.Printf("Poke on $C0%02x with %02x ", address, value)
+	//fmt.Printf("Poke on $%02x with %02x\n", address, value)
 	pageAddress := uint8(address)
 	ss := p.softSwitchesW[pageAddress]
 	if ss == nil {

apple2/memoryManager.go

@@ -1,6 +1,8 @@
 package apple2
 
-import "io/ioutil"
+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
@@ -53,17 +55,31 @@ func (mmu *memoryManager) Poke(address uint16, value uint8) {
 	mh.poke(address, value)
 }
 
-func (mmu *memoryManager) setPage(index uint8, mh memoryHandler) {
-	mmu.setPageRead(index, mh)
-	mmu.setPageWrite(index, mh)
+func (mmu *memoryManager) setPages(begin uint8, end uint8, mh memoryHandler) {
+	mmu.setPagesRead(begin, end, mh)
+	mmu.setPagesWrite(begin, end, mh)
 }
 
-func (mmu *memoryManager) setPageRead(index uint8, mh memoryHandler) {
-	mmu.activeMemoryRead[index] = mh
+func (mmu *memoryManager) setPagesRead(begin uint8, end uint8, mh memoryHandler) {
+	i := begin
+	for {
+		mmu.activeMemoryRead[i] = mh
+		if i == end {
+			break
+		}
+		i++
+	}
 }
 
-func (mmu *memoryManager) setPageWrite(index uint8, mh memoryHandler) {
-	mmu.activeMemoryWrite[index] = mh
+func (mmu *memoryManager) setPagesWrite(begin uint8, end uint8, mh memoryHandler) {
+	i := begin
+	for {
+		mmu.activeMemoryWrite[i] = mh
+		if i == end {
+			break
+		}
+		i++
+	}
 }
 
 // When 0xcfff is accessed the card expansion rom is unassigned
@@ -72,9 +88,7 @@ func (mmu *memoryManager) resetSlotExpansionRoms() {
 		// Ignore if the Apple2 shadow ROM is active
 		return
 	}
-	for i := uint8(0xc8); i < 0xd0; i++ {
-		mmu.setPage(i, nil)
-	}
+	mmu.setPagesRead(0xc8, 0xcf, nil)
 }
 
 func newMemoryManager(a *Apple2) *memoryManager {
@@ -84,9 +98,7 @@ func newMemoryManager(a *Apple2) *memoryManager {
 	// Assign RAM from 0x0000 to 0xbfff, 48kb
 	ram := make([]uint8, 0xc000)
 	mmu.physicalMainRAM = newMemoryRange(0, ram)
-	for i := 0; i < 0xc000; i = i + 0x100 {
-		mmu.setPage(uint8(i>>8), mmu.physicalMainRAM)
-	}
+	mmu.setPages(0x00, 0xc0, mmu.physicalMainRAM)
 
 	return &mmu
 }
@@ -119,6 +131,6 @@ func (mmu *memoryManager) loadRom(filename string) {
 func (mmu *memoryManager) resetRomPaging() {
 	// Assign the first 12kb of ROM from 0xd000 to 0xfff
 	for i := 0x0000; i < 0x3000; i = i + 0x100 {
-		mmu.setPageRead(uint8(0xd0+(i>>8)), mmu.physicalROM)
+		mmu.setPagesRead(0xd0, 0xff, mmu.physicalROM)
 	}
 }

apple2/softSwitches2e.go

@@ -45,33 +45,19 @@ func getSoftSwitchExt(ioFlag uint8, dstValue uint8, action softSwitchExtAction)
 }
 
 func softSwitchIntCxRomOn(io *ioC0Page) {
-	mmu := io.apple2.mmu
-	for i := 0x100; i < 0x1000; i = i + 0x100 {
-		mmu.setPage(uint8(i>>8), mmu.physicalROMe)
-	}
+	io.apple2.mmu.setPagesRead(0xc1, 0xcf, io.apple2.mmu.physicalROMe)
 }
 
 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), nil)
-	}
+	// TODO restore all the ROM from the slots for 0xc1 to 0xc7
+	io.apple2.mmu.setPages(0xc1, 0xc7, nil)
 }
 
 func softSwitchSlotC3RomOn(io *ioC0Page) {
-	if io.isSoftSwitchActive(ioFlagIntCxRom) {
-		return // Ignore if allt the Apple2 shadow ROM is active
-	}
 	// TODO restore the slot 3 ROM
-	mmu := io.apple2.mmu
-	mmu.setPage(0xC3, nil)
+	io.apple2.mmu.setPages(0xc3, 0xc3, nil)
 }
 
 func softSwitchSlotC3RomOff(io *ioC0Page) {
-	if io.isSoftSwitchActive(ioFlagIntCxRom) {
-		return // Ignore if alt the Apple2 shadow ROM is active
-	}
-	mmu := io.apple2.mmu
-	mmu.setPageRead(0xC3, mmu.physicalROMe)
+	io.apple2.mmu.setPagesRead(0xc3, 0xc3, io.apple2.mmu.physicalROMe)
 }

main.go

@@ -69,6 +69,7 @@ func main() {
 
 	log := false
 	a := apple2.NewApple2(*romFile, *charRomFile, *cpuClock, !*mono, *fastDisk, *panicSS)
+	a.AddLanguageCard(0)
 	if *disk2Slot > 0 {
 		a.AddDisk2(*disk2Slot, *disk2RomFile, *diskImage)
 	}