Swyftcard support (#13)

apple2Setup.go

@@ -191,6 +191,12 @@ func (a *Apple2) AddVidexCard(slot int) {
 	a.softVideoSwitch = NewSoftVideoSwitch(c)
 }
 
+// AddSwyftCard inserts a Swyft card in slot 3
+func (a *Apple2) AddSwyftCard() {
+	c := NewCardSwyft()
+	a.insertCard(c, 3)
+}
+
 // AddRGBCard inserts an RBG option to the Apple IIe 80 col 64KB card
 func (a *Apple2) AddRGBCard() {
 	setupRGBCard(a)

apple2Tester.go

@@ -35,3 +35,7 @@ func (at *apple2Tester) run() {
 func (at *apple2Tester) getText() string {
 	return screen.RenderTextModeString(at.a, false, false, false, at.a.isApple2e)
 }
+
+func (at *apple2Tester) getText80() string {
+	return screen.RenderTextModeString(at.a, true, false, false, at.a.isApple2e)
+}

apple2main.go

@@ -18,7 +18,7 @@ func MainApple() *Apple2 {
 		"slot for the disk driver. -1 for none.")
 	diskImage := flag.String(
 		"disk",
-		"<internal>/dos33.dsk",
+		defaultInternal,
 		"file to load on the first disk drive")
 	diskBImage := flag.String(
 		"diskb",
@@ -84,6 +84,10 @@ func MainApple() *Apple2 {
 		"videxCardSlot",
 		3,
 		"slot for the Videx Videoterm 80 columns card. For pre-2e models. -1 for none")
+	swyftCard := flag.Bool(
+		"swyftCard",
+		false,
+		"activate a Swyft Card in slot 3. Load the tutorial disk if none provided")
 	nsc := flag.Int(
 		"nsc",
 		-1,
@@ -169,6 +173,15 @@ func MainApple() *Apple2 {
 		}
 	}
 
+	// Resolve what is the default disk to use if not specified
+	if diskImageFinal == defaultInternal {
+		if *swyftCard {
+			diskImageFinal = "<internal>/SwyftWare_-_SwyftCard_Tutorial.woz"
+		} else {
+			diskImageFinal = "<internal>/dos33.dsk"
+		}
+	}
+
 	a := newApple2()
 	a.setup(*cpuClock, *fastDisk)
 	a.io.setTrace(*traceSS)
@@ -232,6 +245,12 @@ func MainApple() *Apple2 {
 	if *videxCardSlot > 0 {
 		a.AddVidexCard(*videxCardSlot)
 	}
+	if *swyftCard {
+		if !a.isApple2e {
+			panic("SwyftCard available only on Apple IIe or better")
+		}
+		a.AddSwyftCard()
+	}
 
 	if *smartPortImage != "" {
 		err := a.AddSmartPortDisk(5, *smartPortImage, *traceHD)
@@ -354,7 +373,7 @@ func initModel(a *Apple2, model string, romFile string, charRomFile string) {
 		panic("Model not supported")
 	}
 
-	// Load ROM if not loaded already
+	// Load ROM
 	if romFile != "" {
 		err := a.LoadRom(romFile)
 		if err != nil {
@@ -362,7 +381,7 @@ func initModel(a *Apple2, model string, romFile string, charRomFile string) {
 		}
 	}
 
-	// Load character generator if it loaded already
+	// Load character generator
 	cg, err := newCharacterGenerator(charRomFile, charGenMap, a.isApple2e)
 	if err != nil {
 		panic(err)

cardBase.go

@@ -114,6 +114,16 @@ func (c *cardBase) addCardSoftSwitchW(address uint8, ss softSwitchW, name string
 	c._sswName[address] = name
 }
 
+func (c *cardBase) addCardSoftSwitchRW(address uint8, ss softSwitchR, name string) {
+	c._ssr[address] = ss
+	c._ssrName[address] = name
+
+	c._ssw[address] = func(p *ioC0Page, _ uint8) {
+		ss(p)
+	}
+	c._sswName[address] = name
+}
+
 type softSwitches func(io *ioC0Page, address uint8, data uint8, write bool) uint8
 
 func (c *cardBase) addCardSoftSwitches(sss softSwitches, name string) {

cardSwyft.go

@@ -0,0 +1,133 @@
+package izapple2
+
+/*
+	Swyft card for Apple IIe
+
+See:
+	https://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Interface%20Cards/Other/IAI%20SwyftCard/
+
+*/
+
+/*
+"SwyftCard Hardware  Theory of Operation". SwyftCard manual, page 98:
+
+The SwyftCard is a plug-in card for the Apple /Ie that operates in
+slot 3. The card contains three integrated circuits which provide a
+power-on reset circuit, storage for the SwyftCard program, and control
+signals for the card. The card operates by asserting the Apple IIe bus
+signal INH' which disables the built-in ROM and enables the SwyftCard
+ROM. This permits the SwyftCard program to take over the system at
+power-on and run the SwyftCard program. (Please refer to the
+schematic.)
+
+The lM311 voltage comparator is connected to provide the power-on
+reset function. When the Apple lie is first turned on, the power-on
+reset circuit resets the PAL, turning on the SwyftCard and disabling
+the Apple IIe internal ROM. The power-on reset circuit must be
+provided because the existing Apple IIe reset function is used by
+many Apple lie programs for a "warm start": if Apple lie reset always
+started the SwyftCard, other programs could not use the "warm start."
+
+The 27128 PROM is used to store the SwyftCard program. The PROM
+contains 16384 bytes which are mapped into the address space
+$DOOO - $FFFF. Since the address space is only 12 Kbytes, there are
+two 4 Kbyte sections of the PROM mapped into the address space
+$DOOO-$DFFF.
+
+The card is controlled by the PAL. When the SwyftCard is active, the
+PAL asserts the INH' signal, enables the PROM, and bank switches
+the $DOOO-$DFFF address space. The card is controlled by two soft
+switches. The soft switches are controlled by accessing the following
+memory locations with either a read or a write operation.
+
+	$COBO - SwyftCard active, Bank 1
+	$COB1 - SwyftCard inactive, Bank 1
+	$COB2 - SwyftCard active, Bank 2
+
+When the power-on reset circuit asserts the RES signal on Pin 3 of the
+PAL, the SwyftCard is made active in Bank 1. Accessing location
+$COB1 deactivates the SwyftCard for normal Apple IIe operation.
+
+The INH' line is driven by a tri-state driver, so if another card in the
+Apple /Ie asserts the IINH' signal there will not be a bus contention.
+However, there will be a bus contention on the data bus if another card
+attempts to control the bus while the SwyftCard is active.
+
+*/
+
+// CardSwyft represents a Swyft card
+type CardSwyft struct {
+	cardBase
+	bank2 bool
+	rom   []uint8
+}
+
+// NewCardSwyft creates a new CardSwyft
+func NewCardSwyft() *CardSwyft {
+	var c CardSwyft
+	c.name = "SwyftCard"
+
+	// The Cx00 rom is not used. The card is expected to be installed in
+	// slot 3 of an Apple IIe with the 80 column firmware already present.
+	return &c
+}
+
+func (c *CardSwyft) assign(a *Apple2, slot int) {
+	// Load main ROM replacement
+	data, _, err := LoadResource("<internal>/SwyftCard ROM.bin")
+	if err != nil {
+		// The resource should be internal and never fail
+		panic(err)
+	}
+	c.rom = data
+
+	c.addCardSoftSwitchRW(0, func(*ioC0Page) uint8 {
+		a.mmu.inhibitROM(c)
+		c.bank2 = false
+		return 0x55
+	}, "SWYFTONBANK1")
+
+	c.addCardSoftSwitchRW(1, func(*ioC0Page) uint8 {
+		a.mmu.inhibitROM(nil)
+		c.bank2 = false
+		return 0x55
+	}, "SWYFTOFFBANK1")
+
+	c.addCardSoftSwitchRW(2, func(*ioC0Page) uint8 {
+		a.mmu.inhibitROM(c)
+		c.bank2 = true
+		return 0x55
+	}, "SWYFTONBANK2")
+
+	c.cardBase.assign(a, slot)
+	a.mmu.inhibitROM(c)
+}
+
+func (c *CardSwyft) translateAddress(address uint16) uint16 {
+	/*
+		The four 4k sections of the 16k ROM image are mapped:
+			D000-DFFF (page 1)
+			D000-DFFF (page 2)
+			E000-EFFF
+			F000-FFFF
+	*/
+	if address >= 0xE000 {
+		return address - 0xE000 + 0x2000
+	}
+	if !c.bank2 {
+		return address - 0xD000
+	}
+	return address - 0xD000 + 0x1000
+}
+
+func (c *CardSwyft) peek(address uint16) uint8 {
+	return c.rom[c.translateAddress(address)]
+}
+
+func (c *CardSwyft) poke(address uint16, value uint8) {
+	// Nothing
+}
+
+func (c *CardSwyft) setBase(base uint16) {
+	// Nothing
+}

cardSwyft_test.go

@@ -0,0 +1,26 @@
+package izapple2
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestSwyftTutorial(t *testing.T) {
+	at := makeApple2Tester("2e")
+	at.a.AddSwyftCard()
+	err := at.a.AddDisk2(6, "<internal>/SwyftWare_-_SwyftCard_Tutorial.woz", "", nil)
+	if err != nil {
+		panic(err)
+	}
+
+	at.terminateCondition = func(a *Apple2) bool {
+		return a.cpu.GetCycles() > 10_000_000
+	}
+	at.run()
+
+	text := at.getText80()
+	if !strings.Contains(text, "HOW TO USE SWYFTCARD") {
+		t.Errorf("Expected 'HOW TO USE SWYFTCARD', got '%s'", text)
+	}
+
+}

memoryManager.go

@@ -33,15 +33,16 @@ type memoryManager struct {
 	lcAltBank       bool  // Alternate
 
 	// Configuration switches, Apple //e
-	altZeroPage           bool  // Use extra RAM from 0x0000 to 0x01ff. And additional language card block
-	altMainRAMActiveRead  bool  // Use extra RAM from 0x0200 to 0xbfff for read
-	altMainRAMActiveWrite bool  // Use extra RAM from 0x0200 to 0xbfff for write
-	store80Active         bool  // Special pagination for text and graphics areas
-	slotC3ROMActive       bool  // Apple2e slot 3  ROM shadow
-	intCxROMActive        bool  // Apple2e slots internal ROM shadow
-	intC8ROMActive        bool  // C8Rom associated to the internal slot 3. Softswitch not directly accessible. See UtA2e 5-28
-	activeSlot            uint8 // Active slot owner of 0xc800 to 0xcfff
-	extendedRAMBlock      uint8 // Block used for entended memory for RAMWorks cards
+	altZeroPage           bool          // Use extra RAM from 0x0000 to 0x01ff. And additional language card block
+	altMainRAMActiveRead  bool          // Use extra RAM from 0x0200 to 0xbfff for read
+	altMainRAMActiveWrite bool          // Use extra RAM from 0x0200 to 0xbfff for write
+	store80Active         bool          // Special pagination for text and graphics areas
+	slotC3ROMActive       bool          // Apple2e slot 3  ROM shadow
+	intCxROMActive        bool          // Apple2e slots internal ROM shadow
+	intC8ROMActive        bool          // C8Rom associated to the internal slot 3. Softswitch not directly accessible. See UtA2e 5-28
+	activeSlot            uint8         // Active slot owner of 0xc800 to 0xcfff
+	extendedRAMBlock      uint8         // Block used for entended memory for RAMWorks cards
+	mainROMinhibited      memoryHandler // Alternative ROM from 0xd000 to 0xffff provided by a card with the INH signal.
 
 	// Configuration switches, Base64A
 	romPage uint8 // Active ROM page
@@ -151,6 +152,12 @@ func (mmu *memoryManager) getVideoRAM(ext bool) *memoryRange {
 	return mmu.physicalMainRAM
 }
 
+func (mmu *memoryManager) inhibitROM(replacement memoryHandler) {
+	// If a card INH the ROM, it replaces the ROM and the LC RAM
+	mmu.mainROMinhibited = replacement
+	mmu.lastAddressPage = invalidAddressPage // Invalidate cache
+}
+
 func (mmu *memoryManager) accessRead(address uint16) memoryHandler {
 	if address <= addressLimitZero {
 		return mmu.getPhysicalMainRAM(mmu.altZeroPage)
@@ -175,6 +182,9 @@ func (mmu *memoryManager) accessRead(address uint16) memoryHandler {
 	if address <= addressLimitSlotsExtra {
 		return mmu.accessCArea(address)
 	}
+	if mmu.mainROMinhibited != nil {
+		return mmu.mainROMinhibited
+	}
 	if mmu.lcActiveRead {
 		return mmu.accessUpperRAMArea(address)
 	}
@@ -205,6 +215,9 @@ func (mmu *memoryManager) accessWrite(address uint16) memoryHandler {
 	if address <= addressLimitSlotsExtra {
 		return mmu.accessCArea(address)
 	}
+	if mmu.mainROMinhibited != nil {
+		return mmu.mainROMinhibited
+	}
 	if mmu.lcActiveWrite {
 		return mmu.accessUpperRAMArea(address)
 	}