Apple II Memory Expansion Card with up to 1024KB

README.md

@@ -19,7 +19,8 @@ Portable emulator of an Apple II+ or //e. Written in Go.
 - Emulated extension cards:
     - DiskII controller
     - 16Kb Language Card
-    - 256Kb Saturn RAM 
+    - 256Kb Saturn RAM
+    - 1Mb Memory Expansion Card
     - ThunderClock Plus real time clock
     - Bootable hard disk card
     - Apple //e 80 columns with 64Kb extra RAM
@@ -118,8 +119,8 @@ Line:
 - F5: Toggle speed between real and fastest
 - Ctrl-F5: Show current speed in Mhz
 - F6: Toggle between NTSC color TV and green phosphor monochrome monitor
-- F7: Save current state to disk
-- F8: Restore state from disk
+- F7: Save current state to disk (incomplete)
+- F8: Restore state from disk (incomplete)
 - F10: Cycle character generator codepages. Only if the character generator ROM has more than one 2Kb page.
 - F11: Toggle on and off the trace to console of the CPU execution
 - F12: Save a screen snapshot to a file `snapshot.png`
@@ -139,6 +140,8 @@ Only valid on SDL mode
         rom file for the disk drive controller (default "<internal>/DISK2.rom")
   -dumpChars
         shows the character map
+  -fastChipSlot int
+    	slot for the FASTChip accelerator card, -1 for none (default 3)        
   -fastDisk
         set fast mode when the disks are spinning (default true)
   -hd string
@@ -147,6 +150,8 @@ Only valid on SDL mode
         slot for the hard drive if present. -1 for none. (default -1)
   -languageCardSlot int
         slot for the 16kb language card. -1 for none
+  -memoryExpSlot int
+    	  slot for the Memory Expansion card with 1GB. -1 for none (default 4)
   -mhz float
         cpu speed in Mhz, use 0 for full speed. Use F5 to toggle. (default 1.0227142857142857)
   -model string
@@ -162,7 +167,7 @@ Only valid on SDL mode
   -saturnCardSlot int
         slot for the 256kb Saturn card. -1 for none (default -1)
   -thunderClockCardSlot int
-        slot for the ThunderClock Plus card. -1 for none (default 4)
+        slot for the ThunderClock Plus card. -1 for none (default 5)
   -traceCpu
         dump to the console the CPU execution. Use F11 to toggle.
   -traceHD

apple2Setup.go

@@ -154,6 +154,18 @@ func (a *Apple2) AddSaturnCard(slot int) {
 	a.insertCard(&cardSaturn{}, slot)
 }
 
+// AddMemoryExpansionCard inserts an Apple II Memory Expansion card with 1GB
+func (a *Apple2) AddMemoryExpansionCard(slot int, romFile string) error {
+	var c cardMemoryExpansion
+	data, err := loadResource(romFile)
+	if err != nil {
+		return err
+	}
+	c.loadRom(data)
+	a.insertCard(&c, slot)
+	return nil
+}
+
 // AddThunderClockPlusCard inserts a ThunderClock Plus clock card
 func (a *Apple2) AddThunderClockPlusCard(slot int, romFile string) error {
 	var c cardThunderClockPlus

apple2main.go

@@ -61,9 +61,13 @@ func MainApple() *Apple2 {
 		"fastChipSlot",
 		3,
 		"slot for the FASTChip accelerator card, -1 for none")
+	memoryExpansionCardSlot := flag.Int(
+		"memoryExpSlot",
+		4,
+		"slot for the Memory Expansion card with 1GB. -1 for none")
 	thunderClockCardSlot := flag.Int(
 		"thunderClockCardSlot",
-		4,
+		5,
 		"slot for the ThunderClock Plus card. -1 for none")
 	mono := flag.Bool(
 		"mono",
@@ -199,8 +203,16 @@ func MainApple() *Apple2 {
 	if *saturnCardSlot >= 0 {
 		a.AddSaturnCard(*saturnCardSlot)
 	}
+	if *memoryExpansionCardSlot >= 0 {
+		err := a.AddMemoryExpansionCard(*memoryExpansionCardSlot,
+			"<internal>/MemoryExpansionCard-341-0344a.bin")
+		if err != nil {
+			panic(err)
+		}
+	}
 	if *thunderClockCardSlot > 0 {
-		err := a.AddThunderClockPlusCard(*thunderClockCardSlot, "<internal>/ThunderclockPlusROM.bin")
+		err := a.AddThunderClockPlusCard(*thunderClockCardSlot,
+			"<internal>/ThunderclockPlusROM.bin")
 		if err != nil {
 			panic(err)
 		}

cardBase.go

@@ -12,8 +12,9 @@ type card interface {
 
 type cardBase struct {
 	a        *Apple2
-	rom      *memoryRange
-	romExtra *memoryRange
+	romCsxx  *memoryRange
+	romC8xx  *memoryRange
+	romCxxx  *memoryRange
 	slot     int
 	_ssr     [16]softSwitchR
 	_ssw     [16]softSwitchW
@@ -25,25 +26,39 @@ func (c *cardBase) loadRom(data []uint8) {
 	if c.a != nil {
 		panic("Assert failed. Rom must be loaded before inserting the card in the slot")
 	}
-	if len(data) >= 0x100 {
-		c.rom = newMemoryRange(0, data)
-	}
-	if len(data) >= 0x800 {
-		c.romExtra = newMemoryRange(0, data)
+	if len(data) == 0x100 {
+		// Just 256 bytes in Cs00
+		c.romCsxx = newMemoryRange(0, data)
+	} else if len(data) == 0x800 {
+		// The file has C800 to C8FF
+		// The 256 bytes in Cx00 are copied from the first page in C800
+		c.romCsxx = newMemoryRange(0, data)
+		c.romC8xx = newMemoryRange(0xc800, data)
+	} else if len(data) == 0x1000 {
+		// The file covers the full Cxxx range. Only showing the page
+		// corresponding to the slot used.
+		c.romCxxx = newMemoryRange(0xc000, data)
+	} else {
+		panic("Invalid ROM size")
 	}
 }
 
 func (c *cardBase) assign(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.setCardROM(slot, c.rom)
-	}
-
-	if slot != 0 && c.romExtra != nil {
-		c.romExtra.base = uint16(0xc800)
-		a.mmu.setCardROMExtra(slot, c.romExtra)
+	if slot != 0 {
+		if c.romCsxx != nil {
+			// Relocate to the assigned slot
+			c.romCsxx.base = uint16(0xc000 + slot*0x100)
+			a.mmu.setCardROM(slot, c.romCsxx)
+		}
+		if c.romC8xx != nil {
+			a.mmu.setCardROMExtra(slot, c.romC8xx)
+		}
+		if c.romCxxx != nil {
+			a.mmu.setCardROM(slot, c.romCxxx)
+			a.mmu.setCardROMExtra(slot, c.romCxxx)
+		}
 	}
 
 	for i := 0; i < 0x10; i++ {

cardInOut.go

@@ -71,7 +71,7 @@ func (c *cardInOut) assign(a *Apple2, slot int) {
 		}
 	}
 
-	c.rom = newMemoryRange(0xC200, data[0:255])
+	c.romCsxx = newMemoryRange(0xC200, data[0:255])
 
 	if slot != 2 {
 		// To make ifwork on other slots, patch C2, A0 and A1

cardMemoryExpansion.go

@@ -0,0 +1,94 @@
+package apple2
+
+/*
+Apple II Memory Expansion Card
+
+
+See:
+	http://www.apple-iigs.info/doc/fichiers/a2me.pdf
+	http://ae.applearchives.com/files/RamFactor_Manual_1.5.pdf
+	http://www.1000bit.it/support/manuali/apple/technotes/memx/tn.memx.1.html
+
+There is a self test in ROM, address Cs0A.
+
+From the RamFactor docs:
+	The RamFactor card has five addressable registers, which are addressed
+according to the slot number the card is in:
+		$C080+slot * 16low byte of RAM address
+		$C081+slot * 16middle byte of RAM address
+		$C082+slot * 16high byte of RAM address
+		$C083+slot * 16data at addressed location
+		$C08F+slot * 16Firmware Bank Select
+	After power up or Control-Reset, the registers on the card are all in a
+disabled state. They will be enabled by addressing any address in the firmware
+page $Cs00-CsFF.
+	The three address bytes can be both written into and read from. If the card
+has one Megabyte or less, reading the high address byte will always return a
+value in the range $F0-FF. The top nybble can be any value  when you write it,
+but it will always be “F” when you read it. If the card has more than one
+Megabyte of RAM, the top nybble will be a meaningful part of the address.
+
+
+*/
+const (
+	memoryExpansionSize256  = 256 * 1024
+	memoryExpansionSize512  = 512 * 1024
+	memoryExpansionSize768  = 768 * 1024
+	memoryExpansionSize1024 = 1024 * 1024
+	memoryExpansionMask     = 0x000fffff // 10 bits, 1MB
+)
+
+type cardMemoryExpansion struct {
+	ram   [memoryExpansionSize1024]uint8
+	index int
+	cardBase
+}
+
+func (c *cardMemoryExpansion) assign(a *Apple2, slot int) {
+
+	// Read pointer position
+	c.addCardSoftSwitchR(0, func(*ioC0Page) uint8 {
+		return uint8(c.index)
+	}, "MEMORYEXLOR")
+	c.addCardSoftSwitchR(1, func(*ioC0Page) uint8 {
+		return uint8(c.index >> 8)
+	}, "MEMORYEXMIR")
+	c.addCardSoftSwitchR(2, func(*ioC0Page) uint8 {
+		// Top nibble returned is 0xf
+		return uint8(c.index>>16) | 0xf0
+	}, "MEMORYEXHIR")
+
+	// Set pointer position
+	c.addCardSoftSwitchW(0, func(_ *ioC0Page, value uint8) {
+		c.index = (c.index &^ 0xff) + int(value)
+	}, "MEMORYEXLOW")
+	c.addCardSoftSwitchW(1, func(_ *ioC0Page, value uint8) {
+		c.index = (c.index &^ 0xff00) + int(value)<<8
+	}, "MEMORYEXMIW")
+	c.addCardSoftSwitchW(2, func(_ *ioC0Page, value uint8) {
+		// Only lo nibble is used
+		c.index = (c.index &^ 0xff0000) + int(value&0x0f)<<16
+	}, "MEMORYEXHIW")
+
+	// Read data
+	c.addCardSoftSwitchR(3, func(*ioC0Page) uint8 {
+		var value uint8
+		if c.index < len(c.ram) {
+			value = c.ram[c.index]
+		} else {
+			value = 0xde // Ram socket not populated
+		}
+		c.index = (c.index + 1) & memoryExpansionMask
+		return value
+	}, "MEMORYEXR")
+
+	// Write data
+	c.addCardSoftSwitchW(3, func(_ *ioC0Page, value uint8) {
+		if c.index < len(c.ram) {
+			c.ram[c.index] = value
+		}
+		c.index = (c.index + 1) & memoryExpansionMask
+	}, "MEMORYEXW")
+
+	c.cardBase.assign(a, slot)
+}