Partial support for the Basis 108 clone

.gitignore

@@ -7,6 +7,7 @@ frontend/*/*.dsk
 frontend/*/*.po
 frontend/*/*.2mg
 frontend/*/*.hdv
+frontend/*/*.zip
 frontend/a2fyne/a2fyne
 frontend/headless/headless
 frontend/*/snapshot.gif

README.md

@@ -9,6 +9,7 @@ Portable emulator of an Apple II+ or //e. Written in Go.
   - Apple //e with 128Kb of RAM
   - Apple //e enhanced with 128Kb of RAM
   - Base64A clone with 48Kb of base RAM and paged ROM
+  - Basis 108 clone (partial)
 - Storage
   - 16 Sector 5 1/4 diskettes. Uncompressed or compressed witth gzip or zip. Supported formats:
     - NIB (read only)
@@ -228,6 +229,7 @@ The available pre-configured models are:
   2enh: Apple //e
   2plus: Apple ][+
   base64a: Base 64A
+  basis108: Basis 108
   dos32: Apple ][ with 13 sectors disk adapter and DOS 3.2x
   swyft: swyft
 

a2audit_test.go

@@ -22,10 +22,10 @@ func testA2AuditInternal(t *testing.T, model string, removeLangCard bool, cycles
 	if err != nil {
 		t.Fatal(err)
 	}
-	at.terminateCondition = buildTerminateConditionTexts(at, messages, false, cycles)
+	at.terminateCondition = buildTerminateConditionTexts(messages, testTextMode40, cycles)
 	at.run()
 
-	text := at.getText()
+	text := at.getText(testTextMode40)
 	for _, message := range messages {
 		if !strings.Contains(text, message) {
 			t.Errorf("Expected '%s', got '%s'", message, text)

apple2.go

@@ -4,6 +4,7 @@ import (
 	"sync/atomic"
 
 	"github.com/ivanizag/iz6502"
+	"github.com/ivanizag/izapple2/screen"
 )
 
 // Apple2 represents all the components and state of the emulated machine
@@ -12,6 +13,7 @@ type Apple2 struct {
 	cpu     *iz6502.State
 	mmu     *memoryManager
 	io      *ioC0Page
+	video   screen.VideoSource
 	cg      *CharacterGenerator
 	cards   [8]Card
 	tracers []executionTracer
@@ -88,6 +90,10 @@ func (a *Apple2) IsForceCaps() bool {
 	return a.forceCaps
 }
 
+func (a *Apple2) GetCgPageInfo() (int, int) {
+	return a.cg.getPage(), a.cg.getPages()
+}
+
 func (a *Apple2) RequestFastMode() {
 	// Note: if the fastMode is shorter than maxWaitDuration, there won't be any gain.
 	atomic.AddInt32(&a.fastRequestsCounter, 1)
@@ -100,3 +106,7 @@ func (a *Apple2) ReleaseFastMode() {
 func (a *Apple2) registerRemovableMediaDrive(d drive) {
 	a.removableMediaDrives = append(a.removableMediaDrives, d)
 }
+
+func (a *Apple2) GetVideoSource() screen.VideoSource {
+	return a.video
+}

apple2Run.go

@@ -132,7 +132,7 @@ func (a *Apple2) executionTrace() {
 
 func (a *Apple2) dumpDebugInfo() {
 	// See "Apple II Monitors Peeled"
-	pageZeroSymbols := map[int]string{
+	pageZeroSymbols := map[uint16]string{
 		0x36: "CSWL",
 		0x37: "CSWH",
 		0x38: "KSWL",
@@ -145,8 +145,8 @@ func (a *Apple2) dumpDebugInfo() {
 		0xef: "JVAFOLDH",  // Apple Pascal
 	}
 	fmt.Printf("Page zero values:\n")
-	for _, k := range []int{0x36, 0x37, 0x38, 0x39, 0xe2, 0xe3, 0xec, 0xed, 0xee, 0xef} {
+	for _, k := range []uint16{0x36, 0x37, 0x38, 0x39, 0xe2, 0xe3, 0xec, 0xed, 0xee, 0xef} {
-		d := a.mmu.physicalMainRAM.data[k]
+		d := a.mmu.physicalMainRAM.peek(k)
 		fmt.Printf("  %v(0x%x): 0x%02x\n", pageZeroSymbols[k], k, d)
 	}
 

apple2Tester.go

@@ -48,12 +48,22 @@ func (at *apple2Tester) run() {
 	at.a.Run()
 }
 
-func (at *apple2Tester) getText() string {
+type testTextModeFunc func(a *Apple2) string
-	return screen.RenderTextModeString(at.a, false, false, false, at.a.isApple2e)
+
+var testTextMode40 testTextModeFunc = func(a *Apple2) string {
+	return screen.RenderTextModeString(a.video, false, false, false, a.hasLowerCase, false)
 }
 
-func (at *apple2Tester) getText80() string {
+var testTextMode80 testTextModeFunc = func(a *Apple2) string {
-	return screen.RenderTextModeString(at.a, true, false, false, at.a.isApple2e)
+	return screen.RenderTextModeString(a.video, true, false, false, a.hasLowerCase, false)
+}
+
+var testTextMode80AltOrder testTextModeFunc = func(a *Apple2) string {
+	return screen.RenderTextModeString(a.video, true, false, false, a.hasLowerCase, true)
+}
+
+func (at *apple2Tester) getText(textMode testTextModeFunc) string {
+	return textMode(at.a)
 }
 
 /*
@@ -66,12 +76,12 @@ func (at *apple2Tester) getText80() string {
 
 const textCheckInterval = uint64(100_000)
 
-func buildTerminateConditionText(at *apple2Tester, needle string, col80 bool, timeoutCycles uint64) terminateConditionFunc {
+func buildTerminateConditionText(needle string, textMode testTextModeFunc, timeoutCycles uint64) terminateConditionFunc {
 	needles := []string{needle}
-	return buildTerminateConditionTexts(at, needles, col80, timeoutCycles)
+	return buildTerminateConditionTexts(needles, textMode, timeoutCycles)
 }
 
-func buildTerminateConditionTexts(at *apple2Tester, needles []string, col80 bool, timeoutCycles uint64) terminateConditionFunc {
+func buildTerminateConditionTexts(needles []string, textMode testTextModeFunc, timeoutCycles uint64) terminateConditionFunc {
 	lastCheck := uint64(0)
 	found := false
 	return func(a *Apple2) bool {
@@ -81,12 +91,7 @@ func buildTerminateConditionTexts(at *apple2Tester, needles []string, col80 bool
 		}
 		if cycles-lastCheck > textCheckInterval {
 			lastCheck = cycles
-			var text string
+			text := textMode(a)
-			if col80 {
-				text = at.getText80()
-			} else {
-				text = at.getText()
-			}
 			for _, needle := range needles {
 				if !strings.Contains(text, needle) {
 					return false

base64a.go

@@ -1,7 +1,5 @@
 package izapple2
 
-import "fmt"
-
 /*
 	Copam BASE64A adaptation.
 */
@@ -16,35 +14,14 @@ const (
 )
 
 func loadBase64aRom(a *Apple2) error {
-	// Load the 6 PROM dumps
+	return loadMultiPageRom(a, []string{
-	romBanksBytes := make([][]uint8, base64aRomBankCount)
+		"<internal>/BASE64A_D0.BIN",
-	for j := range romBanksBytes {
+		"<internal>/BASE64A_D8.BIN",
-		romBanksBytes[j] = make([]uint8, 0, base64aRomBankSize)
+		"<internal>/BASE64A_E0.BIN",
-	}
+		"<internal>/BASE64A_E8.BIN",
-
+		"<internal>/BASE64A_F0.BIN",
-	for i := 0; i < base64aRomChipCount; i++ {
+		"<internal>/BASE64A_F8.BIN",
-		filename := fmt.Sprintf("<internal>/BASE64A_%X.BIN", 0xd0+i*0x08)
+	})
-		data, _, err := LoadResource(filename)
-		if err != nil {
-			return err
-		}
-		for j := range romBanksBytes {
-			start := (j * base64aRomWindowSize) % len(data)
-			romBanksBytes[j] = append(romBanksBytes[j], data[start:start+base64aRomWindowSize]...)
-		}
-	}
-
-	// Create paged ROM
-	romData := make([]uint8, 0, base64aRomBankSize*base64aRomBankCount)
-	for _, bank := range romBanksBytes {
-		romData = append(romData, bank...)
-	}
-	rom := newMemoryRangePagedROM(0xd000, romData, "Base64 ROM", base64aRomBankCount)
-
-	// Start with first bank active
-	rom.setPage(0)
-	a.mmu.physicalROM = rom
-	return nil
 }
 
 func addBase64aSoftSwitches(io *ioC0Page) {

boardBasis108.go

@@ -0,0 +1,126 @@
+package izapple2
+
+import "github.com/ivanizag/izapple2/screen"
+
+/*
+	Basis 108 clone
+
+	Manual: https://www.applefritter.com/files/Basis%201982%20basis%20108%20instruction%20manual.pdf
+
+	ROM: Two pages of 12 KB each. Page 0 sets the 80 column mode. Page 1 starts in 40 column mode.
+
+	Character ROM: Four pages, the inverse and flash characters are built from the normal ones. Pages:
+		0: Apple II characters (no lowercase)
+		1: German ASCII
+		2: ASCII (default)
+		3: APL symbols
+
+	Memory: Has a full 64KB extra RAM replacing both main and LC RAM. It can be mapped on 8kb blocks with
+	new softswitches.
+
+	Video: 80 columns are made by having a sideways static RAM.
+
+	The keyboard can generate interrupts.
+
+	Missing: second 64kb block, keyboard interrupts, Z80 emulation, Parallel an Serial.
+*/
+
+func loadBasis108Rom(a *Apple2) error {
+	return loadMultiPageRom(a, []string{
+		"<internal>/Basis108_D83_D0.BIN",
+		"<internal>/Basis108_D70_D8.BIN",
+		"<internal>/Basis108_D56_E0.BIN",
+		"<internal>/Basis108_D40_E8.BIN",
+		"<internal>/Basis108_D39_F0.BIN",
+		"<internal>/Basis108_D25_F8.BIN",
+	})
+}
+
+type videoBasis108 struct {
+	video
+	ram   *memoryRangeBasis108
+	col80 bool
+}
+
+func newVideoBasis108(a *Apple2, ram *memoryRangeBasis108) *videoBasis108 {
+	var v videoBasis108
+	v.video = *newVideo(a)
+	v.ram = ram
+	return &v
+}
+
+// GetCurrentVideoMode returns the active video mode
+func (v *videoBasis108) GetCurrentVideoMode() uint32 {
+	if v.col80 {
+		mode := screen.VideoText80AltOrder
+
+		isTextMode := v.a.io.isSoftSwitchActive(ioFlagText)
+		isHiResMode := v.a.io.isSoftSwitchActive(ioFlagHiRes)
+		if isTextMode {
+			mode |= screen.VideoText80
+		} else if isHiResMode {
+			mode |= screen.VideoHGR
+		} else {
+			mode |= screen.VideoDGR
+		}
+
+		isSecondPage := v.a.io.isSoftSwitchActive(ioFlagSecondPage)
+		if isSecondPage {
+			mode |= screen.VideoSecondPage
+		}
+
+		return mode
+	}
+
+	return v.video.GetCurrentVideoMode()
+}
+
+// GetTextMemory returns a slice to the text memory pages
+func (v *videoBasis108) GetTextMemory(secondPage bool, ext bool) []uint8 {
+	return v.ram.getTextMemory(secondPage, ext)
+}
+
+func addBasis108SoftSwitches(io *ioC0Page, ram *memoryRangeBasis108, video *videoBasis108, cg *CharacterGenerator) {
+
+	// Character generator softswitches
+	io.addSoftSwitchW(0x00, buildNotImplementedSoftSwitchW(io), "BASIS108-CG-SW0-OFF") // Inverse?
+	io.addSoftSwitchW(0x01, buildNotImplementedSoftSwitchW(io), "BASIS108-CG-SW0-ON")  // Flash?
+	io.addSoftSwitchW(0x02, func(_ uint8) { cg.setPage(cg.page & 0x02) }, "BASIS108-CG-SW2-OFF")
+	io.addSoftSwitchW(0x03, func(_ uint8) { cg.setPage(cg.page | 0x01) }, "BASIS108-CG-SW2-ON")
+	io.addSoftSwitchW(0x04, func(_ uint8) { cg.setPage(cg.page & 0x01) }, "BASIS108-CG-SW1-OFF")
+	io.addSoftSwitchW(0x05, func(_ uint8) { cg.setPage(cg.page | 0x02) }, "BASIS108-CG-SW1-ON")
+	io.addSoftSwitchW(0x06, buildNotImplementedSoftSwitchW(io), "BASIS108-CG-SW0-OFF")
+	io.addSoftSwitchW(0x07, buildNotImplementedSoftSwitchW(io), "BASIS108-CG-SW0-ON")
+
+	// Keyboard interrupts
+	io.addSoftSwitchW(0x08, buildNotImplementedSoftSwitchW(io), "BASIS108-KBDINT-OFF")
+	io.addSoftSwitchW(0x09, buildNotImplementedSoftSwitchW(io), "BASIS108-KBDINT-ON")
+
+	// 80 column softswitches
+	io.addSoftSwitchW(0x0A, func(_ uint8) { video.col80 = false }, "BASIS108-80COL-OFF")
+	io.addSoftSwitchW(0x0B, func(_ uint8) { video.col80 = true }, "BASIS108-80COL-ON")
+	io.addSoftSwitchW(0x0C, func(_ uint8) { ram.staticRam = false }, "BASIS108-STATICRAM-OFF")
+	io.addSoftSwitchW(0x0D, func(_ uint8) { ram.staticRam = true }, "BASIS108-STATICRAM-ON")
+
+	// Language card configuration
+	io.addSoftSwitchW(0x0E, buildNotImplementedSoftSwitchW(io), "BASIS108-LANG-ON")
+	io.addSoftSwitchW(0x0F, buildNotImplementedSoftSwitchW(io), "BASIS108-LANG-OFF")
+
+	// RAM bank softswitches
+	io.addSoftSwitchW(0x60, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM0000-BANK0")
+	io.addSoftSwitchW(0x61, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM0000-BANK1")
+	io.addSoftSwitchW(0x62, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM2000-BANK0")
+	io.addSoftSwitchW(0x63, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM2000-BANK1")
+	io.addSoftSwitchW(0x64, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM4000-BANK0")
+	io.addSoftSwitchW(0x65, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM4000-BANK1")
+	io.addSoftSwitchW(0x66, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM6000-BANK0")
+	io.addSoftSwitchW(0x67, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM6000-BANK1")
+	io.addSoftSwitchW(0x68, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM8000-BANK0")
+	io.addSoftSwitchW(0x69, buildNotImplementedSoftSwitchW(io), "BASIS108-RAM8000-BANK1")
+	io.addSoftSwitchW(0x6A, buildNotImplementedSoftSwitchW(io), "BASIS108-RAMA000-BANK0")
+	io.addSoftSwitchW(0x6B, buildNotImplementedSoftSwitchW(io), "BASIS108-RAMA000-BANK1")
+	io.addSoftSwitchW(0x6C, buildNotImplementedSoftSwitchW(io), "BASIS108-RAMD000-BANK0")
+	io.addSoftSwitchW(0x6D, buildNotImplementedSoftSwitchW(io), "BASIS108-RAMD000-BANK1")
+	io.addSoftSwitchW(0x6E, buildNotImplementedSoftSwitchW(io), "BASIS108-RAME000-BANK0")
+	io.addSoftSwitchW(0x6F, buildNotImplementedSoftSwitchW(io), "BASIS108-RAME000-BANK1")
+}

cardBrainBoard_test.go

@@ -29,9 +29,9 @@ func TestBrainBoardCardWozaniam(t *testing.T) {
 	}
 	at.run()
 
-	at.terminateCondition = buildTerminateConditionText(at, "_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@", false, 100_000)
+	at.terminateCondition = buildTerminateConditionText("_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@", testTextMode40, 100_000)
 
-	text := at.getText()
+	text := at.getText(testTextMode40)
 	if !strings.Contains(text, "_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@_@") {
 		t.Errorf("Expected screen filled with _@_@', got '%s'", text)
 	}
@@ -40,10 +40,10 @@ func TestBrainBoardCardWozaniam(t *testing.T) {
 func TestBrainBoardCardIntegerBasic(t *testing.T) {
 	at := buildBrainBoardTester(t, "brainboard,switch=down")
 
-	at.terminateCondition = buildTerminateConditionText(at, "APPLE ][\n>", false, 1_000_000)
+	at.terminateCondition = buildTerminateConditionText("APPLE ][\n>", testTextMode40, 1_000_000)
 	at.run()
 
-	text := at.getText()
+	text := at.getText(testTextMode40)
 	if !strings.Contains(text, "APPLE ][\n>") {
 		t.Errorf("Expected APPLE ][' and '>', got '%s'", text)
 	}

cardCat_test.go

@@ -19,10 +19,10 @@ func testCardDetectedInternal(t *testing.T, model string, card string, cycles ui
 	if err != nil {
 		t.Fatal(err)
 	}
-	at.terminateCondition = buildTerminateConditionText(at, banner, true, cycles)
+	at.terminateCondition = buildTerminateConditionText(banner, testTextMode80, cycles)
 	at.run()
 
-	text := at.getText80()
+	text := at.getText(testTextMode80)
 	if !strings.Contains(text, banner) {
 		t.Errorf("Expected '%s', got '%s'", banner, text)
 	}

cardDan2Controller.go

@@ -195,7 +195,7 @@ func (s *cardDan2ControllerSlot) openFile() (*os.File, error) {
 	return nil, err
 }
 
-func (s *cardDan2ControllerSlot) status(unit uint8) error {
+func (s *cardDan2ControllerSlot) status(_ uint8) error {
 	file, err := s.openFile()
 	if err != nil {
 		return err

cardDan2Controller_test.go

@@ -14,11 +14,11 @@ func TestDan2Controller(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	at.terminateCondition = buildTerminateConditionText(at, "NEW VOL", true, 10_000_000)
+	at.terminateCondition = buildTerminateConditionText("NEW VOL", testTextMode40, 10_000_000)
 
 	at.run()
 
-	text := at.getText()
+	text := at.getText(testTextMode40)
 	if !strings.Contains(text, "NEW VOL") {
 		t.Errorf("Expected Bitsy Bye screen, got '%s'", text)
 	}

cardProDOSRomCard3.go

@@ -52,10 +52,11 @@ func newCardProDOSRomCard3Builder() *cardBuilder {
 	}
 }
 
+//lint:ignore U1000 this is used to write debug code
 func newCardProDOSNVRAMDriveBuilder() *cardBuilder {
 	return &cardBuilder{
 		name:        "ProDOS 4MB NVRAM DRive",
-		description: "A bootable 4 MB NVRAM card by Ralle Palaveev",
+		description: "A bootable 4 MB NVRAM card by Ralle Palaveev, WIP",
 		defaultParams: &[]paramSpec{
 			{"image", "ROM image with the ProDOS volume", ""},
 		},

cardSwyft_test.go

@@ -11,11 +11,11 @@ func TestSwyftTutorial(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	at.terminateCondition = buildTerminateConditionText(at, "HOW TO USE SWYFTCARD", true, 10_000_000)
+	at.terminateCondition = buildTerminateConditionText("HOW TO USE SWYFTCARD", testTextMode80, 10_000_000)
 
 	at.run()
 
-	text := at.getText80()
+	text := at.getText(testTextMode80)
 	if !strings.Contains(text, "HOW TO USE SWYFTCARD") {
 		t.Errorf("Expected 'HOW TO USE SWYFTCARD', got '%s'", text)
 	}

characterGenerator.go

@@ -29,8 +29,9 @@ func charGenColumnsMap2e(column int) int {
 }
 
 const (
-	charGenPageSize2Plus = 2048
+	charGenPageSize2Plus    = 2048
-	charGenPageSize2E    = 2048 * 2
+	charGenPageSize2E       = 2048 * 2
+	charGenPageSizeBasis108 = 1024
 )
 
 // NewCharacterGenerator instantiates a new Character Generator with the rom on the file given
@@ -59,9 +60,13 @@ func (cg *CharacterGenerator) load(filename string) error {
 	return nil
 }
 
+func (cg *CharacterGenerator) getPages() int {
+	return len(cg.data) / cg.pageSize
+}
+
 func (cg *CharacterGenerator) setPage(page int) {
 	// Some clones had a switch to change codepage with extra characters
-	pages := len(cg.data) / cg.pageSize
+	pages := cg.getPages()
 	cg.page = page % pages
 }
 
@@ -74,7 +79,8 @@ func (cg *CharacterGenerator) nextPage() {
 }
 
 func (cg *CharacterGenerator) getPixel(char uint8, row int, column int) bool {
-	bits := cg.data[int(char)*8+row+cg.page*cg.pageSize]
+	rowPos := (int(char)*8 + row) % cg.pageSize
+	bits := cg.data[rowPos+cg.page*cg.pageSize]
 	bit := cg.columnMap(column)
 	value := bits >> uint(bit) & 1
 	return value == 1
@@ -87,6 +93,10 @@ func setupCharactedGenerator(a *Apple2, board string, charRomFile string) error
 	switch board {
 	case "2plus":
 		charGenMap = charGenColumnsMap2Plus
+	case "basis108":
+		charGenMap = charGenColumnsMap2Plus
+		pageSize = charGenPageSizeBasis108
+		initialCharGenPage = 2
 	case "2e":
 		charGenMap = charGenColumnsMap2e
 		pageSize = charGenPageSize2E
@@ -94,7 +104,7 @@ func setupCharactedGenerator(a *Apple2, board string, charRomFile string) error
 		charGenMap = charGenColumnsMapBase64a
 		initialCharGenPage = 1
 	default:
-		return fmt.Errorf("board %s not supported it must be '2plus', '2e' or 'base64a'", board)
+		return fmt.Errorf("board %s not supported it must be '2plus', '2e', 'base64a', 'basis108", board)
 	}
 
 	cg, err := newCharacterGenerator(charRomFile, charGenMap, pageSize)

configs/basis108.cfg

@@ -0,0 +1,8 @@
+name: Basis 108
+parent: _base
+board: basis108
+rom: <custom>
+charrom: <internal>/D29_basis_cg_2532.rom.BIN
+s0: language
+s3: videx
+s6: diskii,disk1=<internal>/dos33.dsk

doc/usage.txt

@@ -50,6 +50,7 @@ The available pre-configured models are:
   2enh: Apple //e
   2plus: Apple ][+
   base64a: Base 64A
+  basis108: Basis 108
   dos32: Apple ][ with 13 sectors disk adapter and DOS 3.2x
   swyft: swyft
 

e2e_boot_test.go

@@ -5,7 +5,7 @@ import (
 	"testing"
 )
 
-func testBoots(t *testing.T, model string, disk string, overrides *configuration, cycles uint64, banner string, prompt string, col80 bool) {
+func testBoots(t *testing.T, model string, disk string, overrides *configuration, cycles uint64, banner string, prompt string, textMode testTextModeFunc) {
 	if overrides == nil {
 		overrides = newConfiguration()
 	}
@@ -23,15 +23,10 @@ func testBoots(t *testing.T, model string, disk string, overrides *configuration
 	if err != nil {
 		t.Fatal(err)
 	}
-	at.terminateCondition = buildTerminateConditionTexts(at, []string{banner, prompt}, col80, cycles)
+	at.terminateCondition = buildTerminateConditionTexts([]string{banner, prompt}, textMode, cycles)
 	at.run()
 
-	var text string
+	text := at.getText(textMode)
-	if col80 {
-		text = at.getText80()
-	} else {
-		text = at.getText()
-	}
 	if !strings.Contains(text, banner) {
 		t.Errorf("Expected '%s', got '%s'", banner, text)
 	}
@@ -42,36 +37,40 @@ func testBoots(t *testing.T, model string, disk string, overrides *configuration
 }
 
 func TestPlusBoots(t *testing.T) {
-	testBoots(t, "2plus", "", nil, 200_000, "APPLE ][", "\n]", false)
+	testBoots(t, "2plus", "", nil, 200_000, "APPLE ][", "\n]", testTextMode40)
 }
 
 func Test2EBoots(t *testing.T) {
-	testBoots(t, "2e", "", nil, 200_000, "Apple ][", "\n]", false)
+	testBoots(t, "2e", "", nil, 200_000, "Apple ][", "\n]", testTextMode40)
 }
 
 func Test2EnhancedBoots(t *testing.T) {
-	testBoots(t, "2enh", "", nil, 200_000, "Apple //e", "\n]", false)
+	testBoots(t, "2enh", "", nil, 200_000, "Apple //e", "\n]", testTextMode40)
 }
 
 func TestBase64Boots(t *testing.T) {
-	testBoots(t, "base64a", "", nil, 1_000_000, "BASE 64A", "\n]", false)
+	testBoots(t, "base64a", "", nil, 1_000_000, "BASE 64A", "\n]", testTextMode40)
+}
+
+func TestBasis108Boots(t *testing.T) {
+	testBoots(t, "basis108", "", nil, 1_000_000, "B a s i s   1 0 8", "\n]", testTextMode80AltOrder)
 }
 
 func TestPlusDOS32Boots(t *testing.T) {
 	overrides := newConfiguration()
 	overrides.set(confS0, "multirom,bank=7,basic=0")
 	overrides.set(confS6, "diskii,sectors13,disk1=<internal>/dos32.nib")
-	testBoots(t, "2plus", "", overrides, 100_000_000, "MASTER DISKETTE VERSION 3.2 STANDARD", "\n>", false)
+	testBoots(t, "2plus", "", overrides, 100_000_000, "MASTER DISKETTE VERSION 3.2 STANDARD", "\n>", testTextMode40)
 }
 
 func TestPlusDOS33Boots(t *testing.T) {
-	testBoots(t, "2plus", "<internal>/dos33.dsk", nil, 100_000_000, "DOS VERSION 3.3", "\n]", false)
+	testBoots(t, "2plus", "<internal>/dos33.dsk", nil, 100_000_000, "DOS VERSION 3.3", "\n]", testTextMode40)
 }
 
 func TestProdDOSBoots(t *testing.T) {
-	testBoots(t, "2enh", "<internal>/ProDOS_2_4_3.po", nil, 100_000_000, "BITSY  BYE", "NEW VOL", false)
+	testBoots(t, "2enh", "<internal>/ProDOS_2_4_3.po", nil, 100_000_000, "BITSY  BYE", "NEW VOL", testTextMode40)
 }
 
 func TestCPM65Boots(t *testing.T) {
-	testBoots(t, "2enh", "<internal>/cpm65.po", nil, 5_000_000, "CP/M-65 for the Apple II", "\nA>", true)
+	testBoots(t, "2enh", "<internal>/cpm65.po", nil, 5_000_000, "CP/M-65 for the Apple II", "\nA>", testTextMode80)
 }

frontend/a2fyne/fyneKeyboard.go

@@ -51,7 +51,7 @@ func (k *keyboard) putKeyAction(keyEvent *fyne.KeyEvent, press bool) {
 		case fyne.KeyF1:
 			k.s.a.SendCommand(izapple2.CommandReset)
 		case fyne.KeyF12:
-			screen.AddScenario(k.s.a, "../../screen/test_resources/")
+			screen.AddScenario(k.s.a.GetVideoSource(), "../../screen/test_resources/")
 		}
 	}
 
@@ -128,7 +128,7 @@ func (k *keyboard) putKey(keyEvent *fyne.KeyEvent) {
 		k.s.a.SendCommand(izapple2.CommandToggleCPUTrace)
 	case fyne.KeyF12:
 		//case fyne.KeyPrintScreen:
-		err := screen.SaveSnapshot(k.s.a, k.s.screenMode, "snapshot.png")
+		err := screen.SaveSnapshot(k.s.a.GetVideoSource(), k.s.screenMode, "snapshot.png")
 		if err != nil {
 			fmt.Printf("Error saving snapshoot: %v.\n.", err)
 		} else {

frontend/a2fyne/main.go

@@ -95,11 +95,12 @@ func fyneRun(s *state) {
 			case <-ticker.C:
 				if !s.a.IsPaused() {
 					var img *image.RGBA
+					vs := s.a.GetVideoSource()
 					if s.showPages {
-						img = screen.SnapshotParts(s.a, s.screenMode)
+						img = screen.SnapshotParts(vs, s.screenMode)
-						s.win.SetTitle(fmt.Sprintf("%v %v %vx%v", s.a.Name, screen.VideoModeName(s.a), img.Rect.Dx()/2, img.Rect.Dy()/2))
+						s.win.SetTitle(fmt.Sprintf("%v %v %vx%v", s.a.Name, screen.VideoModeName(vs), img.Rect.Dx()/2, img.Rect.Dy()/2))
 					} else {
-						img = screen.Snapshot(s.a, s.screenMode)
+						img = screen.Snapshot(vs, s.screenMode)
 					}
 					display.Image = img
 					canvas.Refresh(display)

frontend/a2fyne/toolbar.go

@@ -35,7 +35,7 @@ func buildToolbar(s *state) *widget.Toolbar {
 		}))
 	tb.Append(widget.NewToolbarAction(
 		theme.NewThemedResource(resourceCameraSvg), func() {
-			err := screen.SaveSnapshot(s.a, s.screenMode, "snapshot.png")
+			err := screen.SaveSnapshot(s.a.GetVideoSource(), s.screenMode, "snapshot.png")
 			if err != nil {
 				s.app.SendNotification(fyne.NewNotification(
 					s.win.Title(),

frontend/a2sdl/main.go

@@ -107,16 +107,18 @@ func sdlRun(a *izapple2.Apple2) {
 
 		if !a.IsPaused() {
 			var img *image.RGBA
+			vs := a.GetVideoSource()
 			if kp.showHelp {
-				img = screen.SnapshotMessageGenerator(a, helpMessage)
+				img = screen.SnapshotMessageGenerator(vs, helpMessage)
 			} else if kp.showCharGen {
-				img = screen.SnapshotCharacterGenerator(a, kp.showAltText)
+				cgPage, cgPages := a.GetCgPageInfo()
-				window.SetTitle(fmt.Sprintf("%v character map", a.Name))
+				img = screen.SnapshotCharacterGenerator(vs, kp.showAltText)
+				window.SetTitle(fmt.Sprintf("%v character map, page %v/%v", a.Name, cgPage+1, cgPages))
 			} else if kp.showPages {
-				img = screen.SnapshotParts(a, kp.screenMode)
+				img = screen.SnapshotParts(vs, kp.screenMode)
-				window.SetTitle(fmt.Sprintf("%v %v %vx%v", a.Name, screen.VideoModeName(a), img.Rect.Dx()/2, img.Rect.Dy()/2))
+				window.SetTitle(fmt.Sprintf("%v %v %vx%v", a.Name, screen.VideoModeName(vs), img.Rect.Dx()/2, img.Rect.Dy()/2))
 			} else {
-				img = screen.Snapshot(a, kp.screenMode)
+				img = screen.Snapshot(vs, kp.screenMode)
 			}
 			if img != nil {
 				surface, err := sdl.CreateRGBSurfaceFrom(unsafe.Pointer(&img.Pix[0]),

frontend/a2sdl/sdlKeyboard.go

@@ -129,9 +129,9 @@ func (k *sdlKeyboard) putKey(keyEvent *sdl.KeyboardEvent) {
 		fallthrough
 	case sdl.K_PRINTSCREEN:
 		if ctrl {
-			screen.AddScenario(k.a, "../../screen/test_resources/")
+			screen.AddScenario(k.a.GetVideoSource(), "../../screen/test_resources/")
 		} else {
-			err := screen.SaveSnapshot(k.a, screen.ScreenModeNTSC, "snapshot.png")
+			err := screen.SaveSnapshot(k.a.GetVideoSource(), screen.ScreenModeNTSC, "snapshot.png")
 			if err != nil {
 				fmt.Printf("Error saving snapshoot: %v.\n.", err)
 			} else {

frontend/headless/main.go

@@ -97,7 +97,7 @@ func main() {
 
 		// Old:
 		case "png":
-			err := screen.SaveSnapshot(a, screen.ScreenModeNTSC, "snapshot.png")
+			err := screen.SaveSnapshot(a.GetVideoSource(), screen.ScreenModeNTSC, "snapshot.png")
 			if err != nil {
 				fmt.Printf("Error saving screen: %v.\n.", err)
 			} else {
@@ -105,7 +105,7 @@ func main() {
 			}
 
 		case "pngm":
-			err := screen.SaveSnapshot(a, screen.ScreenModePlain, "snapshot.png")
+			err := screen.SaveSnapshot(a.GetVideoSource(), screen.ScreenModePlain, "snapshot.png")
 			if err != nil {
 				fmt.Printf("Error saving screen: %v.\n.", err)
 			} else {
@@ -187,14 +187,14 @@ func SaveGif(a *izapple2.Apple2, filename string) error {
 
 	planned := time.Now()
 	for i := 0; i < frames; i++ {
-		lapse := planned.Sub(time.Now())
+		lapse := time.Until(planned)
 		fmt.Printf("%v\n", lapse)
 		if lapse > 0 {
 			time.Sleep(lapse)
 		}
 
 		fmt.Printf("%v\n", time.Now())
-		img := screen.SnapshotPaletted(a, screen.ScreenModeNTSC)
+		img := screen.SnapshotPaletted(a.GetVideoSource(), screen.ScreenModeNTSC)
 		animation.Image = append(animation.Image, img)
 		animation.Delay = append(animation.Delay, delayHundredsS)
 

memoryManager.go

@@ -9,7 +9,7 @@ type memoryManager struct {
 	apple2 *Apple2
 
 	// Main RAM area: 0x0000 to 0xbfff
-	physicalMainRAM *memoryRange // 0x0000 to 0xbfff, Up to 48 Kb
+	physicalMainRAM memoryRangeHandler // 0x0000 to 0xbfff, Up to 48 Kb
 
 	// Slots area: 0xc000 to 0xcfff
 	cardsROM      [8]memoryHandler //0xcs00 to 0xcSff. 256 bytes for each card
@@ -70,13 +70,15 @@ type memoryHandler interface {
 	poke(uint16, uint8)
 }
 
+type memoryRangeHandler interface {
+	memoryHandler
+	subRange(a, b uint16) []uint8
+}
+
 func newMemoryManager(a *Apple2) *memoryManager {
 	var mmu memoryManager
 	mmu.apple2 = a
-	mmu.physicalMainRAM = newMemoryRange(0, make([]uint8, 0xc000), "Main RAM")
-
 	mmu.slotC3ROMActive = true // For II+, this is the default behaviour
-
 	return &mmu
 }
 
@@ -147,7 +149,7 @@ func (mmu *memoryManager) getPhysicalMainRAM(ext bool) memoryHandler {
 	return mmu.physicalMainRAM
 }
 
-func (mmu *memoryManager) getVideoRAM(ext bool) *memoryRange {
+func (mmu *memoryManager) getVideoRAM(ext bool) memoryRangeHandler {
 	if ext && mmu.hasExtendedRAM() {
 		// The video memory uses the first extended RAM block, even with RAMWorks
 		return mmu.physicalExtRAM[0]
@@ -236,7 +238,7 @@ func (mmu *memoryManager) peekWord(address uint16) uint16 {
 func (mmu *memoryManager) Peek(address uint16) uint8 {
 	mh := mmu.accessRead(address)
 	if mh == nil {
-		return 0xf4 // Or some random number
+		return uint8(address) // Or some random number
 	}
 	value := mh.peek(address)
 	//if address >= 0xc400 && address < 0xc500 {
@@ -310,6 +312,15 @@ func (mmu *memoryManager) initLanguageRAM(groups uint8) {
 	}
 }
 
+func (mmu *memoryManager) initMainRAM() {
+	// Apple II+ main RAM
+	mmu.physicalMainRAM = newMemoryRange(0, make([]uint8, 0xc000), "Main RAM")
+}
+
+func (mmu *memoryManager) initCustomRAM(customRam memoryRangeHandler) {
+	mmu.physicalMainRAM = customRam
+}
+
 func (mmu *memoryManager) initExtendedRAM(groups int) {
 	// Apple IIe 80 col card with 64Kb style RAM or RAMWorks (up to 256 banks)
 	mmu.physicalExtRAM = make([]*memoryRange, groups)

memoryRange.go

@@ -66,7 +66,12 @@ func (m *memoryRangeROM) getPage() uint8 {
 }
 
 func (m *memoryRangeROM) peek(address uint16) uint8 {
-	return m.data[address-m.base+m.pageOffset]
+	pos := address - m.base + m.pageOffset
+	if pos >= uint16(len(m.data)) {
+		return uint8(address) // Non existent memory
+	}
+
+	return m.data[pos]
 }
 func (m *memoryRangeROM) poke(address uint16, value uint8) {
 	// Ignore
@@ -81,7 +86,7 @@ func identifyMemory(m memoryHandler) string {
 
 	rom, ok := m.(*memoryRangeROM)
 	if ok {
-		return fmt.Sprintf("ROM 0x%04x %s", rom.base, ram.name)
+		return fmt.Sprintf("ROM 0x%04x %s", rom.base, rom.name)
 	}
 
 	return ("Unknown memory")

memoryRangeBasis108.go

@@ -0,0 +1,73 @@
+package izapple2
+
+/*
+	The Basis 108 clone has 128kb of RAM plus 2KB of static RAM at $0400 for 80 columns text.
+*/
+
+type memoryRangeBasis108 struct {
+	dataMain   []uint8
+	dataAux    []uint8
+	dataStatic []uint8
+	name       string
+
+	staticRam bool
+	auxRam    bool
+}
+
+func newMemoryRangeBasis108() *memoryRangeBasis108 {
+	var m memoryRangeBasis108
+	m.dataMain = make([]uint8, 48*1024)
+	m.dataAux = make([]uint8, 48*1024)
+	m.dataStatic = make([]uint8, 0xc000-0x0400)
+
+	// How is the static RAM initialized?
+	for i := 0; i < len(m.dataStatic); i++ {
+		m.dataStatic[i] = ' ' + 0x80
+	}
+
+	m.name = "Basis 108 RAM"
+	return &m
+}
+
+func (m *memoryRangeBasis108) peek(address uint16) uint8 {
+	if m.staticRam && address >= 0x0400 && address < 0x0c00 {
+		return m.dataStatic[address-0x0400]
+	}
+
+	if m.auxRam {
+		return m.dataAux[address]
+	}
+	return m.dataMain[address]
+}
+
+func (m *memoryRangeBasis108) poke(address uint16, value uint8) {
+	if m.staticRam && address >= 0x0400 && address < 0x0c00 {
+		m.dataStatic[address-0x0400] = value
+	} else if m.auxRam {
+		m.dataAux[address] = value
+	} else {
+		m.dataMain[address] = value
+	}
+}
+
+func (m *memoryRangeBasis108) subRange(a, b uint16) []uint8 {
+	if m.staticRam && a >= 0x0400 && b < 0x0c00 {
+		return m.dataStatic[a-0x0400 : b-0x0400]
+	}
+	if m.auxRam {
+		return m.dataAux[a:b]
+	}
+	return m.dataMain[a:b]
+}
+
+func (m *memoryRangeBasis108) getTextMemory(secondPage bool, ext bool) []uint8 {
+	addressStart := textPage1Address
+	if secondPage {
+		addressStart = textPage2Address
+	}
+
+	if ext {
+		return m.dataStatic[addressStart-0x0400 : addressStart-0x0400+textPageSize]
+	}
+	return m.dataMain[addressStart : addressStart+textPageSize]
+}

screen/loRes.go

@@ -44,7 +44,7 @@ func snapshotLoRes(vs VideoSource, isSecondPage bool, light color.Color) *image.
 }
 
 func snapshotMeRes(vs VideoSource, isSecondPage bool, light color.Color) *image.RGBA {
-	data := getText80FromMemory(vs, isSecondPage)
+	data := getText80FromMemory(vs, isSecondPage, false)
 	return renderGr(data, true /*isMeres*/, light)
 }
 

screen/snapshots.go

@@ -46,13 +46,14 @@ func SnapshotPaletted(vs VideoSource, screenMode int) *image.Paletted {
 // See: https://superuser.com/questions/361297/what-colour-is-the-dark-green-on-old-fashioned-green-screen-computer-displays
 var greenPhosphorColor = color.RGBA{65, 255, 0, 255}
 
-func snapshotByMode(vs VideoSource, videoMode uint16, screenMode int) *image.RGBA {
+func snapshotByMode(vs VideoSource, videoMode uint32, screenMode int) *image.RGBA {
 	videoBase := videoMode & VideoBaseMask
 	mixMode := videoMode & VideoMixTextMask
 	isSecondPage := (videoMode & VideoSecondPage) != 0
 	isAltText := (videoMode & VideoAltText) != 0
 	isRGBCard := (videoMode & VideoRGBCard) != 0
 	shiftSupported := (videoMode & VideoFourColors) == 0
+	hasAltOrder := (videoMode & VideoText80AltOrder) != 0
 
 	var lightColor color.Color = color.White
 	if screenMode == ScreenModeGreen {
@@ -67,7 +68,7 @@ func snapshotByMode(vs VideoSource, videoMode uint16, screenMode int) *image.RGB
 		snap = snapshotText40(vs, isSecondPage, isAltText, lightColor)
 		applyNTSCFilter = false
 	case VideoText80:
-		snap = snapshotText80(vs, isSecondPage, isAltText, lightColor)
+		snap = snapshotText80(vs, isSecondPage, isAltText, hasAltOrder, lightColor)
 		applyNTSCFilter = false
 	case VideoText40RGB:
 		snap = snapshotText40RGB(vs, isSecondPage, isAltText)
@@ -106,7 +107,7 @@ func snapshotByMode(vs VideoSource, videoMode uint16, screenMode int) *image.RGB
 		case VideoMixText40:
 			bottom = snapshotText40(vs, isSecondPage, isAltText, lightColor)
 		case VideoMixText80:
-			bottom = snapshotText80(vs, isSecondPage, isAltText, lightColor)
+			bottom = snapshotText80(vs, isSecondPage, isAltText, hasAltOrder, lightColor)
 		case VideoMixText40RGB:
 			bottom = snapshotText40RGB(vs, isSecondPage, isAltText)
 			applyNTSCFilter = false

screen/testScenarios.go

@@ -12,7 +12,7 @@ import (
 
 // TestScenario is the computer video state
 type TestScenario struct {
-	VideoMode     uint16     `json:"mode"`
+	VideoMode     uint32     `json:"mode"`
 	VideoModeName string     `json:"name"`
 	ScreenModes   []int      `json:"screens"`
 	TextPages     [4][]uint8 `json:"text"`
@@ -89,7 +89,7 @@ func (ts *TestScenario) save(dir string) (string, error) {
 }
 
 // GetCurrentVideoMode returns the active video mode
-func (ts *TestScenario) GetCurrentVideoMode() uint16 {
+func (ts *TestScenario) GetCurrentVideoMode() uint32 {
 	return ts.VideoMode
 }
 

screen/text.go

@@ -18,8 +18,8 @@ func snapshotText40(vs VideoSource, isSecondPage bool, isAltText bool, light col
 	return renderText(vs, text, isAltText, nil /*colorMap*/, light)
 }
 
-func snapshotText80(vs VideoSource, isSecondPage bool, isAltText bool, light color.Color) *image.RGBA {
+func snapshotText80(vs VideoSource, isSecondPage bool, isAltText bool, hasAltOrder bool, light color.Color) *image.RGBA {
-	text := getText80FromMemory(vs, isSecondPage)
+	text := getText80FromMemory(vs, isSecondPage, hasAltOrder)
 	return renderText(vs, text, isAltText, nil /*colorMap*/, light)
 }
 
@@ -34,10 +34,16 @@ func snapshotText40RGBColors(vs VideoSource, isSecondPage bool) *image.RGBA {
 	return renderText(vs, nil /*text*/, false, colorMap, nil)
 }
 
-func getText80FromMemory(vs VideoSource, isSecondPage bool) []uint8 {
+func getText80FromMemory(vs VideoSource, isSecondPage bool, hasAltOrder bool) []uint8 {
 	text40Columns := getTextFromMemory(vs, isSecondPage, false)
 	text40ColumnsAlt := getTextFromMemory(vs, isSecondPage, true)
 
+	if hasAltOrder {
+		tmp := text40ColumnsAlt
+		text40ColumnsAlt = text40Columns
+		text40Columns = tmp
+	}
+
 	// Merge the two 40 cols to return 80 cols
 	text80Columns := make([]uint8, 2*len(text40Columns))
 	for i := 0; i < len(text40Columns); i++ {

screen/textToAnsi.go

@@ -6,15 +6,11 @@ import (
 )
 
 // RenderTextModeAnsi returns the text mode contents using ANSI escape codes for reverse and flash
-func RenderTextModeAnsi(vs VideoSource, is80Columns bool, isSecondPage bool, isAltText bool, isApple2e bool) string {
+func RenderTextModeAnsi(vs VideoSource, is80Columns bool, isSecondPage bool, isAltText bool, supportsLowercase bool, hasAltOrder bool) string {
-	//func DumpTextModeAnsi(a *Apple2) string {
-	//	is80Columns := a.io.isSoftSwitchActive(ioFlag80Col)
-	//	isSecondPage := a.io.isSoftSwitchActive(ioFlagSecondPage) && !a.mmu.store80Active
-	//	isAltText := a.isApple2e && a.io.isSoftSwitchActive(ioFlagAltChar)
 
 	var text []uint8
 	if is80Columns {
-		text = getText80FromMemory(vs, isSecondPage)
+		text = getText80FromMemory(vs, isSecondPage, hasAltOrder)
 	} else {
 		text = getTextFromMemory(vs, isSecondPage, false)
 	}
@@ -26,7 +22,7 @@ func RenderTextModeAnsi(vs VideoSource, is80Columns bool, isSecondPage bool, isA
 		line := ""
 		for c := 0; c < columns; c++ {
 			char := text[l*columns+c]
-			line += textMemoryByteToString(char, isAltText, isApple2e, true)
+			line += textMemoryByteToString(char, isAltText, supportsLowercase, true)
 		}
 		content += fmt.Sprintf("# %v #\n", line)
 	}
@@ -49,7 +45,7 @@ $e0-$ff           Low Nor  Low Nor  Low Nor  Low Nor
 ----------------------------------------------------
 */
 
-func textMemoryByteToString(value uint8, isAltCharSet bool, isApple2e bool, ansi bool) string {
+func textMemoryByteToString(value uint8, isAltCharSet bool, supportsLowercase bool, ansi bool) string {
 	// Normal, inverse or flash
 	topBits := value >> 6
 	isInverse := topBits == 0
@@ -61,8 +57,8 @@ func textMemoryByteToString(value uint8, isAltCharSet bool, isApple2e bool, ansi
 
 	// Move blocks
 	value = value & 0x7f
-	if !isApple2e {
+	if !supportsLowercase {
-		// No uppercase
+		// No lowercase
 		value = value & 0x3f
 	}
 	if isFlash || isInverse && !isAltCharSet {

screen/textToString.go

@@ -6,11 +6,11 @@ import (
 )
 
 // RenderTextModeString returns the text mode contents ignoring reverse and flash
-func RenderTextModeString(vs VideoSource, is80Columns bool, isSecondPage bool, isAltText bool, isApple2e bool) string {
+func RenderTextModeString(vs VideoSource, is80Columns bool, isSecondPage bool, isAltText bool, supportsLowercase bool, hasAltOrder bool) string {
 
 	var text []uint8
 	if is80Columns {
-		text = getText80FromMemory(vs, isSecondPage)
+		text = getText80FromMemory(vs, isSecondPage, hasAltOrder)
 	} else {
 		text = getTextFromMemory(vs, isSecondPage, false)
 	}
@@ -21,7 +21,7 @@ func RenderTextModeString(vs VideoSource, is80Columns bool, isSecondPage bool, i
 		line := ""
 		for c := 0; c < columns; c++ {
 			char := text[l*columns+c]
-			line += textMemoryByteToString(char, isAltText, isApple2e, false)
+			line += textMemoryByteToString(char, isAltText, supportsLowercase, false)
 		}
 		line = strings.TrimRight(line, " ")
 		content += fmt.Sprintf("%v\n", line)

screen/videoSource.go

@@ -7,42 +7,43 @@ import (
 
 // Base Video Modes
 const (
-	VideoBaseMask  uint16 = 0x1f
+	VideoBaseMask  uint32 = 0x1f
-	VideoText40    uint16 = 0x01
+	VideoText40    uint32 = 0x01
-	VideoGR        uint16 = 0x02
+	VideoGR        uint32 = 0x02
-	VideoHGR       uint16 = 0x03
+	VideoHGR       uint32 = 0x03
-	VideoText80    uint16 = 0x08
+	VideoText80    uint32 = 0x08
-	VideoDGR       uint16 = 0x09
+	VideoDGR       uint32 = 0x09
-	VideoDHGR      uint16 = 0x0a
+	VideoDHGR      uint32 = 0x0a
-	VideoText40RGB uint16 = 0x10
+	VideoText40RGB uint32 = 0x10
-	VideoMono560   uint16 = 0x11
+	VideoMono560   uint32 = 0x11
-	VideoRGBMix    uint16 = 0x12
+	VideoRGBMix    uint32 = 0x12
-	VideoRGB160    uint16 = 0x13
+	VideoRGB160    uint32 = 0x13
-	VideoSHR       uint16 = 0x14
+	VideoSHR       uint32 = 0x14
-	VideoVidex     uint16 = 0x15
+	VideoVidex     uint32 = 0x15
 )
 
 // Mix text video mdes modifiers
 const (
-	VideoMixTextMask  uint16 = 0x0f00
+	VideoMixTextMask  uint32 = 0x0f00
-	VideoMixText40    uint16 = 0x0100
+	VideoMixText40    uint32 = 0x0100
-	VideoMixText80    uint16 = 0x0200
+	VideoMixText80    uint32 = 0x0200
-	VideoMixText40RGB uint16 = 0x0300
+	VideoMixText40RGB uint32 = 0x0300
 )
 
 // Other video mode modifiers
 const (
-	VideoModifiersMask uint16 = 0xf000
+	VideoModifiersMask  uint32 = 0xf000
-	VideoSecondPage    uint16 = 0x1000
+	VideoSecondPage     uint32 = 0x1000
-	VideoAltText       uint16 = 0x2000
+	VideoAltText        uint32 = 0x2000
-	VideoRGBCard       uint16 = 0x4000
+	VideoRGBCard        uint32 = 0x4000
-	VideoFourColors    uint16 = 0x8000
+	VideoFourColors     uint32 = 0x8000
+	VideoText80AltOrder uint32 = 0x10000
 )
 
 // VideoSource provides the info to build the video output
 type VideoSource interface {
 	// GetCurrentVideoMode returns the active video mode
-	GetCurrentVideoMode() uint16
+	GetCurrentVideoMode() uint32
 	// GetTextMemory returns a slice to the text memory pages
 	GetTextMemory(secondPage bool, ext bool) []uint8
 	// GetVideoMemory returns a slice to the video memory pages

setup.go

@@ -9,23 +9,45 @@ import (
 )
 
 func configure(configuration *configuration) (*Apple2, error) {
-	a := newApple2()
+	var a Apple2
 	a.Name = configuration.get(confName)
+	a.mmu = newMemoryManager(&a)
+	a.video = newVideo(&a)
+	a.io = newIoC0Page(&a)
+	a.commandChannel = make(chan command, 100)
 
 	// Configure the board
 	board := configuration.get(confBoard)
 	a.board = board
-	a.isApple2e = board == "2e"
+
+	err := setupCharactedGenerator(&a, board, configuration.get(confCharRom))
+	if err != nil {
+		return nil, err
+	}
 
 	addApple2SoftSwitches(a.io)
-	if a.isApple2e {
+	switch board {
-		a.hasLowerCase = true
+	case "2plus":
+		a.mmu.initMainRAM()
+	case "2e":
+		a.isApple2e = true
+		a.mmu.initMainRAM()
 		a.mmu.initExtendedRAM(1)
+		a.hasLowerCase = true
 		addApple2ESoftSwitches(a.io)
-	}
+	case "base64a":
-	if board == "base64a" {
+		a.mmu.initMainRAM()
 		a.hasLowerCase = true
 		addBase64aSoftSwitches(a.io)
+	case "basis108":
+		memBasis108 := newMemoryRangeBasis108()
+		videoBasis108 := newVideoBasis108(&a, memBasis108)
+		a.mmu.initCustomRAM(memBasis108)
+		a.video = videoBasis108
+		a.hasLowerCase = true
+		addBasis108SoftSwitches(a.io, memBasis108, videoBasis108, a.cg)
+	default:
+		return nil, fmt.Errorf("board %s not supported it must be '2plus', '2e', 'base64a', 'basis108", board)
 	}
 
 	cpu := configuration.get(confCpu)
@@ -36,12 +58,7 @@ func configure(configuration *configuration) (*Apple2, error) {
 		a.cpu = iz6502.NewCMOS65c02(a.mmu)
 	}
 
-	err := a.loadRom(configuration.get(confRom))
+	err = a.loadRom(configuration.get(confRom))
-	if err != nil {
-		return nil, err
-	}
-
-	err = setupCharactedGenerator(a, board, configuration.get(confCharRom))
 	if err != nil {
 		return nil, err
 	}
@@ -58,7 +75,7 @@ func configure(configuration *configuration) (*Apple2, error) {
 	for i := 0; i < 8; i++ {
 		cardConfig := configuration.get(fmt.Sprintf("s%v", i))
 		if cardConfig != "" {
-			_, err := setupCard(a, i, cardConfig)
+			_, err := setupCard(&a, i, cardConfig)
 			if err != nil {
 				return nil, err
 			}
@@ -81,48 +98,37 @@ func configure(configuration *configuration) (*Apple2, error) {
 	// Add optional accesories including the aux slot
 	ramWorksSize := configuration.get(confRamworks)
 	if ramWorksSize != "" && ramWorksSize != "none" {
-		err = setupRAMWorksCard(a, ramWorksSize)
+		err = setupRAMWorksCard(&a, ramWorksSize)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	if configuration.getFlag(confRgb) {
-		setupRGBCard(a)
+		setupRGBCard(&a)
 	}
 
 	nsc := configuration.get(confNsc)
 	if nsc != "none" && nsc != "" {
-		err = setupNoSlotClock(a, nsc)
+		err = setupNoSlotClock(&a, nsc)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	if configuration.getFlag(confRomx) {
-		err := setupRomX(a)
+		err := setupRomX(&a)
 		if err != nil {
 			return nil, err
 		}
 	}
 
-	err = setupTracers(a, configuration.get(confTrace))
+	err = setupTracers(&a, configuration.get(confTrace))
 	if err != nil {
 		return nil, err
 	}
 
-	return a, nil
+	return &a, nil
-}
-
-func newApple2() *Apple2 {
-	var a Apple2
-
-	a.Name = "Pending"
-	a.mmu = newMemoryManager(&a)
-	a.io = newIoC0Page(&a)
-	a.commandChannel = make(chan command, 100)
-
-	return &a
 }
 
 func (a *Apple2) setClockSpeed(speed string) error {
@@ -152,10 +158,15 @@ func (a *Apple2) SetForceCaps(value bool) {
 }
 
 func (a *Apple2) loadRom(filename string) error {
-	if a.board == "base64a" && filename == "<custom>" {
+	if filename == "<custom>" {
-		// The ROM of the base64a has several file and pages
+		switch a.board {
-		loadBase64aRom(a)
+		case "base64a":
-		return nil
+			return loadBase64aRom(a)
+		case "basis108":
+			return loadBasis108Rom(a)
+		default:
+			return fmt.Errorf("no custom ROM defined for board %s", a.board)
+		}
 	}
 
 	data, _, err := LoadResource(filename)
@@ -170,6 +181,57 @@ func (a *Apple2) loadRom(filename string) error {
 	return nil
 }
 
+const pagedRomChipWindowSize = 0x800                                  // 2 KB
+const pagedRomChipCount = 6                                           // There has to be six ROM chips
+const pagedRomWindowSize = pagedRomChipWindowSize * pagedRomChipCount // To cover 0xd000 to 0xffff
+func loadMultiPageRom(a *Apple2, filenames []string) error {
+	if len(filenames) != pagedRomChipCount {
+		return fmt.Errorf("expected %d ROM files, got %d", pagedRomChipCount, len(filenames))
+	}
+
+	// Load the 6 PROM dumps
+	proms := make([][]uint8, pagedRomChipCount)
+	banks := 1
+	for i, filename := range filenames {
+		var err error
+		proms[i], _, err = LoadResource(filename)
+		if err != nil {
+			return err
+		}
+		pages := len(proms[i]) / pagedRomChipWindowSize
+		if pages > banks {
+			banks = pages
+		}
+	}
+
+	// Init the array of banks
+	romBanksBytes := make([][]uint8, banks)
+	for bank := range romBanksBytes {
+		romBanksBytes[bank] = make([]uint8, 0, pagedRomWindowSize)
+	}
+
+	// Distribute the per chip banks on the full rom banks
+	for _, romData := range proms {
+		for bank := range romBanksBytes {
+			start := (bank * pagedRomChipWindowSize) % len(romData)
+			romBanksBytes[bank] = append(romBanksBytes[bank], romData[start:start+pagedRomChipWindowSize]...)
+		}
+	}
+
+	// Create paged ROM
+	romData := make([]uint8, 0, pagedRomWindowSize*banks)
+	for _, bank := range romBanksBytes {
+		romData = append(romData, bank...)
+	}
+	rom := newMemoryRangePagedROM(0xd000, romData, "Multipage main ROM", uint8(banks))
+
+	// Start with first bank active
+	rom.setPage(0)
+
+	a.mmu.physicalROM = rom
+	return nil
+}
+
 // CreateConfiguredApple is a device independent main. Video, keyboard and speaker won't be defined
 func CreateConfiguredApple() (*Apple2, error) {
 	// Get configuration from defaults and the command line

video.go

@@ -18,28 +18,38 @@ const (
 	shResPageSize     = uint16(0x8000)
 )
 
-// GetCurrentVideoMode returns the active video mode
+type video struct {
-func (a *Apple2) GetCurrentVideoMode() uint16 {
+	a *Apple2
-	isTextMode := a.io.isSoftSwitchActive(ioFlagText)
+}
-	isHiResMode := a.io.isSoftSwitchActive(ioFlagHiRes)
-	is80Columns := a.io.isSoftSwitchActive(ioFlag80Col)
-	isStore80Active := a.mmu.store80Active
-	isDoubleResMode := !isTextMode && is80Columns && !a.io.isSoftSwitchActive(ioFlagAnnunciator3)
-	isSuperHighResMode := a.io.isSoftSwitchActive(ioDataNewVideo)
-	isVidex := a.softVideoSwitch.isActive()
 
-	isRGBCard := a.io.isSoftSwitchActive(ioFlagRGBCardActive)
+var _ screen.VideoSource = (*video)(nil)
-	rgbFlag1 := a.io.isSoftSwitchActive(ioFlag1RGBCard)
+
-	rgbFlag2 := a.io.isSoftSwitchActive(ioFlag2RGBCard)
+func newVideo(a *Apple2) *video {
+	return &video{a}
+}
+
+// GetCurrentVideoMode returns the active video mode
+func (v *video) GetCurrentVideoMode() uint32 {
+	isTextMode := v.a.io.isSoftSwitchActive(ioFlagText)
+	isHiResMode := v.a.io.isSoftSwitchActive(ioFlagHiRes)
+	is80Columns := v.a.io.isSoftSwitchActive(ioFlag80Col)
+	isStore80Active := v.a.mmu.store80Active
+	isDoubleResMode := !isTextMode && is80Columns && !v.a.io.isSoftSwitchActive(ioFlagAnnunciator3)
+	isSuperHighResMode := v.a.io.isSoftSwitchActive(ioDataNewVideo)
+	isVidex := v.a.softVideoSwitch.isActive()
+
+	isRGBCard := v.a.io.isSoftSwitchActive(ioFlagRGBCardActive)
+	rgbFlag1 := v.a.io.isSoftSwitchActive(ioFlag1RGBCard)
+	rgbFlag2 := v.a.io.isSoftSwitchActive(ioFlag2RGBCard)
 	isMono560 := isDoubleResMode && !rgbFlag1 && !rgbFlag2
 	isRGBMixMode := isDoubleResMode && !rgbFlag1 && rgbFlag2
 	isRGB160Mode := isDoubleResMode && rgbFlag1 && !rgbFlag2
 
-	isMixMode := a.io.isSoftSwitchActive(ioFlagMixed)
+	isMixMode := v.a.io.isSoftSwitchActive(ioFlagMixed)
-	isSecondPage := a.io.isSoftSwitchActive(ioFlagSecondPage) && !a.mmu.store80Active
+	isSecondPage := v.a.io.isSoftSwitchActive(ioFlagSecondPage) && !v.a.mmu.store80Active
-	isAltText := a.isApple2e && a.io.isSoftSwitchActive(ioFlagAltChar)
+	isAltText := v.a.isApple2e && v.a.io.isSoftSwitchActive(ioFlagAltChar)
 
-	var mode uint16
+	var mode uint32
 	if isSuperHighResMode {
 		mode = screen.VideoSHR
 		isMixMode = false
@@ -92,7 +102,7 @@ func (a *Apple2) GetCurrentVideoMode() uint16 {
 	if isRGBCard {
 		mode |= screen.VideoRGBCard
 	}
-	if a.isFourColors {
+	if v.a.isFourColors {
 		mode |= screen.VideoFourColors
 	}
 
@@ -100,8 +110,8 @@ func (a *Apple2) GetCurrentVideoMode() uint16 {
 }
 
 // GetTextMemory returns a slice to the text memory pages
-func (a *Apple2) GetTextMemory(secondPage bool, ext bool) []uint8 {
+func (v *video) GetTextMemory(secondPage bool, ext bool) []uint8 {
-	mem := a.mmu.getVideoRAM(ext)
+	mem := v.a.mmu.getVideoRAM(ext)
 	addressStart := textPage1Address
 	if secondPage {
 		addressStart = textPage2Address
@@ -110,8 +120,8 @@ func (a *Apple2) GetTextMemory(secondPage bool, ext bool) []uint8 {
 }
 
 // GetVideoMemory returns a slice to the video memory pages
-func (a *Apple2) GetVideoMemory(secondPage bool, ext bool) []uint8 {
+func (v *video) GetVideoMemory(secondPage bool, ext bool) []uint8 {
-	mem := a.mmu.getVideoRAM(ext)
+	mem := v.a.mmu.getVideoRAM(ext)
 	addressStart := hiResPage1Address
 	if secondPage {
 		addressStart = hiResPage2Address
@@ -120,15 +130,15 @@ func (a *Apple2) GetVideoMemory(secondPage bool, ext bool) []uint8 {
 }
 
 // GetSuperVideoMemory returns a slice to the SHR video memory
-func (a *Apple2) GetSuperVideoMemory() []uint8 {
+func (v *video) GetSuperVideoMemory() []uint8 {
-	mem := a.mmu.getVideoRAM(true)
+	mem := v.a.mmu.getVideoRAM(true)
 	return mem.subRange(shResPageAddress, shResPageAddress+shResPageSize)
 }
 
 // GetCharacterPixel returns the pixel as output by the character generator
-func (a *Apple2) GetCharacterPixel(char uint8, rowInChar int, colInChar int, isAltText bool, isFlashedFrame bool) bool {
+func (v *video) GetCharacterPixel(char uint8, rowInChar int, colInChar int, isAltText bool, isFlashedFrame bool) bool {
 	var pixel bool
-	if a.isApple2e {
+	if v.a.isApple2e {
 		vid6 := (char & 0x40) != 0
 		vid7 := (char & 0x80) != 0
 		char := char & 0x3f
@@ -138,9 +148,9 @@ func (a *Apple2) GetCharacterPixel(char uint8, rowInChar int, colInChar int, isA
 		if vid7 || (vid6 && isFlashedFrame && !isAltText) {
 			char += 0x80
 		}
-		pixel = !a.cg.getPixel(char, rowInChar, colInChar)
+		pixel = !v.a.cg.getPixel(char, rowInChar, colInChar)
 	} else {
-		pixel = a.cg.getPixel(char, rowInChar, colInChar)
+		pixel = v.a.cg.getPixel(char, rowInChar, colInChar)
 		topBits := char >> 6
 		isInverse := topBits == 0
 		isFlash := topBits == 1
@@ -151,13 +161,13 @@ func (a *Apple2) GetCharacterPixel(char uint8, rowInChar int, colInChar int, isA
 }
 
 // GetCardImage returns an image provided by a card, like the videx card
-func (a *Apple2) GetCardImage(light color.Color) *image.RGBA {
+func (v *video) GetCardImage(light color.Color) *image.RGBA {
-	return a.softVideoSwitch.BuildAlternateImage(light)
+	return v.a.softVideoSwitch.BuildAlternateImage(light)
 }
 
 // SupportsLowercase returns true if the video source supports lowercase
-func (a *Apple2) SupportsLowercase() bool {
+func (v *video) SupportsLowercase() bool {
-	return a.hasLowerCase
+	return v.a.hasLowerCase
 }
 
 // DumpTextModeAnsi returns the text mode contents using ANSI escape codes for reverse and flash
@@ -165,5 +175,6 @@ func DumpTextModeAnsi(a *Apple2) string {
 	is80Columns := a.io.isSoftSwitchActive(ioFlag80Col)
 	isSecondPage := a.io.isSoftSwitchActive(ioFlagSecondPage) && !a.mmu.store80Active
 	isAltText := a.isApple2e && a.io.isSoftSwitchActive(ioFlagAltChar)
-	return screen.RenderTextModeAnsi(a, is80Columns, isSecondPage, isAltText, a.isApple2e)
+	supportsLowercase := a.hasLowerCase
+	return screen.RenderTextModeAnsi(a.video, is80Columns, isSecondPage, isAltText, supportsLowercase, false)
 }