package izapple2 const ( ioDataKeyboard uint8 = 0x10 ioFlagText uint8 = 0x50 ioFlagMixed uint8 = 0x52 ioFlagSecondPage uint8 = 0x54 ioFlagHiRes uint8 = 0x56 ioFlagAnnunciator0 uint8 = 0x58 ioFlagAnnunciator1 uint8 = 0x5a ioFlagAnnunciator2 uint8 = 0x5c ioFlagAnnunciator3 uint8 = 0x5e ioDataCassette uint8 = 0x60 ioFlagButton0 uint8 = 0x61 ioFlagButton1 uint8 = 0x62 ioFlagButton2 uint8 = 0x63 ioDataPaddle0 uint8 = 0x64 ioDataPaddle1 uint8 = 0x65 ioDataPaddle2 uint8 = 0x66 ioDataPaddle3 uint8 = 0x67 // Not real softSwitches. Using the numbers to store the flags somewhere. ioFlagRGBCardActive uint8 = 0x7d ioFlag1RGBCard uint8 = 0x7e ioFlag2RGBCard uint8 = 0x7f ) func addApple2SoftSwitches(io *ioC0Page) { io.addSoftSwitchRW(0x00, keySoftSwitch, "KEYBOARD") // Keyboard io.addSoftSwitchRW(0x10, strobeKeyboardSoftSwitch, "AKD") // Keyboard Strobe io.addSoftSwitchR(0x20, notImplementedSoftSwitchR, "TAPEOUT") // Cassette Output io.addSoftSwitchR(0x30, speakerSoftSwitch, "SPEAKER") // Speaker io.addSoftSwitchR(0x40, notImplementedSoftSwitchR, "STROBE") // Game connector Strobe // Note: Some sources indicate that all these cover 16 positions // for read and write. But the Apple2e takes over some of them, with // the prevention on acting only on writes. io.addSoftSwitchRW(0x50, getSoftSwitch(ioFlagText, false), "TEXTOFF") io.addSoftSwitchRW(0x51, getSoftSwitch(ioFlagText, true), "TEXTON") io.addSoftSwitchRW(0x52, getSoftSwitch(ioFlagMixed, false), "MIXEDOFF") io.addSoftSwitchRW(0x53, getSoftSwitch(ioFlagMixed, true), "MIXEDON") io.addSoftSwitchRW(0x54, getSoftSwitch(ioFlagSecondPage, false), "PAGE2OFF") io.addSoftSwitchRW(0x55, getSoftSwitch(ioFlagSecondPage, true), "PAGE2ON") io.addSoftSwitchRW(0x56, getSoftSwitch(ioFlagHiRes, false), "HIRESOFF") io.addSoftSwitchRW(0x57, getSoftSwitch(ioFlagHiRes, true), "HIRESON") io.addSoftSwitchRW(0x58, getSoftSwitch(ioFlagAnnunciator0, false), "ANN0OFF") io.addSoftSwitchRW(0x59, getSoftSwitch(ioFlagAnnunciator0, true), "ANN0ON") io.addSoftSwitchRW(0x5a, getSoftSwitch(ioFlagAnnunciator1, false), "ANN1OFF") io.addSoftSwitchRW(0x5b, getSoftSwitch(ioFlagAnnunciator1, true), "ANN1ON") io.addSoftSwitchRW(0x5c, getSoftSwitch(ioFlagAnnunciator2, false), "ANN2OFF") io.addSoftSwitchRW(0x5d, getSoftSwitch(ioFlagAnnunciator2, true), "ANN2ON") io.addSoftSwitchRW(0x5e, getSoftSwitch(ioFlagAnnunciator3, false), "ANN3OFF") io.addSoftSwitchRW(0x5f, getSoftSwitch(ioFlagAnnunciator3, true), "ANN3ON") io.addSoftSwitchR(0x60, notImplementedSoftSwitchR, "CASSETTE") // Cassette Input io.addSoftSwitchR(0x61, getButtonSoftSwitch(0), "PB0") io.addSoftSwitchR(0x62, getButtonSoftSwitch(1), "PB1") io.addSoftSwitchR(0x63, getButtonSoftSwitch(2), "PB2") io.addSoftSwitchR(0x64, getPaddleSoftSwitch(0), "PDL0") io.addSoftSwitchR(0x65, getPaddleSoftSwitch(1), "PDL1") io.addSoftSwitchR(0x66, getPaddleSoftSwitch(2), "PDL2") io.addSoftSwitchR(0x67, getPaddleSoftSwitch(3), "PDL3") // The previous 8 softswitches are repeated io.addSoftSwitchR(0x68, notImplementedSoftSwitchR, "CASSETTE") // Cassette Input io.addSoftSwitchR(0x69, getButtonSoftSwitch(0), "PB0") io.addSoftSwitchR(0x6A, getButtonSoftSwitch(1), "PB1") io.addSoftSwitchR(0x6B, getButtonSoftSwitch(2), "PB2") io.addSoftSwitchR(0x6C, getPaddleSoftSwitch(0), "PDL0") io.addSoftSwitchR(0x6D, getPaddleSoftSwitch(1), "PDL1") io.addSoftSwitchR(0x6E, getPaddleSoftSwitch(2), "PDL2") io.addSoftSwitchR(0x6F, getPaddleSoftSwitch(3), "PDL3") io.addSoftSwitchR(0x70, strobePaddlesSoftSwitch, "RESETPDL") // Game controllers reset // For RGB screen modes. Default to NTSC artifacts io.softSwitchesData[ioFlag1RGBCard] = ssOn io.softSwitchesData[ioFlag2RGBCard] = ssOn } func notImplementedSoftSwitchR(io *ioC0Page) uint8 { // Return random info. Some games (Serpentine) used CASSETTE and get stuck if not changing. return uint8(io.apple2.cpu.GetCycles()) } func notImplementedSoftSwitchW(*ioC0Page, uint8) { } func setStatusSoftSwitch(ioFlag uint8) softSwitchW { return func(io *ioC0Page, value uint8) { io.softSwitchesData[ioFlag] = value } } func getStatusSoftSwitch(ioFlag uint8) softSwitchR { return func(io *ioC0Page) uint8 { return io.softSwitchesData[ioFlag] } } func getSoftSwitch(ioFlag uint8, isSet bool) softSwitchR { return func(io *ioC0Page) uint8 { if isSet { io.softSwitchesData[ioFlag] = ssOn } else { io.softSwitchesData[ioFlag] = ssOff } return 0 } } func speakerSoftSwitch(io *ioC0Page) uint8 { if io.speaker != nil { io.speaker.Click(io.apple2.cpu.GetCycles()) } return 0 } func keySoftSwitch(io *ioC0Page) uint8 { strobed := (io.softSwitchesData[ioDataKeyboard] & (1 << 7)) == 0 if io.keyboard != nil { if key, ok := io.keyboard.GetKey(strobed); ok { io.softSwitchesData[ioDataKeyboard] = key + (1 << 7) } } value := io.softSwitchesData[ioDataKeyboard] //fmt.Printf("Key $%02x, %v\n", value, strobed) return value } func strobeKeyboardSoftSwitch(io *ioC0Page) uint8 { result := io.softSwitchesData[ioDataKeyboard] //fmt.Printf("Strobe $%02x\n", result) io.softSwitchesData[ioDataKeyboard] &^= 1 << 7 return result } func getButtonSoftSwitch(i int) softSwitchR { return func(io *ioC0Page) uint8 { if io.joysticks != nil && io.joysticks.ReadButton(i) { return 128 } return 0 } } /* Paddle values are calculated by the time taken by a current going through the paddle variable resistor to charge a capacitor. The capacitor is discharged via the strobe softswitch. The result is how many times a 11 cycles loop runs before the capacitor reaches the voltage threshold. See: http://www.1000bit.it/support/manuali/apple/technotes/aiie/tn.aiie.06.html */ const paddleToCyclesFactor = 11 func getPaddleSoftSwitch(i int) softSwitchR { return func(io *ioC0Page) uint8 { if io.joysticks == nil { return 255 // Capacitors never discharge if there is not joystick } reading, hasData := io.joysticks.ReadPaddle(i) if !hasData { return 255 // Capacitors never discharge if there is not joystick } cyclesNeeded := uint64(reading) * paddleToCyclesFactor cyclesElapsed := io.apple2.cpu.GetCycles() - io.paddlesStrobeCycle if cyclesElapsed < cyclesNeeded { // The capacitor is not charged yet return 128 } return 0 } } func strobePaddlesSoftSwitch(io *ioC0Page) uint8 { // On the real machine this discharges the capacitors. io.paddlesStrobeCycle = io.apple2.cpu.GetCycles() return 0 }