izapple2/softSwitches2.go
2019-11-20 23:28:51 +01:00

178 lines
6.0 KiB
Go

package apple2
const (
ioDataKeyboard uint8 = 0x10
ioFlagText uint8 = 0x50
ioFlagMixed uint8 = 0x52
ioFlagSecondPage uint8 = 0x54
ioFlagHiRes uint8 = 0x56
ioFlagAnnunciator0 uint8 = 0x58 // On Copam Electronics Base-64A this is used to bank swith the ROM
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
)
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 take 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
}
func notImplementedSoftSwitchR(*ioC0Page) uint8 {
return 0
}
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
througt the paddle variable resistor to charge a capacitor.
The capacitor is discharged via the strobe softswitch. The result is
hoy 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
}