mirror of https://github.com/irmen/ksim65.git
38 lines
1.1 KiB
Kotlin
38 lines
1.1 KiB
Kotlin
package net.razorvine.ksim65.components
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import net.razorvine.ksim65.Petscii
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/**
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* A parallel output device (basically, prints bytes as characters to the screen)
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* First address = data byte (8 parallel bits)
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* Second address = control byte (bit 0 high = write byte)
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*/
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class ParallelPort(startAddress: Address, endAddress: Address) : MemMappedComponent(startAddress, endAddress) {
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var dataByte: UByte = 0
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init {
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require(endAddress - startAddress + 1 == 2) { "parallel needs exactly 2 memory bytes (data + control)" }
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}
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override fun clock() {}
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override fun reset() {}
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override operator fun get(address: Address): UByte {
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return if (address == startAddress)
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dataByte
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else
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0
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}
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override operator fun set(address: Address, data: UByte) {
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if (address == startAddress)
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dataByte = data
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else if (address == endAddress) {
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if ((data.toInt() and 1) == 1) {
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val char = Petscii.decodeScreencode(listOf(dataByte), false).first()
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println("PARALLEL WRITE: '$char'")
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}
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}
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}
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}
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