44 lines
971 B
Go
44 lines
971 B
Go
package system
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const (
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CpuFrequency = 1023000
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AudioSampleRate = 44100
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)
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var (
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PendingInterrupt bool
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PendingNMI bool
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RunningTests bool
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RunningFunctionalTests bool
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RunningInterruptTests bool
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Cycles uint64
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FrameCycles uint64
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AudioChannel chan int16
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LastAudioValue int16
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LastAudioCycles uint64
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AudioAttenuationCounter uint64
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)
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func Init() {
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Cycles = 0
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AudioChannel = make(chan int16, AudioSampleRate*4) // 1 second
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LastAudioValue = 0x2000
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}
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// Handle a write to a magic test address that triggers an interrupt and/or an NMI
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func WriteInterruptTestOpenCollector(address uint16, oldValue uint8, value uint8) {
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oldInterrupt := (oldValue & 0x1) == 0x1
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oldNMI := (oldValue & 0x2) == 0x2
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interrupt := (value & 0x1) == 0x1
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NMI := (value & 0x2) == 0x2
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if oldInterrupt != interrupt {
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PendingInterrupt = interrupt
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}
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if oldNMI != NMI {
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PendingNMI = NMI
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}
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}
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