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Add some comments about the IRQ oddities.
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@ -35,6 +35,15 @@ _outptr: .byte $00, $00
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_endptr: .byte $00, $00
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_endptr: .byte $00, $00
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_mockingBoardSpeechBusy: .byte $00
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_mockingBoardSpeechBusy: .byte $00
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_mockingBoardSpeechPlaying: .byte $00
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_mockingBoardSpeechPlaying: .byte $00
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; This is a JMP instruction followed by the address of the old interrupt vector.
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; It serves two purposes:
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; - The interrupt handler in this file can jump to this location to jump to the
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; old interrupt vector
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; - This code can restore the old vector when the speech code is shutdown
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; Better would be to intergrate into the cc65 IRQ functionality but I found I couldn't
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; make that work for some unknown reason. Instead, this interrupt service routine
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; chains the cc65 one.
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_irqLandingPad: .byte $4C, $00, $00
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_irqLandingPad: .byte $4C, $00, $00
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