Z80 interrupts

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IRQ

Chipicon.png Z80 IRQs can be generated by the Chipicon.png YM2610's timers, and are mostly used to time music playback.

The vector address is $0038.

They can be disabled in software (DI/EI) and must be acknowledged via the YM2610.

NMI

Non Maskable Interrupts are triggered when the Chipicon.png 68k sends a sound command.

The vector address is $0066.

They can be enabled or disabled through ports $08 and $18. They are disabled after a reset.

They are acknowledged by reading port $00.