IRQ and NMI consume 7 CPU cycles

Discuss emulation of the Nintendo Entertainment System and Famicom.

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tepples
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Re: IRQ and NMI consume 7 CPU cycles

Post by tepples »

Two possibilities:

A. It disables NMI before calling the test routine and reenables NMI afterward.
B. The NMI handler doesn't write to any RAM locations that the test routine uses. In a lot of my programs, for example, NMI just increments one location in zero page.
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