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Last updated on Oct-18-2019 Download

Detect NES-on-a-chip?

Detect NES-on-a-chip?
by on (#61760)
Is it possible for a game to detect if it is running on a NES-on-a-chip hardware with the wrong square duty cycles?

by on (#61762)
You can play a wave by combining writes to $4000 (duty cycle) and $4011 (DAC) such that it's silent on an NES (the values cancel out) but swearing on an NOAC. (The NES can't read that back though.) Or you can exploit timing errors in the PPU; try running some of Blargg's tests on your favorite NOAC.