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Could someone help me identify these pins?
by Super-Hampster on 2011-01-08 (#72491)
This is where the power/RF modulator box connects to the motherboard. I know what 3 out of 5 of the pins do. Could someone help me identify the two other pins which are shown here with a purple box? Sorry for the blurry pic.
Which would have been a good way for hypothetical expansion port peripherals to determine whether they were being powered by an official Nintendo adapter (which puts out 9.0 V AC) or a third-party adapter (for example, the Sega Genesis adapter puts out -9.0 V DC), despite that the NES's regulator is so forgiving.
The expansion port gets the power input after it's rectified, so it is DC there. These are unregulated adapters, so I guess it could be 8V - 18V, or higher maybe.
it's this kind of signal that is outputted on pin 4, should be around 13V DC if using a 9V AC adapter
the post-processing (a cap) isn't really to simulate anything really, it's just to make a steady voltage for the rest of the circuit (reduce the amount of garbage on the input from the "garbage in = garbage out" equation)