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RE: NMI on PCI



Electrically, most PCI bus signals are driven by totem-pole CMOS outputs;
they actively drive high when not low.  While you could momentarily short
one to ground and it *might* not blow the IC, this is not considered good
practice and should be avoided.  Some ICs are less tolerant of such faults
and could be damaged.

Many of the control signals (including PERR#) are "sustained tri-state",
meaning that they tri-state at various times, but otherwise they are driven
high or low.  Again, not a good idea to short them to ground.

A few signals are open-drain, including SERR# and the INTx# pins.
Electrically, you should be OK if you shorted any of those pins to ground.

The SERR# pin should be synchronous on the falling edge.  You can't do that
with just a push-button, but it may work well enough for you anyway.

The Interrupt pins are asynchronous, but they are level-sensitive, not
edge-triggered.

Adding extra wires to any pin might induce electrical noise, or create
timing problems.

Regards,
Andy