Paul Rogers wrote in a message to Matt Mc_Carthy:

 MM> to the PS fan, so that covers that one.  I don't believe
 MM> anything has used the (-5V) line since the days of the 16K
 MM> RAM chips!   :-)

 PR> I know a lot of interfaces have cheated, but RS-232 is supposed to
 PR> be +v to -v, v=5 to 15v or so.

I think that's about the only thing that uses the -12 supply any more,  and
even there,  the task of generating a few mA of -12 with a chip is real
easy these days,  has been for a number of years...   See
"max-232" and similar chips.

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