Hi John,

>|The other is the "SuperIO" parallel port that is built into the motherboard.
>|It can only source 1.2-1.5 mA per pin.  I have driven a 12C508 (which
>|requires 2 mA running at 4 MHz using the internal oscillator) from this port
>|by using the "-SLCT IN" and "-AUTO FD XT" connected through diodes (to
>|prevent backdriving).
>
>I thought it was common for the non-data wires to be open-collector
>with moderate pullips; using them for supplying power would seem
>like it wouldn't be terribly effective.  Have you measured the data
>pins?  Those should be beefier.

I measured 1 mA for sinking and sourcing for this particular PC.  If they
are open-collector/open-drain, doesn't that still indicate that power would
have to be driven external to the card?

myke

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