On Sun, 12 Oct 2003 03:11:09 -0000, ghidera2000 <
ghidera2000@...>
wrote:
> I'm just finishing up the design for an A3977SED based controller board
> but I'm a bit confused about the parallel port connections.
>
> Can the parallel port drive logic high and low or does it just go active
> low (sinking) and high-Z? i.e. Do I need pullups to generate logic high,
> or can the parallel port handle this just fine?
>
> I plan on pulling Enable high on the board and setting it to active low
> in the software. That way if the cable pops out I know the drives will
> stop.
>
>
parallel port drives high..
I know some which have connected leds direct to it and it survived..
so it is current limited somehow.
if i remember correct on old mainboards one could see the pullups (&replace
them)
You need no external pullups..
(This is only MY experience, not any standards or something, just what i
saw on various ports)
st