[simpits-tech] Driving LED's form the parallel port (?)

[Roy Coates]

On Tue, 2 Nov 2004, Matt Bailey wrote:

>
> 	Hmmmm, driving them just with the parallel port might fry the port, or
> would it just not be enough juice? I guess if I use an external source
> of power I'm gonna have to learn some basic electronics to make it work,
> drat. :P
> 	But yeah, 8 LED's.......that's enough to get me started for sure. Say,
> can you vary the output from the pins individually? Like maybe for
> driving a servo or two.........
>

I've had a chat with a couple of electronics guys, one of whom has already
done this - but a few years ago.

The port _should_ be able to provide enough for very low power LED's but
apparently the ideal method is to use the port to sink the current and
provide power ideally from the PC's own 5v supply.

I might have a better way... I'll know shortly.


--

Roy Coates.
Dept of Engineering.
Liverpool University.
E-Mail: r.coates at liv.ac.uk
Tel: 0151 794 4862