Here we go again...you must define what it is you hope to accomplish and
then determine what resources are available...first! Then you
consider what your options are in choosing the best solution.
Don't feel bad because it's human nature to pick a solution first and
understand what's really needed later. "There's never time to do it right
the first time..." You touch on THE number one pitfall that so many
engineers fall into....and one of the main reasons why projects always
seem to run over budget and can't meet the schedule.

Picking the solution to a problem before the problem is defined or
understood is a BIG mistake. "If were easy, then everybody would do it"

When you figure it all out, stepper motors or a combination of DC motor
with gear reduction mechanism & switch actuators (of which there are many
types). Simple relay logic can be used to reverse the travel.
Good luck!
Westexjoe

On Wed, 20 Jun 2007 23:31:36 +0100, Cableguy wrote:

Hy guys,

Hope all of you are doing ok....

I'm a newbie in mciro-electronics, alrhough I have an electronics course,
i've never worked with PICs before...

I'm trying to design an "actuator" alike circuit, wich would run a dc motor
foward or backward, depending on it's position....Kinda like the CD-Rom draw
does, or a garage door opener....

I'm guessing that to figure the current position out I would have to use
some micro-switch or optic barrier along with one or two relays to invert
the direction....

Anyone ever deone or came across something similar?....

Thanks From Portugal

Paulo Gomes