My first project- guru advice needed


Thread Starter


Now there is plenty of information out there on PICs, servos, steppers, etc. My problem is that my project is targeted at teaching linux programming in developing countries- and thus our budget is like zero :)

So i want to make it as cheap as possible. Any ideas? Thanx.

Ok i've done some research. I have to admit that i am not experienced in engineering, so please explain stuff you think is simple :)

Need to turn a small 3-7 volt motor on and off.

It seems that the cheapest way to turn something on and off by a signal from pc is to use a relay. I don't need feedback, so it's gonna be centronics.

If you have a link to say "a project to turn a led on and off " that is simple, that would be the answer to my question :)

Use a relay? It's probably easier than using servos or steppers and controllers and all, right?

1) which relay do i choose? hopefully under $2, found in old vcrs or toasters :)

2) how do i connect it- which pins of the LPT?

3) which signals to send /will be using c or perl/

Thank you for your time.
Find the Coffee mini-HOWTO, it'll tell you everything you want to know. Probably it's on your disk in /usr/doc/HOWTO/mini or you can get it from the Linux Documentation Project.

> Use a relay?

The Coffee mini-HOWTO has a circuit diagram for driving a relay from the printer port (resistor, NPN transistor and a diode across the relay coil).

Make sure your relay contacts are rated for DC and the current you want.


Jiri Baum <[email protected]>
MAT LinuxPLC project --- --- Machine Automation Tools
For Pete:

If you are in the USA go to Radio Shack, or their parent company Tandy
Corp, and buy their "Green" primer:

Getting Started in Electronics"
Author, Forest M. Mims, II
RS Cat No, 62-5003

Phil Corso, PE
(Boca Raton, FL)