Matrix Orbital Corp

Does any one know of where I might find a GPO only board? I am looking for a board that does exactly what the GPO's on the MO displays do, but I do not have need for an expensive display.

Does any one know if I can just use a serial port? how would I program that? I have heard of this being done, but know nothing about it. Please help.

Thank you.
Knoj[/b]

Well, a parallel port would be so much simpler.

You can look at a parallel port as 8 GPOs if you want, and probelm solved. It would be cleaner to use a driver IC, like an octal buffer, as the interface, so you don't damage the motherboard's port circuitry.

I don't know how you could do it on a serial port without some microcontroller in the mix.

Anyway, in parallel, if you can figure out a way in software to write a word to the parallel port, you have your GPO control software. In *NIX it's easy as falling over, in Windoze it will take a little more effort.

Here's sort of the canonical example of what I was just talking about:
http://casemods.pointofnoreturn.org/cpumeter/

For more info try http://www.angelfire.com/mb/lalim/images/parallel.htm but as to doing this via RS232 would require a lot more work.

FWIW, that guy specs 1kohm resistors, I have serious doubts about whether that would light anything up at all.

(5 - 2) / 0.02 = 150 ohms (typical for red LEDs)
(5 - 3.7) / 0.02 = 65 ohms (typical for blue LEDs)

Works fine on mine - I made that exact circuit for testing stuff on LCDC.

I guess the strategy is "current limiting with a vengeance" with the goal of not frying the port.

Wow, help from the both of you guys! Who could have asked for anything better? Thank you so much. I am in luck, as I was planning on using some relays to actually controll what I needed, as some of the devices will be run off of wall power, I just needed a small voltage to switch with. In addition to that, I was concidering giving up one of my serial devices to have this function, but I have a spare parrallel port!

Thank you guys again!
Knoj.

Damn,

After looking at the link that Linear posted more, I have realized that I wan that too! Crap, now what do I do? Now I have to decide which is more important, or I have to write my own program... Well, it looks like I will have to make the choice now, because writing my own will take a large bit of my time, expecially since I am not an expert programmer by any means! Thank you both again! I am very excited about both ideas!

Knoj.

No problme, althoguh if you get yourself a LK204-PC it has 8 highpower (12v) GPO's on it which can be controlled via LCDC to flash / strobe etc. and it can use a plugin to control the printer port!! Go on make it even better!!!