Computer Control

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Tommy volts
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Computer Control

Post by Tommy volts » Tue Oct 29, 2002 1:37 pm

I need to control (turn off and on ) a set of 6 or so relays with my 386 computer. Is there an inexpensive package (software,controller, and relays) available to do this?

russlk
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Re: Computer Control

Post by russlk » Tue Oct 29, 2002 8:02 pm

The GWBASIC command: OUT h,j will send data j to port h. You will have to find out what the parallel port number is, and send data that will put 6 ones on the 8 bit data line. The parallel port should be able to drive 5 volt reed relays. I have not tried this but give it a try.

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frhrwa
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Re: Computer Control

Post by frhrwa » Wed Oct 30, 2002 7:10 am

X10 has all of that stuff.. check them out also..
JESUS”…… don’t leave EARTH without HIM!

mikem
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Re: Computer Control

Post by mikem » Fri Nov 01, 2002 5:24 am

I have done as you have decribed hooking up a bunch of leds to the parallel port and it worked very well. Do you how to do it with the newer computers using Visual Basic? One of my computer friends said the only way is to buy somebody's I/O board and use their subroutines.(at a pretty high cost) Thanks--Mike.

mikem
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Re: Computer Control

Post by mikem » Fri Nov 01, 2002 6:46 pm

Well it has been 10 years ago but here is what I remember and is subject to correction by better memories. Pins 2 thru 9 on the parallel port go high when the out is executed from gwbasic with the out(378, 255) command. 378 is the address of my parallel port and the data 255 (in base 8 obviously) makes all lines go high. There is very little power available here so you must buffer it with opto isolators or something to avoid blowing up your computer.<p>Does anyone know how to do this with Visual Basic without buying an interface board and software?

mikem
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Re: Computer Control

Post by mikem » Fri Nov 01, 2002 6:52 pm

I just re-read the thread here and what Russ said is just what I said in another way. I think he is on the right track. I used opto isolators (instead of reed relays) with 220 ohm resistors in series with the built-in leds to ground to avoid drawing too much current thru the LED's and damaging the port. Hope this helps--thanks-Mike.

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