Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!rex!ukma!billq
From: billq@ms.uky.edu (fill in blank)
Newsgroups: sci.electronics
Subject: A/D converter ==> PC parallel port?
Keywords: A/D parallel port
Message-ID: <billq.661025394@s.ms.uky.edu>
Date: 12 Dec 90 18:09:54 GMT
Distribution: sci.electronics
Organization: U of Ky, Math. Sciences, Lexington KY
Lines: 20

I am playing with a simple ADC0804 A/D converter.  But I don't have much
data about it. I have enough schematics to let me know what the pin outs
are but thats it.  I am trying to use my PC(XT)'s paralle port to read the
8-bits information from the chip.  I have had some luck reading in from the
OUTPUT lines on the parallel port (i.e. I am breaking some rules ... I guess?).
But this is not working perfectly yet.  I am using transisitors to drive the
port (letting the A/D drive the transistors as switches, then use these to
drive the tri-state parallel port).  Its acting like when it see more then 4
or 5 0 bits, well ... it starts messing up, like maybe its drawing too much
current or somthing?

Any body beed doen this road before?  Any body got a better way of designing
an A/D ==> pc system?

Thanks!

-- 
    Billy Quinn (billq@ms.uky.edu)
                (pr01527@ukpr.uky.edu)
                (home phone: 606-233-1568)