Reply-To: "Dave M"
From: "Dave M"
Subject: Re: Drive an LCD display _yourself_
X-Newsreader: Microsoft Outlook Express 6.00.2600.0000
X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2600.0000
Date: Sun, 24 Nov 2002 21:50:27 GMT
NNTP-Posting-Date: Sun, 24 Nov 2002 21:50:27 GMT
Organization: AT&T Worldnet
This is certainly the first time I've ever heard of a database having an LCD
display. Are you sure that you know what you have and what you are getting
Giving you the benefit of a doubt, and that was maybe a typo, I'll see if I
can give a few hints.
Since the display is multiplexed, you'll have to build a multiplexer to
handle the segments. You can certainly drive the multiplexer with a PIC,
but the display will need the necessary interface.
This display sounds like a graphical display rather than a character
display. The idea would be to build a mux with the standard row/column
strobe, and the PIC will have to control which columns and rows are turned
on at any given time, thus creating the display. Build the mux so that
columns are strobed high (or low, depending on the display's requirements)
by a serial shift register, which is clocked by the PIC, and then build a
row decoder with binary elements which are set high or low by the PIC, as
required to turn a segment on or off. You will have to add a bit of
circuitry to get the number of control lines down to a number that the PIC
can handle; i.e., a 8 to 256 line decoder.
Dave M firstname.lastname@example.org
Remove the xx for my correct email address
"Charl Linssen" wrote in message
> Hello folks,
> I got a nice LCD display out of a database. it's about (estimated)
> 60x250. Unfortunately, it has no controller built-in, so there are like
> 300 wires coming from it (or whatever).
> Now, I've been expermenting a bit with my home-built variable power
> supply, and I found out that (at 2V) the display appears to be
> multiplexed: rows cathode, columns anode.
> Now, I would just use a pic to drive it, but I don't think there are yet
> any which have 300 (i/)o pins. Any ideas on this?
> -- Charl
> Posted via Mailgate.ORG Server - http://www.Mailgate.ORG