[sci.electronics] LCD Displays

gbell@pnet12.cts.com (Greg Bell) (12/01/88)

 
    What is the best way to connect to the typical LC display?   These things
have some sort of conductive layer on the glass as "leads" and as far as I can
tell, connecting one of these displays to a breadboarding socket would take a
bit of magic.   Anybody have any ideas?
 
    Also, what good single chip display controllers are there around?  I'm
looking to interface a 16 segment, 16 character LED or LCD alphanumeric
display, and I would really prefer that the 8031 I'm using in the project
could spend its time doing things other than refreshing a display.
 
                                                                 GBell

UUCP: { uunet ncr-sd }!pnet12!gbell
ARPA: crash!pnet12!gbell@nosc.mil
INET: gbell@pnet12.cts.com

gmg@hcx.uucp (Greg M. Garner) (12/02/88)

In article <182@serene.UUCP>, gbell@pnet12.cts.com (Greg Bell) writes:
> 
>     Also, what good single chip display controllers are there around?  I'm
> looking to interface a 16 segment, 16 character LED or LCD alphanumeric
> display, and I would really prefer that the 8031 I'm using in the project
> could spend its time doing things other than refreshing a display.
>  
>                                                                  GBell

How about checking out the Intersil 7106/7107 chips? They control Non
multiplexed LCD and LED displays, 4 digits wide. The LCD version is
built to interface directly to a FE202 or FE203 LCD display. The 
parts can be bought from Jameco Inc. Sorry, but I don't have a 
Jameco catalog handy. Good luck!

   Greg Garner
   501-442-4847
                  USENET:  ...!uunet!harris.cis.ksu.edu!hcx!gmg

coltoff@PRC.Unisys.COM (Joel Coltoff) (12/02/88)

In article <182@serene.UUCP> gbell@pnet12.cts.com (Greg Bell) writes:
>looking to interface a 16 segment, 16 character LED or LCD alphanumeric
>display

Take a look at the HP HDSP-2111 (yellow) or HDSP-2112 (red)
They are eight character smart displays that have built in character
sets, intensity control and flash capability. They are cascadable
so stacked units blink together.
-- 
	- Joel
		{psuvax1,sdcrdcf}!burdvax!coltoff	(UUCP)
		coltoff@burdvax.prc.unisys.com		(ARPA)

mwtilden@watmath.waterloo.edu (M.W.Tilden, Hardware) (12/04/88)

> 
>    What is the best way to connect to the typical LC display?   These things
>have some sort of conductive layer on the glass as "leads" and as far as I can
>tell, connecting one of these displays to a breadboarding socket would take a
>bit of magic.   Anybody have any ideas?

There are two ways I've found to be very effective.  One is to buy some
of those LCD edge-clips which hold on to the selenium (?) contacts by 
spring pressure.  Unfortunately, these are only available in .1 inch
spacing where most modern LCDs have .5 or .02.  Available from large 
electronics distributors like Electrosonic (no plug intended).

The other way I've found really effective, although time consuming, is 
to get a small bottle of Loctite's Quick Grid Repair Resin (available from
most large Automotive/hardware shops where ever snow falls).  This is a 
super conductive paint meant to repair rear-window defogger strips.  Not
only is it a very good conductor (1 or so Ohms per foot) but it's also a 
good adhesive for fixing, say, wire wrap wire to LCD contacts.  The stuff
is quite expensive though; $10 for 1.4 ml and it drys fast, so use it 
sparingly.

The technique I use is to get a hypodermic syringe and needle (fine),
shake the stuff well and fill the syringe with a small quantity of it.
Then quickly run a single conductive line across the well-cleaned contacts
of the LCD.  Give it a few seconds to dry and then use a sharp x-acto
blade to seperate the individual contacts.  After that, rest stripped ends
of wire-wrap wire on the painted contacts and support them so they won't move
(important), then take the syringe again and apply just enough so that 
the wire is covered.  Finally, I finish off by applying a dab of superglue
on top to insure rigidity.  Works great.

I should also point out that this technique also works great for Solar
Cells, so those of you (like me) who went out and bought a pound of broken 
solar cell chips for $30 only to find that you can't solder to the 
suckers, take heart.

Is all.



-- 
Mark Tilden: _-_-_-__--__--_      /(glitch!)  M.F.C.F Hardware Design Lab.
-_-___       |              \  /\/            U of Waterloo. Ont. Can, N2L-3G1
     |__-_-_-|               \/               (519) - 885 - 1211 ext.2454,
"MY OPINIONS, YOU HEAR!? MINE! MINE! MINE! MINE! MINE! AH HAHAHAHAHAHAHAHAHA!!"

gmg@hcx.uucp (Greg M. Garner) (12/06/88)

In article <1341@cseg.uucp>, gmg@hcx.uucp (Greg M. Garner) writes:
> 
> In article <182@serene.UUCP>, gbell@pnet12.cts.com (Greg Bell) writes:
> > 
> >     Also, what good single chip display controllers are there around?  I'm
> > looking to interface a 16 segment, 16 character LED or LCD alphanumeric
> > display, and I would really prefer that the 8031 I'm using in the project
> > could spend its time doing things other than refreshing a display.
> >  
> >                                                                  GBell
> 
> How about checking out the Intersil 7106/7107 chips? They control Non
> multiplexed LCD and LED displays, 4 digits wide. The LCD version is
> built to interface directly to a FE202 or FE203 LCD display. The 
> parts can be bought from Jameco Inc. Sorry, but I don't have a 
> Jameco catalog handy. Good luck!
> 
>    Greg Garner
>    501-442-4847
>                   USENET:  ...!uunet!harris.cis.ksu.edu!hcx!gmg

Ahhh...,  Sorry folks, I must have been brain dead when I wrote this.
The 7106/7107 pair is a A/D convertor with on chip lcd/led drivers. 
The chip needed to hook a 4 digit lcd to a microcontroller is the
7211/7212 series. They drive Non-multiplexed displays, like the 
fe203 lcd or reguler led 7-segment displays. On to answering the 
real question (16 digit display controllers).....

  Intersil also makes some chips to do the 8 and 16 wide displays. 
Some part numbers are: ICM7218  (controls 8 digits of muxed led),
or the ICM7243A, which controls 14-segment 8 wide displays. There is
also the ICM7233/7234 which controls 18-segment 4 wide displays.
I found these and other interesting specs in the intersil applications
handbook. The only phone number I could find on the book is this:

  GE Solid State
  408-996-5000

Hope this clears up any problems my first post caused (Gee, I better
not take any tests in that state of mind....)

  Greg Garner
  501-442-4847
                 USENET: ...!uunet!harris.cis.ksu.edu!hcx!gmg

darel@maccs.McMaster.CA (Darel Mesher) (12/07/88)

In article <182@serene.UUCP>, gbell@pnet12.cts.com (Greg Bell) writes:
> 
>     Also, what good single chip display controllers are there around?  I'm
> looking to interface a 16 segment, 16 character LED or LCD alphanumeric
> display, and I would really prefer that the 8031 I'm using in the project
> could spend its time doing things other than refreshing a display.
>  
>                                                                  GBell

  I built an intelligent controller based on the 8031 family a few
years back and had exactly the same requirements (as well as monetary
constraints ;-) and after much research I used the EPSON family of 
LCD displays.
  The actual device I used was the EA-Y20025AZ (20x2 character display with
dot matrix format).  The beauty of this device is that it is a stand alone
logical block.  The device consists of; complete ASCII character set (as
well as character definition capabilities), single +5V supply, 8 bit data 
bus, standard control signals (ie R/W, Enable, external contrast adjustment),
on-board display ram and it supports many high level s/w commands (Clear 
Display, Return Home, cursor placement and control, auto-increment/decrement 
data buffer entry, read/write from Data RAM and many more).  This particular 
display is relatively cheap (CAN$70 3 years ago) and is only one of a 
family of devices (from 16x1 to 80x4 characters with provisions for easily
cascading multiple displays, also dedicated numerical displays are available).
The quality of the display is excellent (although I can't say the same for the 
Canadian distributors!) and it has been in constant use (24 h/day 365 d/yr) 
for the last 3 years with out any problems...I recommend them highly.

	Just as a side note - if you are going to be doing any S/W 
development for the 8031 family, and are going to be using a PC as
the development system then I would recommend investigating AVOCET's
8031/51/71 cross-assembler and simulator.  I used these tools to 
develop the 6000 lines of assembler code required for my controller. The 
simulator allowed me to develop the S/W and H/W concurrently:- the
system code (approx 95% bug free) was ready before the H/W was completed.
They can be contacted (for a product catalog) at: 

        AVOCET Systems Inc.
        P.O Box 490
        120 Union Street
        Rockport, Maine 04856

Of course I am nothing other than a satisfied customer (of both AVOCET and
EPSON).

Darel.

-- 
Darel Mesher				...!uunet!mnetor!maccs!darel
McMaster University			    darel@maccs.mcmaster.ca

gbell@pnet12.cts.com (Greg Bell) (01/07/89)

 
     A while ago, I posted a question about interfacing to "raw" LC displays. 
To make a long story short, I realized it was too much of a hassle (if it was
possible).   So, I broke down and ended up buying a "ready made" LCD.  
 
 
     The reason I'm posting now is because I got quite a bargain.   A company
called Timeline in Los Angeles is offering GREAT LC displays for $5 each. 
Minimum 5.   They're dot matrix, 16 characters by 1 line (5x7 or 5x10 fonts!
Includes characters with distenders (sp?)).  I bought five, and although I've
only used one, I'm really happy with the thing.  The send a huge packet of
data sheets and app notes along with your purchase.  Although they're used,
they are in good-excellent shape (a few small scratches on the lenses).  The
driver chips are great... basically just send some configuration info, and
start sending your data. 
 
      Anybody interested should contact Timeline at:

                        Timeline
                        1490 West Artesia
                        Gardena, CA, 90247

                        1-800-223-9977
                    or  1-213-217-8912


    I don't see why I should say this, but everybody seems to so here goes: I
am not affiliated in any way with this company!

    Greg Bell_________________________________________________________
      Hardware hacker          |
      Electronics hobbyiest    | UUCP:  uunet!serene!pnet12!gbell
      EE major at UC San Diego |

hack@umbc5.umbc.edu (Mr. Jeffery Hack) (03/11/91)

     I'm looking for LCD displays to use in place of seven
segment LED displays.  There are two main features I am
interested in.  Cost and availability in small quantities.
If any one out there knows where I can find such LCD's I would
appreciate them dropping me a line.

Thanks in advance,
J. Hack
hack@umbc5.umbc.edu