Glcd Super noob question

Using Arduino Displays
1

Hi everybody, I've recently bought a mega 2560 and it came with a SG12864J4 glcd. I've done a few basic led sketches and have got the hang of it.

Anyway my question is, when trying to use the lcd I cant seem to even get it to light up, I've triple checked my wiring against the data sheet and its all fine.
Is the lcd stuffed and is there anyway to test it? Should the backlight come on if I connect power to power pin and gnd to gnd?

Sorry about the long question, I'm a complete noob to this.

Thanks

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Anyway my question is, when trying to use the lcd I cant seem to even get it to light up, I've triple checked my wiring against the data sheet and its all fine.
Is the lcd stuffed and is there anyway to test it? Should the backlight come on if I connect power to power pin and gnd to gnd?

What information did you come up with when you searched for 'SG12864J4'?

Don

3

When I searched google I found a couple references to it on different sites, a pinout diagram on here, the data sheet that was recommended for it, etc

http://www.google.com.au/search?sugexp=chrome,mod=4&sourceid=chrome&ie=UTF-8&q=SG12864J4

http://www.freedrive.com/file/1620343,sg12864j4.pdf

http://www.arduino.cc/playground/Code/GLCDks0108

First link is a google search, second the datasheet and the third is the pinout on this site.

Is there a quick way to test it? ie just hook up pwr and gnd?

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Is there a quick way to test it? ie just hook up pwr and gnd?

Quick? No.

Try this link Google Code Archive - Long-term storage for Google Code Project Hosting.. I believe this library has a diagnostics sketch that will probably be helpful. Also - look for GLCD related posts by forum member bperrybap, he is the resident GLCD expert.

Don

5

Ok will do thanks heaps

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I guess that is my clue to chime in.

First thing is to make sure you have glcd v3 the older v2 library does not work
on the mega Arduino boards or with Arduino 1.x.

The glcd v3 library includes lots of documentation to assist in hooking up the module
and a bit of information on debugging some common issues.

From looking at the datasheet you linked to, the panel you have uses pinout B so you can
use the table to see which Arduino pins should be wired to which glcd module pins.

If you have any questions about the wiring please ask because miswiring can potentially damage
the glcd or the Arduino.

After it is wired up, run the diag sketch and it will offer additional information on the serial port
that can help diagnose any issues.

As far as the backlight goes, if you hook up the backlight correctly it should light up
without having any other wires connected to the arduino or any software running.
(backlight uses glcd module pins 19+ and 20- )
I'm not sure what current limiting resistor that module needs, if any, so make sure to use
one, at least initially, to avoid potentially damaging the backlight.

Unfortunately for everything else, pretty much all the wiring has to be correct and
the library running on the Arduino for anything else to show up on the glcd.

Oh and one final thing since I've been seeing this quite a bit lately.
Any connections used to the glcd module need to be soldered. I've seen cases where the
glcd module is placed on top of a 20 pin header in a bread board.
This will not work. If using wires or a 20 pin header,
all 20 connections to the glcd module must be soldered to the holes in the glcd module.

--- bill

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Cheers, I haven't yet soldered the connections so that may be part of my problem. I'll give it another crack later on

8

db30:
Cheers, I haven't yet soldered the connections so that may be part of my problem. I'll give it another crack later on

There is no "may" about it. The header pins/wires must be soldered or there will be issues.

--- bill

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