LCD help

Forum 2005-2010 (read only) General Frequently-Asked Questions
1

So I recently got an LCD to play around with, although i wasnt given any info as to what chip it has, nor how many characters it can hold

all i knw is that it has 16 inline pins.... so i looked up some tutorials, and tried out the 4bit library... and fail... double checked wiring, found some errors in the code as well... and tried again... and fail... so im guessing i still have a wiring problem somewhere, but just in case its something else, can anyone tell me what are the most common problems which arise when wiring/coding an lcd... cause its probably an obvious issue that im just missing...

PS: absolultely nothing is happening on the LCD... if that helps, not even a flicker... :cry:

2

There are some tips that may help in this thread: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238445996/10

3

Two important things to check are :

Did you connect power for the backlight (if the display has one)

Did you connect a potentiometer for the contrast ?

If the contrast i turned all the way down, many displays looks like they are showing nothing.

Do your display have any labels with any letters / numbers on it ?

4

didnt bother with backlight, do i need it?

5

also, although many places say that 16 pin lcd's have a layout of pins as shown here:

http://www.ladyada.net/learn/arduino/lcd.html

(half way down the page)

i found a different place that says the opposite (although it mentions that the backlight is still 15 + 16)

here:

http://www.8052.com/forum/read/72349

which one is correct? i wired it according to the first site, is this right or wrong or wa?!!?!?!?

6

I have LCD panels from a half dozen different manufacturers and I have never seen the pon layout on the LadyAda site. The links in the LCD page in the playground have the more common pinout: Arduino Playground - LCD

You can damage the LCD if you connect the power incorrectly and it wont work correctly if the data and contrast are not correct so try to find the datasheet for your panel.

May not need a backlight to use the LCD but its visibility depends on the technology used in your panel.

7

thanks guys, il get back to this project a little later then, but atleast now i knw were to look

although now there is a chance i already fried the damn thing...