Help needed with 16x2 lcds

Projects General Guidance
1

Hey guys,
I have run the code found in http://arduino.cc/en/Tutorial/LiquidCrystal. But for some reason I cannot see anything displayed on the LCD, accept 16 black rectangles. So, anyone have an idea what the problem could be. The black boxes does hade when I turn the potentiometer. Also is there anyway I can use lcd display with breadboard without soldering headers. Hope to get some help.

Thanks.

2

Provide us a web link to the LCD you purchased, some high resolution pictures of the display, how you connected it at the display and at the arduino. You have to solder headers to the LCD. There is no other way to connect it to anything else.

3

yaantey:
Hey guys,
I have run the code found in http://arduino.cc/en/Tutorial/LiquidCrystal. But for some reason I cannot see anything displayed on the LCD, accept 16 black rectangles. So, anyone have an idea what the problem could be. The black boxes does hade when I turn the potentiometer. Also is there anyway I can use lcd display with breadboard without soldering headers. Hope to get some help.

Thanks.

Check your wiring and connections carefully. Did you remember to connect the R/W pin to ground?

I don't know of a reliable way of using these lcd displays with a breadboard other than soldering either a header or some flying leads to them.

4

Hey,

These could be the possible problems,

  1. Check to see ground is connected properly

  2. Make sure you check the DATA SHEET of YOUR lcd display(google the model no.). The lcd i have for eg. has a different pin configuration.

Hope this helps

5

Behind the lcd its written VCM162A as model number. As for wiring I have checked several times. Im yet to see any problem. I have soldered headers to LCD display. Specifically to (1,2,3,4,5,6,11,12,13,14) in the LCD display. I didnt solder other pins since they arent used according to the diagram in arduin website.

6

Is there anyway I can test with multimeter if the headers are soldered correctly with the LCD?

7

If you are using an uno board maybe this will help you.

http://arduino.cc/forum/index.php/topic,76395.0.html

8

I think so. connect the multimeter to header and ground of lcd.. multimeter mode should be the diode beeper one.

9

I can't find the data sheet!!!!.. It is most probably a pin config problem..!!!!

10

Here is the pin configuration. Its the standard one. http://www.engineersgarage.com/electronic-components/16x2-lcd-module-datasheet

Also whats with the Pin 4 and 7 having problem with lcd and resestting arduino.

11

Also whats with the Pin 4 and 7 having problem with lcd and resestting arduino.

Pin 4 should be high.
Some pins may be short circuiting.

Are you sure this is the pin config?

12

I was NOT refering to pins 4 and 7 on the LCD but to the pins 4 and 7 on the UNO.

13

Ok, Then prolly they are shorting. Check to see that.

14

Also is there anyway I can use[a] lcd display with[a] breadboard without soldering headers[?]

You can solder solid core wire to the contacts and attach the other sides of the wire to the breadboard.

15

I just plugged the lcd directly into the breadboard. Worked for me. Try that out!