I've been thru all the posts on this problem! I'm using IDE 1.6.8 and Hello World mod 22 Nov 2010 and Liquid Crystal ver 1.0.3. with the Uno R3. I had this working awhile back and all worked great. I updated libraries and added a DTH 22 to the circuit and it will not work. I can get the DTH working OK. I went back to the basic 1602 lcd Hello World and still will not work. I can get display to view boxes, but no text. I'm using 4 data+ 2 and pwr to uno. I've wired this a number of different ways with different pins. Can I check the Enable and R/W pins with my meter? Do I have to set pins as outputs? Did something change?
Thanks!
No, no and no to your three questions.
Is LCD pin 5 still connected to GND?
Don
I did have pin 5 connected to Gnd, pin 2 vdd 5v, RS pin 0, Enable pin 1, pin 11-14 to uno pin 2-5.
Can I damage this LCD easy?
MadTom544:
I did have pin 5 connected to Gnd, pin 2 vdd 5v, RS pin 0, Enable pin 1, pin 11-14 to uno pin 2-5.
Can I damage this LCD easy?
I'm guessing when you had it working before you were not using Arduino pins 0 and 1.
(Those Arduino pins are used by the serial interface on an Uno R3)
--- bill
I've used any# of different pins, 12, 11 5, 4, 3, 2,. LiquidCrystal lcd(12, 11, 5, 4, 3, 2); and LiquidCrystal lcd(7, 8, 9, 10, 11, 12); Can I check enable and R/w with my meter when running?
Why don't you just post a photograph of your setup and a copy of the program that goes with it so we don't have to keep guessing.
You can check the pins without damaging the circuitry but the results will be meaningless.
Don
OK, I changed the resistor to 220 ohm to pin 15, Gnd to pin 16, Gnd to pin 5.
wire a 10k pot to +5V and GND, with it's wiper (output) to LCD screens VO pin 3
-LCD RS pin to digital pin 12
-LCD Enable pin to digital pin 11
-LCD D4 pin to digital pin 5
-LCD D5 pin to digital pin 4
-LCD D6 pin to digital pin 3
-LCD D7 pin to digital pin 2
It seems the 220 resistor did the trick or maybe rewiring for the fifth time. I had 4.7 k ohm.
All works now!
Thanks for your help!