So I have the LED hooked up on the far left(purple) then pins D7-D4 through pins 7-4(blue) then is the enable which is in pin 11 the Rw in GND the RS in pin 12 Vo hooked to the middle pin in the potentiometer then 5v and GND. I have power coming from the opposite side of the board from the external breadboard hookup going into the potentiometer and coming out.
heres the code im using ?
*/
// include the library code: #include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12,11,4,5,6,7);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}
void loop() {
// set the cursor to column 0, line 1
// (note: line 1 is the second row, since counting begins with 0):
lcd.setCursor(0, 1);
// print the number of seconds since reset:
lcd.print(millis()/1000);
}
Now everything that I have tried has resulted in the same thing, I can control the contrast with my potentiometer but as soon as the code uploads 1 of 2 things happens either nothing changes and I adjust the contrast to the max and min to check or the bottom line in the all the rectangles of the contrast get a little darker ?
Does anyone see anything wrong here I have hooked the RW to the ground (which has seemed to solve the problem for most people), still nothing for me ? do I have my potentiometer wired incorrectly ? Its running of a 5v/3.3v breadboard power supply in the picture
One possibility is that the excessive current being drawn by your backlight LEDs is dragging down the power supply voltage. All LED backlights require a series resistance but only a few have that resistor on the PC board, and yours is not one of them.
I have tried to move the pins around and I just unplugged the power to the LED to see if that helped I got the one darker bar result ? I have no clue what Im doing wrong here
StrickieZ:
I have tried to move the pins around and I just unplugged the power to the LED to see if that helped I got the one darker bar result ? I have no clue what Im doing wrong here
Man I have tried moving it around on the board like 5 times to check if it was some connection problem and moved the wires all around on the bread board! I still get this weird darker bar every time I upload something ImageShack - Best place for all of your image hosting and image sharing needs I have check double checked and tripple check to make sure everything is connected and connected properly I use the code example in the environment it is /*
LiquidCrystal Library - Hello World
Demonstrates the use a 16x2 LCD display. The LiquidCrystal
library works with all LCD displays that are compatible with the
Hitachi HD44780 driver. There are many of them out there, and you
can usually tell them by the 16-pin interface.
This sketch prints "Hello World!" to the LCD
and shows the time.
The circuit:
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
LCD R/W pin to ground
10K resistor:
ends to +5V and ground
wiper to LCD VO pin (pin 3)
Library originally added 18 Apr 2008
by David A. Mellis
library modified 5 Jul 2009
by Limor Fried (http://www.ladyada.net)
example added 9 Jul 2009
by Tom Igoe
modified 22 Nov 2010
by Tom Igoe
This example code is in the public domain.
*/
// include the library code: #include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}
void loop() {
// set the cursor to column 0, line 1
// (note: line 1 is the second row, since counting begins with 0):
lcd.setCursor(0, 1);
// print the number of seconds since reset:
lcd.print(millis()/1000);
}
and this is my my setup you can zoom and see all the wires and where they go
Does anyone know why I get the weird dark bar and why nothing seems to work is it the breadboard ?
Also in the pic I know im plugged into pins 4,5,6,7 this was right before I moved them over to 2,3,4,5 cause I wanted to see if it made any difference if I changed the pins and code but nothing!
In this case it appears to be an incorrect, or more precisely a missing connection. Since you are using a different power supply for the LCD and for the Arduino you must connect their GND terminals.
Edit: I see that you were told the same thing a few minutes ago by liudr.
you were correct about hooking the ground to the arduino but I still have no output on all the examples ? its like its not even communicating with the board I have repeatedly checked all connections and and moved them around with no results the gnd to arduino fixed the dark bar, I have absolutely no response, I can adjust the contrast but thats about it ? is there any test i can do with a voltmeter or anything why wont this thing work lol ?
How do I go about fixing the falling off screen ? is that bad connections ?, also would it not work if the potentiometer isn't 10k cause I dont know its rating it has a 1 then skwigly then 3 and in regards to the power sucking led's that doesn't seem to be the problem as I unplug them and run code same result (unless the whole thing doesnt work without the led being on for some reason)
rs-pin5 e-pin6 d7-d4--pins10-7 purple is wiper to Vo then powered from arduino.... code: #include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(5,6,7,8,9,10);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}
void loop() {
// set the cursor to column 0, line 1
// (note: line 1 is the second row, since counting begins with 0):
lcd.setCursor(0, 1);
// print the number of seconds since reset:
lcd.print(millis()/1000);
}
In order to properly post code you should cut and paste it as you have done. THEN you should highlight just the code and press the 'code' button which looks like this: '#'.
You should get a new keyboard or at least get the Shift key and the Period keys cleaned.
result with LED OFF contrast all the way up and down
I am having trouble interpreting this. You are stating that the contrast is all the way up, and all the way down. Those are two different situations, yet you have only one photograph. Are you saying that the display looks the same no matter how you adjust the contrast?
You have a nice selection of wires, mostly blue. You will have to separate them so we can follow the connections unambiguously.
What were the results of your voltage measurements?
If your contrast is not changing when you turn your potentiometer, you need to check your potentiometer. Connect your potentiometer wiper to analog pin 0 and run this:
If your reading on the serial monitor goes from 1023 to 0 when you slowly turns the pot, you have a working pot. Anyway, you have not told me what value of pot you are using. The suggested value is 10-25K ohm. I've used 100K ohm once and it worked ok, the contract is just not very stable.
no I turned the contrast all the way up and all the way down to see if there was anything on the screen but nothing apeared ? and the contrast works fine
no I turned the contrast all the way up and all the way down to see if there was anything on the screen but nothing apeared ? and the contrast works fine
This doesn't sound right. Typically something does appear at one of the extremes and this will happen even with the Arduino totally disconnected. If it doesn't, then the contrast does not work fine.
What exactly was the difference in the display when the contrast was all the way up compared to all the way down?
Also, how do you define up and down? Typically the lower voltage (lower as in down) results it the highest contrast (highest as in up).
I'll try again. What were the results of your voltage measurements?
