My team and I have been trying to code a 16x2 LCD, but have had no luck so far trying to get it to work. We have been trying to code it on an Arduino Mega and followed several step by step guides to simply display "Arduino" with a blinking cursor, currently the issue is that random characters display and continuously change in the first 4 blocks. We were able to make some progress as characters are finally showing up on the screen, this happened after we pulled out the potentiometer and resisted the anode pin with a 220 ohm resistor as suggested by the Arduino forum. we believe that the wires and listed integers are correct as i checked more than enough times. We used 4-bit mode as suggested by the Arduino website
Hello lkwdranger,
Welcome to the forum.
Please read 'how to use this forum - please read' and post your code (not a photo of your computer screen) as shown in item #7, also a circuit diagram and a photo of your project.
Thank you.
I'm thinking that
We have been trying to code it on an Arduino Mega
which has different pins dedicated to particular tasks, causing unwanted information to show up, causing
..., currently the issue is that random characters display and continuously change in the first 4 blocks.
my suggestion is to cross reference UNO and MEGA pins to see if you are using a pin that is busy doing something else you don't know about.
You shouldn't be aiming at a moving target when you troubleshoot an LCD problem.
Your test program should write some information to the screen once and then not send anything else to the LCD.
This means loop() should be empty (nothing between the{ } brackets).
Don