Monday, December 26, 2011

Simple LCD Character Display and Arduino Uno

It is easy to hook up and use a character display to an Arduino. Turns out, a specific driver that comes with LCD displays that is very common is the HD44780 driver and there is an Arduino library specifically for it: LiquidCrystal.

It is very easy to use in software and in hardware. The following picture is from the documentation for my screen that I bought on eBay (JHD-204A), showing the pin configuration and power characteristics.

The official Arduino documentation on LiquidCrystal is all you need and it can be found at: Actually no other parts than connecting wires are required. The potentiometer mentioned in the above reference is just for contrast adjustment.

I personally prefer wire wrapping to soldering when I can, mainly because I am not good at soldering and I do not like toxic fumes. Here I had to solder the header pins onto the LCD display pins, but after that wire wrapping all the way. It was fun. Wire wrapping wire and header pins are an awesome combination.

One inevitably runs into errors when installing the driver for the Arduino Uno on my Windows 7 PC. I thought it was just an error on my computer specifically but apparently it is the norm for now. The solution is found on the official Arduino website here. They acknowledge that the error occurs no matter what, "despite [Window's] best efforts".


  1. Hey,
    I bought the same LCD (JHD 204A) but I can't see characters in 3rd and 4th row, here is the link to image I captured
    Please tell me if its broken or something else needs to be done

  2. Hmmm yes the third and fourth row do look weird in that there are no black dim squares where the characters show. My first guess would be that they are broken, as long as your software does not do anything weird.