We've looked at a few different types of LED displays, but because of the large size and spacing of their pixels they tend to be poor at conveying much information. When you want to display text, one of the simplest ways to do so is with a character LCD (liquid crystal display). These are rectangular displays typically consisting of 1, 2, or 4 lines of 8, 16, or 20 characters each, and are commonly used in radios and other low-cost electronics. Each character is typically made up of a matrix of 5 x 8 pixels, which is enough resolution to display any of the ASCII characters, along with some additional symbols.

For this example, I'm using a 2 x 16 character LCD. It will work with different sizes, but with a width of less than 16 characters, some of the text will be cut off. Character LCDs usually require a 5 V supply, but some companies such as SparkFun sell 3.3 V versions. Either version will work with the BeagleBone, just make sure to hook it up to the correct power supply....