After using the Arduino microprocessor board for the past year or so, there are often projects that pop into my head unexpectedly that would be perfect for the Arduino. One such project was a desire to display the number of e-mail messages I had received on some type of electronic sign, which happened to be away from my computer. Thus, I needed a wireless way to display information.
It was about this time that I found the Google Radish project. For those that do not know, the Google Radish project was an attempt to display calendar data on conference room doors. The display updated automatically, and used solar power with a wireless connection back to a computer to pull the data. I figured I could replicate this in a slightly modified form with an Arduino. Continue Reading
While working on a project where I needed to display some data, I came across a cholesteric liquid crystal display (ChLCD) from Kent Displays, sold by SparkFun Electronics (LCD-09560, 240 x 160). The unique aspect about this display is that the image is persistent, meaning it has the ability to retain the image on the screen even when the display is no longer powered. This means the device can save power by shutting down the display until the next time an update is needed. The down side is that the display’s refresh time is on the order of two to three seconds. Therefore, it is not suitable for animated graphics, just static images.
After purchasing the display, I attempted to use the sample code provided by SparkFun Electronics. With a minor modification, I was soon able to display alternating vertical bands of black and white bars which proved the display functioned correctly. Now I needed to display my own images. Continue Reading