7 segment LED display driver
Posted on Feb 13, 2013 7056
If you're not familiar with the Arduino, it is `an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software`. It has a small microcontroller, a USB port to connect to your computer for programming, a power socket for providing power when the USB cable isn't connected, and various digital and analog input and output pins, for connecting up to leds, switches and various sensors.
Click here to download the full size of the above Circuit.
It's inexpensive, and there's an open source IDE for programming. Works great, but one issue that I quickly ran into was remembering my circuits. I'd make something up on a breadboard, write a program for it, and then tear it apart to build another circuit. When I wanted to go back to an earlier circuit, I had the program saved, but I couldn't always remember how I had wired up the circuit. So I went looking for a program that would let me document my circuits, and I found Fritzing. It's very easy to use. You drag parts off a palette and connect them up with drag and drop. You can work on a breadboard view or a schematic view, and they are automatically kept in sync. You can easily put bends into wires to route them in more visually appealing ways. Here's an example of a circuit using the Arduino Duemilanove and a 7 Segment Red LED 0.3" Digital Display (RadioShack 276-075). Building this I was able to experiment with another feature of Fritzing, because the 7 Segment LED included in the core parts of the tool was a common anode numerical display. Although these pictures don't show anode/cathode on the pins, it is visible in the tool, and I wanted to get it right. So I edited the part, changed the pin wiring, and saved it as a new part. This was all very straightforward. Then I decided I wanted to have the pins be labeled A, B, C so that it would show up in the schematic view. All the images are SVG, and I didn't...