I’ve had an Arduino UNO for some time now, but couldn’t come up with a project to put it to use. I recently realized that I have an old Easy Button on my shelf that could probably function as an input device. A Kerbal Space Program launch button comes to mind. :)
I’m sure there are existing recipies for something similar, but my goal is to come up with an original design as a learning experience.
Disassembly reveals a since circuit board that controls the speech that occurs when the button is pressed. I don’t care to utilize the speaker, so for now I will just leave out the batteries.
I need a way to detect a button press, so I set my tested for resistance and touched different spots on the board. When the circled (in red) points are connected, a button press appears to show up as a short.
Detecting a button press
Lacking an electronics starter kit, I found an old redbook audio and asked a friend to crimp some dupont pins. This picture is before I removed the shielding.
As a test, I connected wires to the points on the easy button board and the dupont pins to the analog 0 and ground pins on the arduino. When the button is pressed, the sensor reads 0 as opposed to ~400 when not.
Is the correct way to handle a button? Probably not, at least according to the arduino site. So far this is working so I am sticking to the plan.
I plan on sharing my experience in coaxing the Arduino into behaving as a HID (Human Input Device).
Part 2 is now available.