The much-maligned Caps Lock key has been causing problems for decades, and its continued existence is controversial enough that Google decided to drop it all together in their Chromebooks. Until the rest of the industry decides to follow their lead, they’ll likely be no shortage of awkward emails or overly aggressive comments that are the direct result of this treacherous key.
But [Glen Akins] thinks he has the solution. His creation is a tiny little USB notification device that has only one purpose: to make a terrible noise as long as the Caps Lock key is engaged. Think of it like the little indicator LED on your keyboard, but one that makes a terrible screeching noise that you simply can’t ignore. This is made possible by the fact that the Caps Lock status is handled at the OS level rather than the local input device.
The notifier is built around the PIC16F1459, as it allowed him to implement USB 2.0 while keeping the part count low. Beyond the PIC, the board uses a handful of passives and a transistor to drive the buzzer from a PWM signal. To avoid duplicated effort, everything was designed to fit inside the enclosure he already developed for his single-key keyboard that we covered last year. [Glen] and a fellow coworker from Keysight put together an excellent video on the creation and use of the buzzer that you can see after the break.
On the other end of the spectrum, and even smaller, is the “USB Capslocker” which is designed to weaponize this already troublesome feature of your keyboard.