"A volume control for the PC, I need something like that?" – or rather, "Do not I already have that?" could be the first reactions that occur when reading the title. In fact, there are of course already keyboards with encoder for media control, but maybe not on the favorite keyboard with the great touch feeling. Remedy for this can be with macro and Shortcut software à la AutoHotkey create, or just with a little craft and programming effort.
Our keyboard add-on works with an "endless" rotary encoder, which we have added with an LED ring to indicate the current position. Advantage over a potentiometer: There are also relative settings possible, and also the encoder setting can be easily controlled or programmed remotely. The project is designed to be easily adapted for other purposes requiring quasi-analog input.
- Rotary encoder on the Arduino as Mediaplayer volume control
- Neopixel drive
- Arduino emulates HID keyboard
- Time spent: a weekend
- Costs: 30 to 50 euros for material
- Machinery: 3D printer or laser cutter for housing
- Arduino Leonardo or compatible board with ATmega32U4 CPU, eg. Eg SparkFun Pro Micro
- vibration motor from scrap phone
- Rotary encoder with 24 notches and buttons, z. B. STEC12E08 from ALPS
- Adafruit NeoPixel ring with 12 LEDs, z. From Watterott
- Electronic components Resistors 1 kOhm and 470 ohms, Elko 1000μ / 16V, ceramic capacitor 100n, diode 1N4007, transistor BC547C
Arduino as a keyboard
The idea behind this project can be summarized in the following way: If the keyboard used does not have the corresponding functionality, it simply adds an additional keyboard, which offers this functionality in the form of media keys. A keyboard is recognized by the operating system as such by issuing itself via the USB protocol as HID (Human Input Device). If you now bring any USB device to implement this protocol, you suddenly have an additional "keyboard", which probably would not be immediately recognizable as such.
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. (TagsToTranslate) ATMEGA32U4 (t) Arduino (t) Keyboard (t) Volume