SoundMachine Build Log 02

I've decided to put in a knob to control the volume directly on the box itself. It will be controlled by volumio itself via a plugin, much like the GPIO Buttons plugin.

Since this is really a development kit approach, the hardware consists of:

• A KY-040 rotary encoder and
• A screw-based prototype board

Both are relatively easy and cheap to find and buy.

Rotary encoder

The encoder is straight-forward cheap version, with a push button too, just in case. It's even mounted on a PCB and has pins too, so it's practically plug-and-play

The prototype board

The board looks like this:

This allows me to connect the clock pin (volume UP), data pin (volume DOWN) to e.g. D7 (GPIO23) and D8 (GPIO24) respectively. Now, we only need to create a plugin to put the encoding in the right place. Next post will detail the software side of volume control :)

Annex - Mapping

The mapping between raspberry pi pins, GPIO and the screw-able parts is: