To that end, he [Jeremy] used the fantastic I2C rotary encoder designed by [fattore.saimon], ... there’s not a whole lot required in the way of wiring or passive components.

We’re digging these daisy-chainable encoders built by [fattore.saimon]. Each module consists of a rotary encoder attached to a PCB with a PIC16F15386 on the back. As we’ve covered in the past… ...

Adafruit has made an I2C interface for four rotary encoders. It comes in the form of a PCB with four footprints that accept one of the most common rotary encoder forms (Bournes PEC11 horizontal style) ...

Encoder technologies abound, but software, wiring, ... How to Customize Magnetic Rotary Encoders with Online Configuration, Software, and Microprocessors. April 24, 2014.