Summary

A gadget to add knob input to your computer.

This base and knob are designed to hold an EC11 rotary encoder and a Raspberry Pi Pico.

The EC11 encoder on my print friction fits but you may want to utilize adhesive depending on your printer settings and the fit.

I push the EC11 encoder in fully from the inside and then press fit the knob fully onto the encoder shaft while holding pressure on the encoder from the inside. After the knob is installed depressing the knob fully will set the encoder at just the right height to not rub on the mount and have the minimum gap between the base and knob.

Likewise the base circle just pressure fits into place but adhesive could be used.

The interior cutout for the pi pico USB connector and the end of the pi pico are designed to mate up. Either use hot melt glue to hold the pico in place or install the cable into the pico before snapping on the bottom. As above, use of adhesive such as hot melt glue may be required to get the pico to sit in place during plugging/unplugging of USB cable if your install requires that.

I installed the EC11 with the two outer pins on the 3 pin side routed to holes 19 and 20, the center pin of that side and one of the other side pins are connected together and then also to hole 18 on the pico. The remaining pin on the side of the EC11 with two pins goes to hole 17.

I used Adafruit's code from: https://learn.adafruit.com/custom-hid-devices-in-circuitpython/radial-controller to set my device up as a surface wheel for windows.

Two lines in their example will have to be changed to match the following:

switch = digitalio.DigitalInOut(board.GP13)
encoder = rotaryio.IncrementalEncoder(board.GP14, board.GP15)

Another way to configure the device would be to use the adafruit available at: https://learn.adafruit.com/rotary-encoder

to send specific USB HID events when turning and clicking the knob.

I have tested both sets of code and they work great!