[sdiy] Rotary encoders: is there a clever way to handle many?

[Nils Pipenbrinck]

You can get small FPGA like the Lattice ICE40 chips for around 2$ these
days. They aren't quite small but they have enough logic and IO to
decode 12 rotary encoders and provide a nice SPI or I²C to interface
with a microprocessor.

That's how I would solve this these days.

Best,
  Nils