# Arduino adapter lets Sega Genesis controllers work on Philips CD-i

> **Key takeaway:** An open-hardware adapter using an Arduino Pro Micro translates Sega Genesis controller inputs into the serial protocol expected by the Philips CD-i console.

**Published:** 2026-10-21T20:00:14+00:00 
**Source:** Hackaday Hardware 
**Category:** open-hardware 
**Canonical URL:** https://fosswire.org/news/arduino-adapter-lets-sega-genesis-controllers-work-on-philip.html 

## Summary
Hardware hacker MattKC built an adapter to use Sega Genesis controllers on the Philips CD-i, a 1991 multimedia console known for its scarce and poor-quality original controllers. The project uses an Arduino Pro Micro to poll the Genesis pad's simple pinout via DB-9 connector, then translates button states into the serial data stream the CD-i expects from its mouse-like original peripherals. The CD-i's unusual input design, built for pointing devices rather than traditional gamepads, complicates the translation but remains manageable once understood.

## How the adapter bridges two controller eras
- **Arduino Pro Micro** handles protocol translation between Genesis pad and CD-i
- **DB-9 connector** on Genesis side uses simple strobed pin reading for button states
- **CD-i expects serial data stream**, not direct pin states like Atari-compatible ports
- Console was designed for **mouse-like inputs**, requiring translation of directional pad to relative movement data
- **BlueRetro** mentioned as alternative wireless solution for similar retro controller adaptation