🎮 QC-11 / QX-11 Joystick Port Overview

This page documents technical findings about the joystick ports on the Epson QC-11 / QX-11, based on external research and visual inspection.

🧩 Summary of External Research

A detailed analysis of the QC-11 joystick ports was published by KTJ Dragon in Japanese:

🔗 Original Article (Japanese)
📅 Accessed: August 2025
🖋️ Author: KTJ Dragon

The article explores the compatibility of the QC-11 joystick ports with standard Atari-style 9-pin joystick controllers, as well as the internal signal handling.

📝 Key Points Summarized

The QC-11 appears to support two joystick ports, accessible via DE-9 connectors on the front.
These ports match the Atari joystick wiring standard, similar to the MSX system.
Signals are processed by dedicated I/O ICs, which scan pin status using polling via MS-DOS software.
The joystick functionality was intended for educational software and simple games (e.g., “Flappy”).

📜 Credit & License

This information is based on KTJ Dragon’s article shared under publicly accessible web terms.
Please visit their site for the full article and any updates:
👉 https://ktjdragon.com/nb/misc/atari_qc11