Use modern bluetooth gamepads on your classic MSX computers. Dare to play F1-Spirit with a wiimote wheel?

See github project page for additional information.

Introduction

The msx-joyblue is an adapter that allows connecting Bluetooth controllers to MSX computers using the MSX General Purpose I/O Interfaces (aka joystick ports).

The adapter is based on the unijoysticle2 and bluepad32 projects, both owned by Ricardo Quesada.

The main features of the msx-joyblue v2 adapter are:

• small size
• made of widely available electronic components
• uses SMD components, so good soldering skills are needed to build the adapter
• emulates up to two MSX joysticks
• attaches to MSX computers using female standard DE9 connectors
• formally requires an external USB power supply as the adapter draws slightly more current than two MSX general purpose I/O interfaces can officially provide
• optionally, can be powered using MSX general purpose I/O interfaces without an external power supply if your MSX can safely supply enough current
• builtin leds provide information about the operation of the adapter

Hardware

The msx-joyblue v2 adapter uses an ESP32-WROOM-32E chip to convert the Bluetooth controller actions to the MSX joystick standard signalling.

A two-sided printed circuit board (PCB) is used to put together all components:

• The ESP32-WROOM-32E bluetooth MCU chip
• A CH340C USB to UART chip, to make it easy to upgrade firmware on the ESP32 chip
• A pair of S8050 NPN transistors to control the boot and enable signals of the ESP32 from the CH340C
• An AMS1117-3.3 regulator to convert the 5V from either the USB port or joystick ports to the 3.3V required by the ESP32 chip
• Four 74LS03 quad 2-input NAND gates with open collectors to completely mimic the standard MSX joystick behavior
• A pair of PTC fuses to minimize damage to the MSX computer in case something goes wrong with the board
• Several additional required components (diodes, leds, resistors, ceramic capacitors and an electrolytic capacitor)
• PH2.0 connectors are used to connect cable extensions
• A 2.0 pitch I2C header is added for future extensions
• Jumpers are provided to enable different power options
• A slider switch is used to enable powering the adapter from the MSX side
• Three momentary push buttons are used to reset the board, swap joysticks or change the operation mode

Bill Of Materials

Please, refer to the online BoM for additional information.

The complete BoM is also available for download at PCBWay.

How to Build

See the Build document on the github project page for build instructions.

Firmware

The msx-joyblue v2 adapter firmware uses Ricardo Quesada bluepad32 project to drive Bluetooth controllers. A small modification to the library that enables support for MSX computers has been already committed to the main branch.

See bluepad32 documentation for supported Bluetooth controllers.

Enclosure

A simple acrylic enclosure is included.