TRHMSX – The open-source MSX2+ FPGA based clone

Description

MSX computers hold a significant place in computing history, and their legacy continues to be celebrated through innovative approaches like FPGA synthesis. Field-Programmable Gate Arrays (FPGAs) provide a unique platform for recreating the MSX architecture, offering a flexible and efficient way to re-create the hardware.

This FPGA-based MSX2+ hardware represents a straightforward implementation, drawing inspiration from the original 1chipMSX circuit but featuring several enhancements and a new PCB design for improved functionality.

The core of this system is the Cyclone I FPGA, accompanied by a few additional components. The PCB is a 4-layer board measuring 12×15 cm.

• MSX2+ Compatibility: Reproducing the MSX2+ architecture, ensuring compatibility with a wide range of software and games.
• Expanded Memory Options: Choose between 2MB or 4MB of mapped RAM, providing users with flexibility for diverse computing needs and applications.
• 9958 Video Display Processor (VDP): Incorporating the 9958 VDP for sharp graphics and improved visual performance, delivering an authentic MSX experience.
• FM and SCC Sound Capabilities: Featuring FM synthesis and SCC sound to reproduce the iconic audio characteristics of MSX systems, enhancing the overall gaming and multimedia experience.
• Programmable Sound Generator (PSG): Including the original PSG for standard MSX audio output.
• Keyboard Compatibility: Supporting PS/2 keyboards with the option for USB keyboards, providing users with a choice for their preferred input device.
• MicroSD Card Support: Integrating a microSD card slot for convenient storage and easy access to files, games, and software.
• MSX Cartridge Slots: Equipped with two MSX cartridge slots, allowing users to explore a vast library of MSX cartridges for an extended range of applications and games.
• Dual Joystick Ports: Featuring two joystick ports for multiplayer gaming and compatibility with classic MSX peripherals.
• Wireless Network Support: Incorporating wireless network support through the ESP8266, enabling online connectivity and expanding the possibilities for networked applications.
• 12V Cartridge Lines: Providing dedicated 12V lines for cartridges, ensuring compatibility with a variety of peripherals and accessories.
• MIDI Support: Enjoy MIDI tunes by connecting a custom cable to Joystick Port 2.

Attention

Video Output

By default, the TRHMSX is configured for VGA video output at 31Khz (dip switches 2/3 in ON/OFF), which provides the best video quality. This configuration is strongly recommended. The VGA standard is supported by most LED/LCD displays with a DH15 connector. For screens that only support HDMI, you can use an inexpensive VGA-to-HDMI converter to achieve optimal results. The composite video output is offered just for compatibility with older screens and doesn’t offer the best quality. The circuit to equalize the VB_CV signal has been removed for simplicity. That circuit was also not part of the original 1chipMSX computer, and its absence results in a slight pink tint in text modes and more saturated colors when playing games using composite video. This color distortion is expected without the VB_CV correction circuit.

If you need better composite ouput I recommend a VGA2AV adapter that can be purchased on AliExpress.

Keyboard

The TRHMSX is compatible with PS/2 keyboards, either with native PS/2 connectors or USB connectivity. However, it’s important to note that not all USB keyboards are compatible with the TRHMSX; only those implementing the PS/2 protocol over USB are suitable.

Built and tested by The Retro Hacker.

The package contains:

• 1 x TRHMSX computer
• 1 x 8Gb microSD card with MSXDOS2 and tools
• 1 x 5V 2A suitable for mains 127-220V power supply
• 1 x 3D printed + acrylic case in chosen color