Vital Statistics

The MSX ("Machines with Software eXchangeability") specification was conceived by a group of companies led by Microsoft that saw the need for a common standard architecture in the home computer industry.

Many leading companies were involved, including Goldstar, Philips, and Spectravideo. The MSX logo was used to identify compatibility with the MSX standard between manufacturers of MSX equipment. The MSX specification, announced in 1983, enforced compliant manufacturers to build their machines to specific standards, both in hardware and software, such that programs on one MSX would also work on another.

All computers had the following common hardware:

• Zilog Z80A microprocessor running at 3.6 MHz
• Between 16K and 64K of RAM
• Texas Instruments TMS9918 graphics chip with 16K of dedicated VRAM (video RAM)
• General Instrument AY-3-8910 sound chip
• Intel 8255 Programmable Peripheral Interface chip (used for parallel I/O such as the keyboard)

Many of the above chips were integrated into single-chip designs by MSX manufacturers - these were called MSX-Engine chips. Before Nintendo released their Famicom console, many Japanese games studios focussed their attentions on the MSX.

In May 1984, all member manufacturers were to release their MSX-compatible computers.

The following table lists some of the more common MSX1 machines and their specifications:

The MSX was popular in some areas of the world but in two of the largest, it arrived too late. The USA was in the middle of home computer price war between Commodore, Atari and others, and in the UK the Sinclair ZX Spectrum and Commodore 64 had already beaten almost all rivals out of the industry with market dominance.

Due to difficulties in porting existing games to work with the MSX, and a tendency for MSX video to be rather slow, it met with little success in these two major sectors. However, in Japan, South Korea, Spain, the Netherlands and South America, the MSX sold in great numbers.

Following on from the first specification, simply called "MSX", a further three generations of the standard were released:

MSX2, released in 1985, built on the MSX standard with the following enhancements:

• 48K ROM
• Extended BIOS
• MSX BASIC v2.0 or v2.1
• Disk ROM
• MSX Audio BIOS
• 64K minimum RAM (typically 128K)
• Graphics chip changed to Yamaha V9938 with up to 128K video RAM, supporting 80x24 text mode, new video modes without colour attribute clashes, resolutions up to 512x212 (16 colours) and 256x212 (256 colours), more advanced sprites with 16 colours each
• Hardware acceleration for common graphics commands like fill, line, color, etc.
• Interlacing to double vertical resolution
• A vertical scroll register
• Sound chip changed to Yamaha YM2149
• Clock chip changed to RP5C01
• 3.5" floppy disk drive support

The following table lists some of the more common MSX2 machines and their specifications:

MSX2+, officially released in 1988 in Japan only but available through upgrades in other countries, further expanded the specification:

• MSX BASIC v3.0
• Disk ROM
• Kun-BASIC
• Kanji ROM
• Graphics chip changed to Yamaha V9958, all video RAM at 128K, support for a new high colour video mode in 256x212 with 19,268 colours, a horizontal scroll register.
• Sound chip optionally available was the Yamaha YM2413

MSXturboR (1990), was only available in Japan:

• MSX BASIC v4.0
• 4Mb of Firmware
• 512K or 256K of RAM, with 16K of S-RAM (battery-backed)
• Sound supported MIDI in/out, PCM 8-channel with built-in microphone

MSX, MSX2, and MSX2+ were all built for 8-bit home computers based around the Zilog Z80A microprocessor. MSXturboR was instead based on an enhanced version of the Zilog Z800 known as the R800. By 1990 though, the IBM-PC market was booming, so production of the Turbo R ended in 1995 due to lack of support.

All MSX copyrights are now owned by the MSX Association