MSX

MSX was a form of standardised computer architecture conceived by one-time Microsoft Japan executive Kazuhiko Nishi as an attempt to create a single industry standard for home computers. Embraced particularly by Japanese electronic manufacturers, any piece of software or hardware that featured the MSX logo was compatible with MSX products of other manufacturers. For example, any MSX expansion or game cartridge would work in any MSX computer.

However, when the MSX was released in the 1980s, the majority of Japanese companies avoided the intensely competitive US home computer market and MSX-based machines were thus seldom seen in the United States. At that time, Europe was the largest computer games (as opposed to console games) market in the world, but by the time the MSX launched in Europe there were already many popular 8-bit home computers, and it was too late to capture the extremely crowded European market.

Although the MSX went on to be the dominant home computer system in Japan and South Korea during the 1980s, and was also popular in Brazil, some Arab countries the Netherlands, Spain and the Soviet Union, it never became the worldwide standard that its makers had envisioned. By the end of its production in 1995, the MSX had sold 5 million units world-wide, compared to its rival, the Commodore 64 (17 million units).

Games

Several popular video game franchises were established on the MSX, including Metal Gear, Bomberman, Puyo Puyo and Parodius. Other games included:

• Aleste
• Castlevania (as Vampire Killer)
• Contra
• Dragon Quest
• Dragon Slayer
• Final Fantasy
• Golvellius
• Gradius (Nemesis)
• Wizardry
• Xak
• Ys
• Zanac

MSX 1 games were mainly published on cassette tape and cartridge; however, as later versions included 3.5" disk drives, the popular media for games and other software shifted to diskettes.

Technical Details

The original MSX standard consisted primarily of several off-the-shelf parts; the graphics chip was a Texas Instruments TMS9918 with 16 KB of dedicated VRAM, the main CPU was a 3.58 MHz Zilog Z80 and the sound was provided by the AY-3-8910 chip manufactured by General Instrument (GI). The system spawned four generations: MSX 1 (1983), MSX 2 (1986), MSX 2+ (1988) and MSX turbo R (1990). Whilst the first three were 8-bit computers based on the Z80 microprocessor, the MSX turbo R was based on an enhanced Zilog Z800 known as the R800.

Specifications for the MSX

Processor

• Zilog Z80A running at 3.58 MHz

ROM

• 32 kB
  • BIOS (16 kB)
  • MSX BASIC V1.0 (16 kB)

RAM

• 8 kB minimum, up to 64 kB

Video

• Display Processor: Texas Instruments TMS9918 family
• Video RAM: 16 kB
• Text modes: 40×24 and 32×24
• Resolution: 256×192 (16 colours)
• Sprites: 32, 1 colour, max 4 per horizontal line

Sound

• Sound chip: General Instrument AY-3-8910 (PSG)
  • 3 channels + noise

Specifications for the MSX 2

Processor

• Zilog Z80A running at 3.58 MHz

ROM

• 48 kB
  • BIOS + Extended BIOS (32 kB)
  • MSX BASIC V2.0 (16 kB)
  • DiskROM (16 kB) (optional)
  • MSX-Audio BIOS (32 kB) (optional)

RAM

• 128 kB (64 kB on Japanese computers, Sony HB-F700P had 256 kB)
  • Memory mapped (4 MB/slot max)

Video

• Video Display Processor: Yamaha V9938 (aka MSX-Video)
• Video RAM: 128 kB (sometimes 64 kB or 192 kB)
• Text modes: 80×24 and 32×24
• Resolution: 512×212 (16 colours out of 512) and 256×212 (256 colours)
• Sprites: 32, 16 colours, max 8 per horizontal line
• Hardware acceleration for copy, line, fill, etc.
• Interlacing to double vertical resolution
• Vertical scroll register

Sound

• Sound chip: Yamaha YM2149 (PSG)
  • 3 channels + noise

Specifications for the MSX 2+

Only officially released in Japan (available in Europe and Brazil via upgrades).

Processor

• Zilog Z80 compatible running at 3.58 MHz or more (5.37 MHz versions were available)

ROM

• 64 kB
  • BIOS + Extended BIOS (32 kB)
  • MSX BASIC V3.0 (16 kB)
  • DiskROM (16 kB)
  • Kun-BASIC (16 kB) (optional)
  • Kanji ROM (optional)

RAM

• 64 kB
  • Memory mapped (4 MB/slot max)

Video

• Video Display Processor: Yamaha V9958 (aka MSX-Video)
• Video RAM: 128 kB
• Text modes: 80×24 and 32×24
• Resolution: 512×212 (16 colours out of 512) and 256×212 (19268 colours)
• Sprites: 32, 16 colours, max 8 per horizontal line
• Hardware acceleration for copy, line, fill, etc
• Interlacing to double vertical resolution
• Horizontal and vertical scroll registers

Sound

• Sound chip: Yamaha YM2149 (PSG)
  • 3 channels + noise
• Optional sound chip: Yamaha YM2413 (OPLL) (MSX-Music)
  • 9 channels FM or 6 channels FM + 5 drums
  • 15 pre-set instruments, 1 custom

Specifications for the MSX turbo R

Only released in Japan.

Processor

• R800 and Zilog Z80 running respectively at 29 MHz and 7.14 MHz

ROM

• 96 kB
  • BIOS + Extended BIOS (48 kB)
  • MSX BASIC V4.0 (16 kB)
  • DiskROM (16 kB)
  • Kun-BASIC (16 kB)
  • Kanji ROM (256 kB)
  • Firmware (4 MB)

RAM

• 256 kB (FS-A1ST) or 512 kB (FS-A1GT)
• Memory mapped (4 MB/slot max)
• Additionally 16 kB (FS-A1ST) or 32 kB (FS-A1GT) of SRAM (battery-powered)

Video

• Video Display Processor: Yamaha V9958 (aka MSX-Video)
• Video RAM: 128 kB
• Text modes: 80×24 and 32×24
• Resolution: 512×212 (16 colours out of 512) and 256×212 (19768 colours)
• Sprites: 32, 16 colours, max 8 per horizontal line
• Hardware acceleration for copy, line, fill, etc.
• Interlacing to double vertical resolution
• Horizontal and vertical scroll registers

Sound

• Sound chip: Yamaha YM2149 (PSG)
  • 3 channels + noise
• Sound chip: Yamaha YM2413 (OPLL) (MSX-Music)
  • 9 channels FM or 6 channels FM + 5 drums
  • 15 pre-set instruments, 1 custom
• Sound chip: PCM
  • 8-bit single channel (no DMA), 16 kHz max using BIOS routines.
  • Microphone built-in
  • Sound chip: MIDI in/out (FS-A1GT only)