MSX

This article is about the home computer family. For other uses, see MSX (disambiguation) and MSX2 (disambiguation).

MSX

Type	Home computer
Release date	27 June 1983 (27 June 1983)
Discontinued	1995 (MSX turboR)
Operating system	MSX-DOS / MSX BASIC
CPU	Zilog Z80 (8-bit) R800
Memory	8 KiB - 64 KiB

MSX is a standardised home computer architecture, first announced by Microsoft and ASCII Corporation on June 16, 1983. It was conceived by Kazuhiko Nishi, then Vice-president at Microsoft Japan and Director at ASCII Corporation. The system was designed to be plug and play, thus requiring no user intervention either on hardware or software to install extensions.

The MSX-based machines were seldom released in the United States, but were popular in Asian, South American, and European countries. To a lesser extent, the MSX platform was also popular in the former Soviet Union and Kuwait. The MSX was released almost at the same time as the Nintendo's Family Computer in the countries where both were marketed, becoming one of Nintendo's main competitors in Japan. It is one of the major platforms for which major Japanese game studios, such as Konami, Sega, Compile, Falcom and Hudson Soft, produced video game titles. The Metal Gear series, for example, was originally written for MSX hardware.

History

The Spectravideo SV-328 was the predecessor of the MSX standard. Many MSX programs were unofficially ported to the SV-328 by home programmers.

In the early 1980s, most home computers manufactured in Japan such as the NEC PC-6001 and PC-8000 series, Fujitsu's FM-7 and FM-8, and Hitachi's Basic Master featured a variant of Microsoft's Basic interpreter integrated into their on-board ROMs. The hardware design of these computers and the various dialects of their ROM Basics were incompatible. Other Japanese consumer electronics firms such as Panasonic, Canon, Casio, Yamaha, Pioneer, and Sanyo were searching for ways to enter the new home computer market.

Nishi proposed MSX as an attempt to create a single industry standard for home computers. Inspired by the success of VHS as a standard for video cassette recorders, many Japanese electronic manufacturers along with GoldStar, Philips and Spectravideo built and promoted MSX computers. Any piece of hardware or software with the MSX logo on it was compatible with MSX products of other manufacturers. In particular, the expansion cartridge form and function were part of the standard; any MSX expansion or game cartridge would work in any MSX computer.

Nishi's standard was built around the Spectravideo SV-328 computer. The standard consisted primarily of several off-the-shelf parts; the main CPU was a 3.58 MHz Zilog Z80, the graphics chip a Texas Instruments TMS9918 with 16 KB of dedicated VRAM, the sound and partial I/O support was provided by the AY-3-8910 chip manufactured by General Instrument (GI), and an Intel 8255 Programmable Peripheral Interface chip was used for the parallel I/O such as the keyboard. This was a choice of components that was shared by many other home computers and games consoles of the period, such as the ColecoVision home computer (an emulator was later available with which MSX systems could run some of its software), and the Sega SG-1000 video game system. To reduce overall system cost, many MSX models used a custom IC known as "MSX-Engine", which integrated glue logic, 8255 PPI, YM2149 compatible soundchip and more, sometimes even the Z80 CPU - however, almost all MSX systems used a professional keyboard instead of a chiclet keyboard, negating the lowered cost of components. Consequently, these components alongside Microsoft's MSX BASIC made the MSX a competitive, though somewhat expensive, home computer package.

Debut

Yamaha YIS503II MSX Personal Computer designed for Soviet schools (notice the abbreviation "КУВТ" which means "Classroom of Educational Computing Equipment)"

The Canon V-20 had 64 KB of RAM while its little brother, the V-10, had 16 KB.

On the 27th June, 1983, the MSX was formally announced during a press conference. A week later, several large Japanese electronics firms announced they would be introducing MSX machines. Among them were industry heavyweights such as Canon, Fujitsu, Hitachi, JVC, Mitsubishi, National, Sanyo, Sony, Toshiba, and Yamaha. Also announcing support for MSX was Korea's Goldstar, now LG, and US-Hong Kong company Spectravideo.

During the previous two decades, Japanese firms dominated a number of industries; watches, cameras, motorcycles, and cars soon followed. More recently, Japanese electronics firms have held a monopoly in stereo systems and televisions, and had largely created and then dominated the home video recorder market. A new wave of anti-Japanese sentiment was taking hold—this time commercial—and there was widespread concern that Western companies would be overtaken.

However, the designs, largely made of commodity parts, were not competitive with the more heavily customised machines from the US and Europe—notably, machines like the Commodore 64. Moreover, the US market was in the midst of the throes of a Commodore-led price war, and machines that had cost approximately $700 in 1981 were now selling for less than $200. The Japanese companies mostly stayed out of the US market. Spectravideo's MSX saw very little success in the US, and Yamaha's CX5M model which built to interface with various types of MIDI equipment, was billed more as a digital music tool than a standard personal computer.

Adoption

During the '80s, Europe became the largest computer games market (as opposed to console games) in the world, and the extremely popular Commodore 64 and Sinclair ZX Spectrum computers dominated. By the time the MSX was launched in Europe, several more popular 8-bit home computers had also arrived, and it was too late to capture the extremely crowded European 8-bit computer market.

A problem for some game software developers was that the method by which MSX-1 computers addressed their video RAM could be quite slow compared with systems that gave direct access to the video memory. This, and the fact that the completely different features the MSX-1's video chip (using the MSX Video access method) had to compensate - the slower video access were not efficiently used while porting mostly Spectrum) software -made the MSX-1 appear slower when running ported games.

Some minor compatibility issues also plagued ported Spectrum games. For example, the Toshiba HX-10 machine was unable to read certain key combinations at the same time, preventing the Spectrum standard of "Q, A, O, P steering", whereas machines by other manufacturers worked correctly. Later ported games tended to use the MSX-1 joystick port or used MSX's official arrow keys and space bar, or offered the option to choose other keys with which to control the program, solving the problem.

A larger problem was that the designers of the MSX standard bank switching protocol did not prescribe to hardware manufacturers in which banks the cartridges and, more importantly, the RAM should be found. Moreover, the MSX's BIOS did not provide this information either, thus requiring programmers to implement complex routines to "find" these resources. Often programmers assumed that the RAM and cartridges would be available at a "default" bank switch location; in reality some systems had their RAM or cartridge slot(s) not at the "default" location, but at another bank switch location. In those cases programs failed to run because they only "saw" 32 KB of the available memory, instead of the full 64 KB that almost all MSX-1 machines offered. All other mainstream MSX-1 machines offered at least the full 64 KB of RAM, with a very few exceptions, such as some early Phillips MSX-1 models (the VG8000 has 16 KB of RAM and the VG8010 has 32 KB) or the Casio PV-7, a low budget MSX targeted for playing games, which has only 8 KB.

Evolution

MSX spawned four generations: MSX (1983), MSX2 (1985), MSX2+ (1988), and MSX TurboR (1990). The first three were 8-bit computers based on the Z80 microprocessor, while the MSX TurboR was based on a custom 16-bit R800 microprocessor developed by ASCII Corporation. By the time the MSX TurboR standard was announced in 1990, only Panasonic was manufacturing MSX computers. Its initial model FS-A1ST met with moderate success, but the upgraded model FS-A1GT introduced in 1991 sold poorly due to its high retail cost of 99800 yen. Production of the TurboR ended in 1993 when Panasonic decided to focus on the release of 3DO.

The MSX3 was scheduled for market in 1990. Delays in the development of its VDP—then named V9978 on the pre-release spec sheets—caused Yamaha to miss its time to market deadline. In its place, an improved MSX2+ was released as the MSX TurboR; features of the new R800 processor such as DMA and 24-bit addressing were disabled. The VDP was eventually delivered two years after its planned deadline, by which time the market had moved on. In an attempt to reduce its financial loss, Yamaha stripped nearly all V9958 compatibility and marketed the resulting V9990 E-VDP III as a video-chipset for PC VGA graphic cards, with moderate success. Sony also employed the V7040 RGB encoder chip on many other products. MSX-FAN Magazine also mentions the then-impressive power of the V9990, being able to compete with much more expensive hardware such as the Sharp X68000.

Impact

The Hotbit, developed by Sharp's Epcom home computer division, was a hit in Brazil

TALENT TPC-310 MSX2 computer, made in Argentina by Telematica (1988), based on a Daewoo design. In Spain they were sold as the "Dynata" brand (in a White case)

A Sakhr (صخر), made in Kuwait and used in Egypt and the Gulf Cooperation Council states. It is a copy of the Yamaha AX120

MSX never became the worldwide standard that its makers had envisioned, mainly because it wasn't successful in the U.S. and the UK. Before MSX's lack of success in these markets became apparent, US manufacturer Commodore Business Machines overhauled its product line in the early 1980s and introduced models such as the Plus/4 and Commodore 16 that were intended to better compete with the features of MSX computers. However, in Japan, South Korea, Argentina, and Brazil, MSX was the paramount home computer system of the 1980s. It was also quite popular in continental Europe, especially in the Netherlands and Spain. Classrooms full of networked Yamaha MSX were used for teaching informatics in school in some Arab countries, the Soviet Union, and Cuba, where they were wildly popular in all government education schools and centers.

As the Cuban government attempted to modernize their studies of computer systems, in 1985, Higher Pedagogical Institutes and some schools of Pre-University Education were supplied with Toshiba and Panasonic MSX systems with resident MSX BASIC language, popularly known as "Intelligent keyboards". Once they proved useful, the Minister of Education continued the process installing similar systems throughout all Secondary (Junior High) centers and finalized it in Elementary schools, adult education institutions and newly nationwide formed “Computer and Electronic Youth Clubs” in 1987. Forming the Computer Clubs allowed the Cuban government to interest and educate the common citizen in computer subjects, since selling these systems, or any other personal private computer, to public was banned. (see: Censorship in Cuba )

In the 1980s, Sakhr (صخر) Computers (Developed by Al Alamiah, a Kuwaiti company), started the production of the first Arabic version of MSX computers. They started producing a Yamaha AX100 and a few other models, including MSX2 and MSX2+. The most popular and affordable model within Arab States of the Persian Gulf was the Sakhr MSX AX170. They were also the first to Arabise BASIC and the MSX LOGO.

Al-Alamiah produced other common models, including AX100, AX123, AX150, AX170, AH200, AX200, AX230, AX235, AX250, AX330, AX350-I, AX350-II, AX355, AX370, AX500, AX550, AX660, and AX990. The only MSX console with a Famicom game slot in the MSX computer is AX330. The user can switch between MSX and Famicom modes by pressing a button on the back of the computer. The other variants, which are compatible with the Sega Mega Drive, are the AX660 and AX990.

Many MSX computers were used during the 1980s in Eastern European (former Eastern Bloc) countries as a tool for subtitling films on VHS, or Betamax cassettes. The MSX computers were used for their simplicity and ability to display prepared titles in real time as superimposed text on mastering tapes.

The MSX arrived in Argentina in late 1984. The most popular model was the Talent MSX DPC-200, based on the Daewoo MSX DPC-200. Other models were the Spectravideo (SVI) 728 and the SVI X´Press, with a 3.5" built-in drive. Later on came the Toshiba and some very few Gradiente models from Brazil. In the late 1987, Talent presented the MSX2 TPC-310 ´Turbo´ in the Argentine market. ´Turbo´ was just a cliche, not referred for MSX2+, also based on Daewoo design. The MSX was a highly successful computer in Argentina as Commodore 64, thanks to impulse educational at national level. The MSX-Logo language was used deeply in the schools. MSXII+ never entered into production in Argentina and MSX ceased in 1990.

In total, 9 million MSX computers were sold in Japan alone, along with 200,000 in the United Kingdom, making it relatively popular but still not the global standard it was intended to be. In comparison with rival 8-bit computers, the Commodore 64 sold 17 million units worldwide in its lifetime, the Apple II sold 6 million units, the ZX Spectrum over 5 million units, the Atari 8-bit sold at least 4 million units, the Amstrad CPC sold 3 million units, and the Tandy TRS-80 Model 1 sold 250,000 units.

One MSX2 machine, Sony "Hit-Bit" HB-G900F desktop computer with the HBI-G900 "Videotizer" genlock module, was launched into space on board of a Russian MIR spacecraft and used as a professional video workstation. Later models, Sony HB-F900 computer and HBI-F900 "AV Creator" module, and HB-G900AP computer and HBI-G900 "Videotizer" module, were widely used as broadcast video workstations in Japan.

Similar systems

The system most similar to the MSX was the Spectravideo SV-328 home computer (Spectravideo even claimed to be MSX compatible in advertisements before the actual launch of MSX systems, but it was in fact not completely compatible with the MSX). This led to a new and short-lived kind of software cracking: converting. Since the MSX games were unplayable on the SV-328 computer, SV-328 crackers developed a method of modifying the (MSX) games to make them work on the SV-328. In most cases this included downloading the MSX BIOS to the SV-328 from tape or floppy disk. Spectravideo later launched the SV-728 which completely adhered to the MSX standard.

The Sega SG-1000, the Memotech MTX and the ColecoVision all have many similarities with the MSX1 standard, but none are really compatible with it. Porting games between those systems is somewhat easy. It was also very common to port games from the ZX Spectrum to the MSX, since both have the same CPU, the Spectrum 128 had the same soundchip, and the ZX Spectrum's graphic mode could be easily emulated on the MSX's screen-2 mode.

Localization

By default MSX machine has hardcoded character set and keyboard return scan code handling algorithm. While MSX in overall has full application software compatibility, at the firmware (BIOS) level coupled with its hardware level, due to minor hardware differences, replacement of the BIOS with another from different PC may render incorrect scan code translations and thus incorrect behavior of the keyboard subsystem for the application software.

Revivals

2001

1chipMSX

In 2001, Kazuhiko Nishi initiated a 'MSX Revival' around an official MSX emulator called MSXPLAYer. This is the only official MSX emulator as all MSX copyrights are maintained by the MSX Association. In 2004, a Dutch company Bazix announced they had become the representatives of MSX Association in Europe, being the English contact for any questions regarding the MSX trademarks, copyrights, and licensing. On October 17, 2006, Bazix launched WOOMB.Net, a website selling MSX games in English and other languages, with a selection of 14 games. In Japan, game sales began earlier, through Project EGG. WOOMB.Net was the English counterpart of this and other Japanese services offered by D4 Enterprise, which also announced in August 2006 the launch of a new MSX2 compatible system called the "one chip-MSX", a system based on an Altera Cyclone EP1C12Q240C8 FPGA. The one chip-MSX" is similar in concept to the C-One, a Commodore 64 clone also built on the basis of a single FPGA chip. The new MSX system is housed in a box made out of transparent blue plastic, and can be used with a standard monitor (or TV) and a PC keyboard. It has two MSX cartridge slots and supports the audio extensions MSX-MUSIC and SCC+. A SD/MMC-flashcard can be used as an external storage medium, emulating a disk drive and can be used to boot MSX-DOS. Due to its VHDL programmable hardware it is possible to give the device new hardware extensions simply by running a reconfiguration program under MSX-DOS. The "one chip-MSX" also has two USB connectors that can be used after adding some supporting VHDL code.

On June 7, 2008, the MSX Resource Center Foundation reported that the MSX trademark had moved from MSX Association to the MSX Licensing Corporation, referring to a Benelux trademark register page of MSX, which names the MSX Licensing Corporation as entitled entity till 28-10-2013. At that time, the website of the MSX Licensing Corporation that they linked to as source, had a text saying 'We are planning to revitalize MSX, the innovative computer platform.' on it. However, the website was later changed to contain only the logo of ITNY & Partners, and a link to ITNY & Partners' English and Japanese websites and has no mention of the MSX Licensing Corporation at all. On June 26, 2008, Bazix reported on their website's front page that they are no longer the representative of MSX Association, due to being unable to achieve their goals of "bringing about the commercial MSX Revival beyond the Japanese borders" and "the transfer of the MSX trademark from MSX Association to MSX Licensing Corporation" and "no outlook on any progress in the Western One Chip MSX project any time soon". As a result of this, WOOMB.Net is taken offline as well, with its website redirecting to the Bazix website, until "a solution free of MSX Association's contributions has been completed". According to their post, they will cooperate with D4 Enterprise and the MSX Licensing Corporation "in one or more retro gaming related projects".

On July 4, 2008, MSX Association's European contact website, which states to be the "only official contact place for MSX Association in Europe", reports that the MSX trademark and copyright has been under the MSX Licensing Corporation holding ever since 1983. It explains that MSX Association, chaired by Dr. Kazuhiko Nishi is the operational division of MSX Licensing Corporation which manages the trademarks, logo and copyrights for MSX. According to the same article, D4 Enterprise "refuse to pay royalties to MSX Association for the use of ESE Artists' Factory's work in 1chipMSX and the software licenses in Project Egg", thus they deal with Kazuhiko Nishi 'directly' through the MSX Licensing Corporation. The article mentions as well the ESE MSX System 3, on which the 1chipMSX (also known as One Chip MSX or OCM) is based.

On July 5, 2008, the MSX Association's Europe website posted an announcement reporting that D4 Enterprise was selling the 1chipMSX illegally. In the same post it is stated that Bazix no longer is their representative in Europe, due to Bazix cutting off their relationship.

2011

Assembled GR8BIT kit

In 2011, AGE Labs announced the launch of a MSX kit called GR8BIT - the do-it-yourself computer for learning purposes, which was licensed by the MSX Licensing Corporation. The kit is priced at $499 and includes all necessary components to assemble a working MSX2 compatible computer, except for an ATX chassis, power supply, floppy drive, hard disk, PS/2 keyboard and monitor. It also comes with assembly and operational manuals and a supplement compiled from vendor and community support (from the "GR8BIT Engineering Community").

Franchises established

The most popular and famous MSX games were written by Japanese software-houses such as Konami and Hudson Soft. Several popular video game franchises were initially established on the MSX:

• Aleste and Zanac (the latter developed and released alongside the original FDS version)
• Bomberman
• Penguin Adventure
• Eggerland
• Metal Gear
• Parodius
• Puyo Puyo

Others got various installments on the MSX, including some titles unique to the system or largely reworked versions of games on other formats:

• Castlevania (as Vampire Killer)
• Contra
• Dragon Quest
• Dragon Slayer
• Final Fantasy
• Gradius (Nemesis)
• R-Type
• Snatcher
• Wizardry
• Xak
• Xevious: Fardraut Saga
• Ys

Manufacturers

Main article: List of MSX compatible computers

MSX

Spectravideo, Philips, Al Alamiah, Sony, Sanyo, Mitsubishi, Toshiba, Hitachi, National, Panasonic, Canon, Casio, Pioneer, Fujitsu General, Yamaha, JVC, Yashica-Kyocera, GoldStar, Samsung/Fenner, Daewoo/Yeno, Gradiente, Sharp/Epcom, Talent, Frael*.

MSX2

Philips, Sony, Sanyo, Mitsubishi, Victor (a.k.a. JVC), National, Panasonic, Canon, Yamaha, Pioneer, ACVS/CIEL*, DDX*, Daewoo/Yeno, NTT, Talent, D4 Enterprise.

MSX2+

Sony, Sanyo, Panasonic, ACVS/CIEL*, DDX*.

MSX TurboR

Panasonic, Takaoka/JBT.

Do-it-yourself MSX

AGE Labs

Note *: Clones or Unlicensed equipment.

System specifications

MSX (first generation)

Technical specifications

The effect of attribute clash when using the 256×192 Highres mode of TMS9918.

• Processor: Zilog Z80A running at 3.58 MHz
• ROM: 32 kB
  • BIOS (16 kB)
  • MSX BASIC V1.0 (16 kB)
• RAM: 8 kB minimum, most machines provided either 32 or 64 kB; machines with 128 kB exist
• Video Display Processor: Texas Instruments TMS9918 family
  • Video RAM: 16 kB
  • Text modes: 40×24 and 32×24
  • Resolution: 256×192 (16 colours). In reality there are just 15 colour tints available, because, just like Sinclair Spectrum there are two codes for black. Unlike the Spectrum however, one of the blacks is actually "transparent", so the MSX video picture could be overlaid on another video signal, for example one from a video disk.
  • Sprites: 32, 1 colour, max 4 per horizontal line
• Sound chip: General Instrument AY-3-8910 (PSG)

MSX2

• Processor: Zilog Z80A running at 3.58 MHz
• ROM: 48 kB
  • BIOS + Extended BIOS (32 kB)
  • MSX BASIC V2.0 or V2.1 (16 kB)
  • DiskROM (16 kB) (optional, common)
  • MSX-Audio BIOS (32 kB) (optional, no machines are known with this BIOS built in)
• RAM: 64 kB minimum, commonly 128 kB in Europe, 64 kB on Japanese computers, machines with up to 512 kB were made. Normally memory mapped (4 MB per slot maximum)
• Video Display Processor: Yamaha V9938 (a.k.a. MSX-Video) Supports all MSX video modes plus:
  • Increased video RAM: 128 KB (sometimes 64 kB)
  • New text mode: 80×24
  • New bitmapped video modes without the attribute clash of MSX 1
  • New resolutions: 512×212 (16 colours out of 512) and 256×212 (256 colours)
  • Increased number of, and more advanced sprites: 32, 16 colours, max 8 per horizontal line
  • Hardware acceleration for copy, line, fill, etc.
  • Interlacing to double vertical resolution
  • A vertical scroll register
  • Vertical and horizontal display offset register
• Sound chip: Yamaha YM2149 (PSG)
• Clock chip: Ricoh RP5C01 (or compatible)
• 3.5 in (89 mm) Floppy disk drive is common

MSX2+

MSX2+ computer: a Panasonic FS-A1WSX

• Only officially released in Japan (available in Europe and Brazil via upgrades)
• Processor: Zilog Z80 compatible running at 3.58 MHz (the MSX2+ models from Panasonic can be set to run on 5.37 MHz by software, but this is not part of the standard)
• ROM: 64 kB
  • BIOS + Extended BIOS (32 kB)
  • MSX BASIC V3.0 (16 kB)
  • DiskROM (16 kB) (optional, very common)
  • Kun-BASIC (16 kB) (optional)
  • Kanji ROM (optional)
• RAM: commonly 64 kB (on Japanese computers), normally memory mapped (4 MB per slot maximum)
• Video Display Processor: Yamaha V9958 (aka MSX-Video) All of MSX2's specifications plus:
  • The minimal video RAM is now 128 kB. Up to 192 kB is supported.
  • a new 256×212 YJK video mode with 19268 simultaneous colors
  • a new 256×212 mixed-YJK/RGB video mode with 12499 simultaneous colors
  • a horizontal scroll register
• Sound chip: Yamaha YM2149 (PSG)
• Optional sound chip: Yamaha YM2413 (OPLL) (MSX-Music)
• Clock chip RP5C01
• 3.5 in (89 mm) Floppy disk drive is very common

MSX Turbo R

• Only released in Japan
• Processor: R800 and Zilog Z80A compatible
  • R800 running at 14.31 MHz (instructions use about 2x less clock ticks than the Z80, so often quoted as 28.6 MHz when comparing with the Z80)
  • Zilog Z80A compatible (embedded in the T9769C MSX-Engine) running at 3.58 MHz for backward compatibility
• 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 Display Processor: Yamaha V9958 (aka MSX-Video) so the same capabilities as MSX2+
• Sound chip: Yamaha YM2149 (PSG)
• Sound chip: Yamaha YM2413 (OPLL) (MSX-Music)
• 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)
• Clock chip
• 3.5 in (89 mm) floppy disk drive

Peripherals

Keyboard

The keyboard is a functionally separate unit which could be connected by non-multiplexed and multiplexed interfaces. Multiplexed keyboard units feature additional data direction line, allowing sending scan line number to the keyboard using same data lines used for return scan code, decreasing overall number of wires between keyboard and machine. Non-multiplexed interface is usually used for internal keyboards (and some external keyboards, like Panasonic CF-3300); multiplexed interface is used for external keyboards (e.g. in Yamaha YIS805 model).

Keyboard is organized as a matrix with maximum 11 input lines and 8 output lines, accounting for maximum 88 keys (including all control, numerical and alphanumerical keys). Each scan line is regularly queried to identify the state of the keys on the line; query speed is identified by the system interrupt frequency. Such organization allows system to sense state of each key, not exhibiting notorious problem with 8042 microcontroller-based keyboards when pressing several keys simultaneously (usually more than 3) generates wrong input characters, or renders inability to sense the press of more keys.

Due to keyboard scan being controlled by the system interrupts, it is one of the troubleshooting hints when MSX machine does not display any image (given correct power is tested to be present) to press CAPS key and see if respective LED toggles. If it does not toggle, system is deemed suffering more serious problem than just lack of image on the screen (i.e. the problem with video cable or video display interface in overall).

Cartridges

MSX standard requires at least 1 cartridge slot, most MSX models have 2. These slots are interchangeable, so in most cases it makes no difference in which slot a cartridge is inserted. The physical connector is a 50 pin (2 x 25 contacts), standard 2.54 mm (0.1 inch) pitch edge connector. Using these cartridge slots, a wide variety of peripherals could be connected.

Regular game cartridges are about the size of an audio cassette (so-called "Konami size"). Despite their higher cost, this was a popular format due to its reliability and ease of use.

Around 1985, Hudson Soft released the credit card-sized Bee Card, which was meant as a cheaper and more convenient alternative to ROM cartridges. But it was a commercial failure, and very few titles were released on the format.

Source files for development of the MSX cartridges are available from AGE Labs for EAGLE.

Floppy disk drives

MSX systems generally did not have a built-in disk drive, so games were published mainly on cartridge and cassette tape. Sony created a battery backed RAM cartridge the HBI-55 "data cartridge" for a few computers of their "Hit-Bit" line of MSX systems, that could be used to store programs or data as an alternative to cassette tapes.

Floppy disk drives were available for MSX however, in the form of a cartridge containing the disk interface electronics and a BIOS extension ROM (the floppy disk drive interface), connected to an external case with the drive. In South-America, many of these systems used a 5.25 in (133 mm) floppy disk drive, but in Europe, mostly the 3.5 in (89 mm) drives were popular. In Japan, some MSX1 systems included a built-in 3.5" disk drive, like Panasonic (earlier named Matsushita) CF-3000. In Europe, a whole range of Philips MSX2 systems NMS 8230, 8235, 8245, 8250 and up features either 360 or 720 Kb 3.5" floppy drives.

In 1985, the MSX2 was released, which systems often (but not always) included a built-in 3.5" disk drive too, and consequently the popular media for games and other software shifted to floppy disks.

The MSX-DOS disk operating system was compatible with CP/M, but had a file system compatible with MS-DOS, and its user commands were also similar to early MS-DOS versions. In this way, Microsoft could promote MSX for home use while promoting MS-DOS based personal computers in office environments.

The MSX 3.5" floppy disks are directly compatible with MS-DOS (although some minor details like file undeletion and boot sector code were different). Like MS-DOS 1, MSX disks (formatted) under MSX-DOS 1 have no support for subdirectories.

MSX-Audio

• Yamaha Y8950, commercially released as:
  • Panasonic: MSX-Audio FS-CA1 (32Kb of SampleRAM, 32KB of AudioROM)
  • Philips: Music Module NMS-1205 (32KB of SampleRAM, no MSX-Audio BIOS)
  • Toshiba: MSX FM-synthesizer Unit HX-MU900 (no sample RAM, no MSX-Audio BIOS)
• 9 channels FM or 6 channels FM + 5 drums. YM3526 compatible.
• ADPCM record and play, with Hardware acceleration
• Can be upgraded to 256 KB of SampleRAM

MSX-Music

• Yamaha YM2413 (OPLL), also known as:
  • MSX-Music (standard name)
  • Panasonic: FM-PAC
  • Zemina: Music Box
  • Checkmark: FM-Stereo-Pak
  • DDX: FMX
  • Tecnobytes: FM Sound Stereo (contains the compatible U3567 chip)
• 9 channels FM or 6 channels FM + 5 drums
• 15 pre-set instruments, 1 custom
• Built-in on many MSX2+ models and as standard on MSX TurboR computers

The LINKS

The LINKS was an online network launched for the MSX in Japan in 1986. To access the network, the MSX required The LINKS modem. It featured several multiplayer online games, including T&E Soft's Daiva Dr. Amandora and Super Laydock, Telenet Japan's Girly Block, and Bothtec's Dires. It also featured several downloadable online games, including Konami's A1 Grand Prix and Network Rally.

Emulation

Main article: List of MSX emulators

MSX computers are emulated on many platforms today. Early on most MSX emulators are (or were) based on the code of the pioneer fMSX, a portable MSX emulator by Marat Fayzullin, but many emulators removed Fayzullin's Z80 emulation code entirely in later versions to avoid legal problems as at the time fMSX wasn't free software. Somewhat later fMSX source code became free to use for non-profit use; however a license was still required for commercial use. On December 31, 2013, the Windows version of fMSX 3.7 was released, free for anyone to use.

The official MSX emulator MSXPLAYer Template:Ja icon is produced by the MSX Association, of which the inventor of the MSX standard, Kazuhiko Nishi, is the president.

As of version 0.146.u, MESS currently supports 90 percent of all MSX Versions.

Wii Virtual Console

In February 2007, Nintendo announced that MSX games will be available for the Wii's Virtual Console in Japan, eventually thirteen in total. Sixteen MSX games became available for the Wii U Virtual Console in Japan on December 25, 2013.

See also

• History of computing hardware
• List of MSX games
• Moonsound
• SymbOS
• Zemmix
• Canon V-20

External links

• Template:Dmoz
• The MSX Resource Center
• The MSX Files
• SCROLL Issue 12: Introducing MSX
• MSX Pro (Portuguese)