Editing DOS/V (section)

==History==
In the early 1980s, [[IBM Japan]] developed two [[x86]]-based personal computer lines for the Asia-Pacific region, [[IBM 5550]] and [[IBM JX]]. The 5550 reads Kanji fonts from the disk, and draws text as graphic characters on 1024×768 high resolution monitor. The JX extends [[IBM PCjr]] and [[IBM PC]] architecture. It supports English and Japanese versions of [[PC DOS]] with 720×512 resolution monitor. Both machines couldn't break dominant NEC's PC-98 in consumer market in Japan. Because the 5550 was expensive, it was mostly sold for large enterprises who used IBM's [[mainframe]]. The JX used [[Intel 8088|8088]] processor instead of faster [[Intel 8086|8086]] processor because IBM thought a consumer-class JX mustn't surpass a business-class 5550.<ref name="TheBASIC_1993"/> It damaged buyer's reputations whatever the actual speed was. In another point, a software company said IBM was uncooperative for developing JX software.<ref name="IBM_19860210"/> IBM Japan planned a 100% [[IBM Personal Computer/AT|PC/AT]] compatible machine codenamed "JX2", but cancelled it in 1986.<ref name="TheBASIC_1993"/><ref name=":6"/>

Masahiko Hatori {{Nihongo|2=羽鳥 正彦}} was a developer of JX's DOS. Through the development of JX, he learned the skills needed to localize an English computer into Japanese. In 1987, he started developing the DOS/V during spare time at [[IBM Yamato Facility|IBM Yamato Development Laboratory]]. He thought the 480-line mode of VGA and a processor as fast as the [[Intel 80386|80386]] would realize his idea, but they were expensive hardwares as of 1987. In this era, [[Toshiba]] released the [[J-3100]] laptop computer, and [[Microsoft]] introduced the [[AX architecture]]. IBM Japan didn't join in the AX consortium. His boss, Tsutomu Maruyama {{Nihongo|2=丸山 力}}, thought IBM's headquarters wouldn't allow to adopt the AX because they requested IBM Japan to use the same standard as worldwide IBM offices used.<ref name="NKS_2000_4-532-16331-5"/> In October 1987, IBM Japan released the PS/55 Model 5535 which was a proprietary laptop using a special version of DOS. It was more expensive than the J-3100 because its [[LCD]] display used a non-standard 720×512 resolution. Hatori thought IBM needed to shift their own proprietary PC to IBM PC compatibles. Maruyama and [[Nobuo Mii]] thought Japan's closed PC market needed to be changed and this attempt couldn't be done by IBM alone. In summer of 1989, they decided to carry out the development of DOS/V, disclose the architecture of PS/55, and found the [[PC Open Architecture Developers' Group]] (OADG).<ref name="AsahiPC_19950401"/>

The DOS/V development team designed the DOS/V to be simple for better [[scalability]] and compatibility with original PC DOS. They had difficulty reducing text drawing time. "A stopwatch was a necessity for DOS/V development", Hatori said.<ref name="Hatori_DOSV"/>

IBM Japan announced the first version of DOS/V, IBM DOS J4.0/V, on 11 October 1990, and shipped out in November 1990. At the same time, IBM Japan released the PS/55 Model 5535-S, a laptop computer with VGA resolution. The announcement letter stated DOS/V was designed for low-end desktops and laptops of PS/55,<ref name="IBM_1990"/> but users reported on [[Bulletin board system|BBS]] that they could run DOS/V on [[IBM PC compatible|IBM PC clone]]s.<ref name="NBP_1991"/> The development team unofficially confirmed these comments, and modified incompatibilities of DOS/V. It was a secret inside the company because it would prevent sales of PS/55 and meet with opposition. Hatori said,<ref name="AsahiPC_19950401"/>

{{Blockquote|text=We hid the DOS/V run on other IBM compatible machines. The fact was that we developed it could run on [[Gateway, Inc.|Gateway]]'s and any machines, but we had to keep the secret, not to spread it, because there are lots of enemies inside the company. In short, it was a double-edged sword. If the DOS/V run on such cheap compatible machines, conversely the 5550 series which had taken high profit up may not be sold. In fact, 80% of staff in Yamato office opposed it.|sign=|source=}}

Maruyama and Mii had to convince IBM's branches to agree with the plan. In the beginning of December 1990, Maruyama went to IBM's Management Committee, and presented his plan "The low-end PC strategy in Japan". At the committee, a topic usually took 15 minutes, but his topic took an hour. The plan was finally approved by [[John Fellows Akers|John Akers]].<ref name="AsahiPC_19950401"/>

After the committee, Susumu Furukawa, a president of [[Microsoft Japan]], could make an appointment with IBM Japan to share the source code of DOS/V.<ref name="Furukawa_2015"/> On 20 December 1990, IBM Japan announced they founded OADG and Microsoft would supply DOS/V for other PC manufacturers. From 1992 to 1994, many Japanese manufacturers began selling IBM PC clones with DOS/V. Some global PC manufacturers entered into the Japanese market, [[Compaq]] in 1992 and [[Dell]] in 1993. [[Fujitsu]] released IBM PC clones (FMV series) in October 1993, and about 200,000 units were shipped in 1994.<ref name="NBP_19941010"/>

The initial goal of DOS/V was to enable Japanese software to run on laptop computers based on the IBM global standards rather than the domestic computer architecture. As of 1989, the VGA was not common, but they expected the LCD panels with VGA resolution would be affordable within a few years. The DOS/V lacked its software library, so IBM Japan requested third-party companies to port their software to the DOS/V. The PS/55 Model 5535-S was released as a laptop terminal for the corporate sector. They only had to supply a few major business software to the DOS/V.<ref name="TheBASIC_1993"/>

In March 1991, IBM Japan released the [[PS/55note]] Model 5523-S which was the lower-price laptop computer. It was a strategically important product to popularize the DOS/V into the consumer market, and led to the success of subsequent consumer products such as the [[ThinkPad]].<ref name="ThinkPad_2002"/> However, the DOS/V itself sold much better than the 5523S because advanced users purchased it to build a Japanese language environment on their IBM compatible PCs.<ref name="AsahiPC_19981101"/>

In 1992, IBM Japan released the PS/V (similar to the [[IBM PS/ValuePoint|PS/ValuePoint]]) and the [[ThinkPad]]. They were based upon an architecture closer to PC compatibles, and intended to compete with rivals in the consumer market. As of December 1992, the PS/V was the most selling DOS/V computer.<ref name="NBP_1993-03-01"/> In January 1993, NEC released a new generation of the PC-98 to take back its initiative. NEC advertised that the scrolling speed of the word processor [[Ichitaro (word processor)|Ichitaro]] on the PC-9801BX was faster than on the PS/V 2405-W.<ref name="NikkeiPC_19930315"/> Yuzuru Takemura {{Nihongo|2=竹村 譲}} of IBM Japan said, "Let us suppose the movement towards Windows is inevitability. Processors and graphics cards will become faster and faster. If the PC-98 holds its architecture, it never beat our machine at speed. Windows is developed for the PC/AT architecture. Kanji glyphs are also supplied as a software font. The only thing IBM have to do is tuning up it for the video card. On the different architecture, it will be hard to tune up Windows".<ref name="TheBASIC_1993"/>[[File:Microsoft Windows 3.1 Jpn box.jpg|thumb|Windows 3.1 for MS-DOS 5.0/V]]In 1993, Microsoft Japan released first retail versions of Windows ([[Windows 3.1x|Windows 3.1]]) for both DOS/V and PC-98. The DOS/V contributed the dawn of IBM PC clones in Japan, yet PC-98 had kept 50% of market share until 1996.<ref name="NSS_19970424"/> It was turned round by the release of [[Windows 95]].