> In the west, you'd buy a PC (or a home computer) to play games, edit documents or manage your business. The latter two were pretty much impossible in Japan, as the computers of that era couldn't handle the complexities of the Japanese language and character set.
NEC sold a Kanji board for their Z80-based PC8801 mk II (released 1983). The original 1979 PC8801 didn’t have an official Kanji board from NEC, but one was available for it from a third party vendor. With a Kanji board, you could do Japanese word processing. I believe the same was true of many other 8-bit vendors.
Inevitably the greater complexity of Kanji required more advanced hardware, so Kanji-capable machines usable for business and education were initially more expensive than games-only machines that lacked it. But in 1990 IBM released DOS/V, which demonstrated that standard PC hardware had become powerful enough to support Kanji without needing any dedicated circuitry. And even before that, I believe already by the late 1980s many machines (such as NEC PC-9800s) were coming with Kanji support as a standard feature rather than an optional add-on card.
There was this entire Japanese subculture of microcomputers/home computers/PCs. Machines like NEC PCs you mentioned, proprietary models from Fujitsu and others, the many incarnations of MSX (which I think might have started out as a Microsoft initiative?), and of course the nowadays legendary Sharp X68000, that were marketed and sold in Japan but not necessarily well known - or even available - outside of east and south-east Asia (though I think MSX also got some traction in South America).
The MSX standard was originally developed in Japan, with the cooperation of Microsoft in the US-its OS was a port of MS-DOS to 8-bit Z80 systems, Tim Paterson the original developer of MS-DOS did the port-he’d left Microsoft by this point to found his own company, so he did it at his new company under contract to Microsoft. MSX systems
were also quite popular in Europe-Phillips was also a major manufacturer of them. Like other 8-bit machines, you could get an add-on board or cartridge to add Kanji support. First generation MSX machines, some higher-end models had Kanji built-in, lower-end models you needed to buy the expansion. Later generations of Japanese MSX machines, Kanji support was standard even on the entry models. Machines were also differentiated by how many Kanji they supported (JIS1 provided the ~3000 most commonly used Kanji, JIS2 added another ~1000 which were less commonly used).
There were other Japanese machines which found a foothold in some overseas markets. IBM Japan developed a modified version of the PCjr, the PC JX, for the Japanese market. IBM ended up also selling the JX to schools in Australia and New Zealand (minus the Kanji circuitry), and many bought them (I remember using one at school when I was 9 or 10.)
Similarly, Fujitsu’s cloned IBM mainframes, the FACOM machines, were popular with Australian businesses and governments in the 1980s and first half of the 1990s. They were also sold in other markets, but in other markets were generally rebadged (or even manufactured under license) by vendors such as Amdahl in the US and Siemens in Europe, whereas in Australia they were sold directly by Fujitsu and generally closer to what was sold in Japan.
That powerful IBM system was unique to other systems being brought into Japan, in that IBM started up that business just before the rule that required a Japanese partner. So it didn't really get shared like other technologies that lead to most other Japanese tech giants.
DOS/V was just PC-DOS with some additional device drivers. IBM licensed it to Microsoft who in turn licensed it to other vendors such as Toshiba, Sharp, AST, Compaq, Dell and Fujitsu.
The biggest barrier to its adoption was vendors such as NEC (with their PC9800 series) and the AX consortium (Oki, Casio, Canon, Sanyo, Sharp, Hitachi, Mitsubishi) who had already invested in proprietary hardware for Kanji support and were threatened by the support of Japanese text on global standard hardware. (That said, some AX vendors decided to embrace DOS/V anyway, such as Sharp.)
Another barrier was that DOS/V had different APIs from those previous solutions so you needed new software that could support it.
NEC sold a Kanji board for their Z80-based PC8801 mk II (released 1983). The original 1979 PC8801 didn’t have an official Kanji board from NEC, but one was available for it from a third party vendor. With a Kanji board, you could do Japanese word processing. I believe the same was true of many other 8-bit vendors.
Inevitably the greater complexity of Kanji required more advanced hardware, so Kanji-capable machines usable for business and education were initially more expensive than games-only machines that lacked it. But in 1990 IBM released DOS/V, which demonstrated that standard PC hardware had become powerful enough to support Kanji without needing any dedicated circuitry. And even before that, I believe already by the late 1980s many machines (such as NEC PC-9800s) were coming with Kanji support as a standard feature rather than an optional add-on card.