|
The NEC V60 (μPD70616) was a CISC processor manufactured by NEC starting in 1986. The V60 was the first 32-bit general-purpose microprocessor commercially available in Japan.〔Ken Sakamura, "(Recent Trends )", IEEE Micro, April 1988, pp. 10-11〕 A relatively obscure design in the West, it was a radical departure from NEC's previous V-series CPUs—the NEC V20-V50 series—, which were based on the Intel x86 model,〔 although it retained the ability to emulate them. According to NEC's documentation, the architectural change was made due to the increasing demand and diversity of programs, calling for a processor with both power (the 32-bit internal bus) and flexibility, having large numbers of general-purpose registers—a common feature of RISC architectures and a benefit to the emerging high-level languages. The V60 architecture retained however CISC features (which its manual describe as mainframe-based) like variable-length instructions, memory-to-memory operations including string manipulation, and fairly complex operand addressing schemes.〔(NEC V60 Programmer's Reference Manual )〕 Although it had a 32-bit internal bus, the V60 had only a 16-bit external data bus and a 24-bit address bus. Its architecture was carried largely intact to the V70 (μPD70632) model, which had external 32-bit buses and was released in 1987.〔 Launched in 1989, the V80 (μPD70832) was the culmination of the series having on-chip caches, a branch predictor, and less reliance on microcode for complex operations.〔 The V60-V80 architecture did not enjoy much commercial success.〔 The operating systems developed for the V60-V80 series were generally oriented toward real-time operation. Having been used in some Japanese game arcade products, the V60 and V70 also survive in emulation software for this niche. == V60 == Work on the processor began in 1982 under the leadership of Yoichi Yano. About 250 engineers participated and the V60 (μPD70616) debuted in February 1986. It had a six-stage pipeline, built-in memory management unit and floating-point arithmetic. It was manufactured in 1.5 µm on a two-layer aluminum CMOS process using 375,000 transistors on a die.〔 It operated at 5 V and was initially packaged in a 68-pin PGA.〔Dataquest, "Japanese Semiconductor Industry Service", 1st Quarter 1987, p. 18 (pdf p. 182 in (this multi-volume archive ))〕 The first version ran at 16 MHz at attained 3.5 MIPS.〔 Its sample price at launch was set to ¥100,000 ($588.23). It entered full-scale production in August 1986.〔 Sega chose this processor for most of its arcade games in the 1990s; the Sega System 32 and Sega Model 1 architectures both used this as their main CPU. (The latter used the lower-cost μPD70615 variant, which doesn't implement V20/V30 emulation.〔) The V60 was also used as the main CPU in the SSV arcade architecture—so named because it was developed together by Seta, Sammy, and Visco. Sega originally considered using a 16-MHz V60 as the basis for its Sega Saturn console, but after receiving word of the Playstation's processor (R3000A at 33.8 MHz) instead chose the dual-SH-2 design for the eventual production model.〔(【引用サイトリンク】author=Richard Tan )〕 In 1988, NEC released a kit called ''PS98-145-HMW'' for Unix enthusiasts. The kit contained a V60 processor board that could be plugged into select models of the PC-9800 computer series and a 15-floppy disk distribution of their PC-UX/V release 2.0. The suggested retail price for this kit was 450,000 Yen.〔(型 名 ：PS98-145-HMW 品 名 ：PC-UX/V(Rel2.0)(V60) ), NEC product sheet〕 NEC themselves included a V60 processor in their 1991 Bungo mini 5SX, 7SX, and 7SD word processor computers, where the V60 was used as fast outline font processor, while the main system processor was a 16 MHz NEC V33.〔(Bungo mini 5SX, Bungo mini 7SX, Bungo mini 7SD )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「NEC V60」の詳細全文を読む スポンサード リンク
|