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SPECIAL FEATURE: Microprocessors in Japan -- Status in 1978

IP.com Disclosure Number: IPCOM000131395D
Original Publication Date: 1979-May-01
Included in the Prior Art Database: 2005-Nov-10
Document File: 6 page(s) / 26K

Publishing Venue

Software Patent Institute

Related People

Ryoichi Mori: AUTHOR [+6]

Abstract

[Figure containing following caption omitted: By the third quarter of 1978, ten Japanese companies were producing some 80 types of microprocessors, including 61 original products. Both the rate of new product introductions and the directions of these developments are impressive.] As of mid-1978, Japanese microprocessors included many original products, such as 4-bit microcontrollers (most of which are single-chip microcomputers) and high-performance, general-purpose microprocessors (both 12- and 16-bit). The industry

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THIS DOCUMENT IS AN APPROXIMATE REPRESENTATION OF THE ORIGINAL.

This record contains textual material that is copyright ©; 1979 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Contact the IEEE Computer Society http://www.computer.org/ (714-821-8380) for copies of the complete work that was the source of this textual material and for all use beyond that as a record from the SPI Database.

SPECIAL FEATURE: Microprocessors in Japan -- Status in 1978

Ryoichi Mori

University of Tsukuba

Morihiko Tajima , Yoshikuni Okada , Hiroaki Tajima

Electrotechnical Laboratory, Tokyo

(Image Omitted: By the third quarter of 1978, ten Japanese companies were producing some 80 types of microprocessors, including 61 original products. Both the rate of new product introductions and the directions of these developments are impressive.)

As of mid-1978, Japanese microprocessors included many original products, such as 4-bit microcontrollers (most of which are single-chip microcomputers) and high-performance, general-purpose microprocessors (both 12- and 16-bit). The industry

was also second-sourcing several widely used chips, such as the Intel 8080A and the Motorola 6800 family. Since an earlier papers by the same authors surveys microprocessors in Japan through the second quarter 1977, this discussion is focused mainly on more recent products.

Four- and 8-bit original microprocessors

Table 1 lists original 4- and 8-bit microprocessors made in Japan; most are single-chip microcomputers. Among these, three chips illustrate the directions of product development: SM- 4, a very early single-chip microcomputer; M58840, the first microcomputer containing an A-D converter; and pCOM-83, a multiprocessor-oriented, single-chip microcomputer.

The SM-4 was the first CMOS single-chip microcomputer in Japan. The chip has two stages of four 9-bit shift registers and a 15-bit frequency divider. Figure 1 shows the architecture. HI to H3 can take three values: GND, Vm, and Vat, which can be used to drive liquid-crystal displays. Edith its very low power consumption, the SM-4 is suitable for applications which require a combination of precise timing and battery operation.

Mitsubishi has developed a new single-chip microcomputer, the M58840, which features analog input ports. In Figure 2, 2K of 8-bit ROM and 128 words of 4-bit RAM are shown on the devices The 42-pin DIP is made by a P-channel, aluminum-gate EDMOS process. Its 15 analog input ports can be directly connected to touchkey interfaces and various sensors (temperature, humidity, pressure, velocity, etc.).

(Image Omitted: Figure 1. The Sharp SM 4 chip has two stages of 9 bit shift registers and a 1 5- bit frequency divider. Three values of H (GND, Vm, and Vd) are suitable for driving liquid crystal displays.)

The on-chip A-D converter consists of a bit-select register, C; reference-voltage registers H-L; a D-A converter; the 15-port input register J. and 15 comparators (Figure 31. Th...