Matsushita JR series


The National JR series was a line of 8-bit personal computers developed by Matsushita Communication Industrial Co., Ltd., a division of Matsushita Electric Industrial. Based on the success of the Sharp MZ and NEC PC-8000 series, these computers aimed primarily at the home computer and educational markets during the early 1980s.
The JR series included four computer models: the JR-100, the JR-200, the JR-300 and the JR-800. All four were sold under Matsushita's 'National' brand; the JR-100 and JR-200U were also sold elsewhere as 'Panasonic'.
The JR series found a strong foothold in Japanese schools, particularly the JR-200, which became a standard machine for teaching programming in BASIC.

JR-100

The National JR-100 was released on November 21, 1981, with a price of 54,800 yen. It was the cheapest domestically produced personal computer at the time of its release.
Like the Hitachi Basic Master and Sharp MZ-80, it was a low-performance, low-priced personal computer offering basic semi-graphic character based graphics, a monochrome display, and minimal sound ability. The CPU was an 8-bit Panasonic MN1800A NMOS microprocessor running at a slow 0.89 MHz, and it came with 16 KB of RAM. Compared to the cheaper imported Sinclair ZX81, the larger RAM on the JR100 made it possible to create better programs.
The computer case is angular and cream-colored, measuring 296mm wide x 154mm deep x 45mm high, being extremely compact. The green keyboard was made of rubber due to its low price, and was mockingly called the "eraser keyboard". It had a shortcut key function, allowing users to enter commands in one go. There was no space bar at the bottom, and the right shift key was replaced with a space bar.
Specifications:
  • CPU: MN1800A
  • Clock speed: 890 kHz
  • RAM: 16-32 KB
  • ROM: 8 KB
  • Graphics: Monochrome; text characters; semi-graphic characters with pixel matrix
  • Sound: Internal speaker
  • Connections: Monitor, Expansion, Tape
  • OS: JR-BASIC 1.0

JR-200

The National JR-200 was released at the end of 1982 with a price of 79,800 yen. It was a higher-end model than the JR-100, but not compatible with this machine.
The JR-200 is made of silver grey plastic, and has a black matte area around the chiclet keyboard area. It used the same MN1800A CPU as the previous model, but added a second processor, the 4-bit MN1544CJR, which is used for I/O and contains 128 bytes of RAM plus four kilobytes of ROM.
The computer received favorable reviews on its launch. Creative Computing wrote ''"The Panasonic JR-200 is one of the nicest new computers to make the scene in some time."''

Specifications

  • CPU: MN1800A + MN1544
  • Clock speed: 890 kHz
  • RAM: 36 KB
  • ROM: 16 KB
  • Graphics: 8 colors ; ; text characters; semi-graphic characters with pixel matrix
  • Sound: 3 voices, 5 octaves, square wave. Generated by the MN1271 sound, I/O and timer chip.
  • Connections: Composite and RF video, expansion, tape, printer port, floppy drive, joystick
  • OS: JR-BASIC 5.0

International Variants

Versions of the JR-200 were developed for the North American and European markets and announced in January 1983:JR-200U: Designed for North American and European markets, with modified power supply and video output standards;JR-200UP: Included a built-in printer interface to meet business and educational needs.

JR-300

The National JR-300, released in 1984 with a price of 159,000 yen, was completely redesigned in comparison with the earlier JR-100 and JR-200 models. The JR-300 was a hybrid 8/16-bit machine, having a Zilog Z80A CPU as well as a second MN1800A CPU to allow backwards compatibility with the JR-200.
It was advertised as "PC & TV 300" and came standard with a genlock function. A dedicated display was available for this. The size and design are similar to the Matsushita MSX machines with separate keyboard.
The JR-300 was primarily delivered to schools as an educational computer, and only a very limited number of machines were released to the general public.

Specifications

  • CPU: MN1800A + Z80A
  • Clock speed: 4 MHz
  • RAM: 82 KB
  • ROM: 40 KB
  • Graphics: 8 colors;,,
  • Sound: Yamaha 8910
  • Connections: RGB, Composite and RF video, sound out, expansion, tape, printer port, floppy drive, joystick
  • OS: JR-BASIC 5.0, Extended Basic

JR-800

A handheld model called the National JR-800 was launched in 1983 with a price of 128,000 yen, but it was not compatible with the previous JR computers. It was based around a Hitachi HD63A01V CPU running at 4.9152 MHz, with 16 KB of RAM, and featured a pixel LCD screen.
It was a B5 sized handheld computer, powered by four AA batteries or an AC adapter. A dedicated portable printer, the JR-P20, was also released.

Specifications

  • CPU: HD63A01V
  • Clock speed: 4.9152 MHz
  • RAM: 16 KB
  • ROM: 16 KB
  • Graphics: monochrome LCD, characters; pixels
  • Connections: tape, RS-232, printer, sound
  • OS: BASIC

Character set

The table below shows the semigraphics character set available on the Matsushita JR series, as shown on the operations manual. Characters are rendered using modern equivalents, the exact hardware font it not simulated.
234589EF
00@P┌◯┘
1!1AQ♠▁▗▏
2“2BR♥▂▞▎
3#3CS♦▃▙▖
4$4DT♣▄▛▌
5%5EU⬣▅▎▊
6&6FV←▆▜▟
7'7GW↓▇▚▟
89IY→┤┼▊
A*:JZ?│▒▝
B+;K┐◝░◞
E.>N^█╳▀◜
F/?O_◢╱└╲