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M > MATSUSHITA  > National JR 300   

National JR 300

The successor of the JR 200. Almost everything was changed, the computer has two CPUs to keep the compatibility with the previous models (JR-200). This machine has also a superimposition feature.

In fact it seems to be a mix between a JR-200 and a Sharp X1 system... quite strange ! But apparently this model was never really marketed.

A handheld model called JR 800 was launched few time later, but it was not compatible with the previous JR computers.

We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.
Please consider donating your old computer / videogame system to or one of our partners from anywhere in the world (Europe, America, Asia, etc.).


Doraemon was made by Matsushita too

Sunday 30th April 2023
Jaume De La Vega (España)


NAME  National JR 300
TYPE  Home Computer
YEAR  1984
BUILT IN LANGUAGE  JR Basic 5.0 and Extended Basic
KEYBOARD  Full stroke keyboard, 98 keys, 6 function keys, separated numeric keypad
CPU  Zilog Z80A + MN1800A (6802 compatible)
SPEED  4 Mhz (Z80A)
CO-PROCESSOR  MN1544 and MN1542
RAM  82 kb
VRAM  52 kb
ROM  40 kb (Basic : 16k)
TEXT MODES  80 x 25 / 40 x 25 / 32 x 24
GRAPHIC MODES  640 x 200 / 320 x 200 / 640 x 400
SOUND  3 channels, 8 octaves (Yamaha 8910)
SIZE / WEIGHT  Keyboard : 390 × 198 × 38 mm / 1.6kg
Main unit : 390 × 350 × 80 mm / 4.8 Kg
I/O PORTS  RGB video output, Monitor, Audio out, Expansion, Tape (600/2400 bauds), Centronics, Joysticks,
PERIPHERALS  JR-F01 5''1/4 disk units, JR-F02 additional disk-drive, JR-F03 3''1/2 disk-drives, JR-F04 additional 3''1/2 diks-drive, JR-P01 Graphic printer, RQ-8300 & RQ-8200 tape-recorders
PRICE  159000 yens

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Ready prompt
ZX Spectrum
Arcade cherry
Spiral program
Atari joystick
Battle Zone
Vectrex ship
C64 maze generator
Moon Lander
Competition Pro Joystick
Atari ST bombs
Elite spaceship t-shirt
Commodore 64 prompt
Pak Pak Monster
Pixel Deer
BASIC code
Shooting gallery
3D Cubes
Pixel adventure
Vector ship

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