National FS-4000
This page was last modified 16:22, 3 November 2021 by Mars2000you. Based on work by Rderooy and Gdx.




The National FS-4000 is a "Word-pro Persocom" (Word processor Personal Computer) with a built-in 24 dots thermal transfer printer. The FS-4000 was available in full black or in black and white. It is the last MSX1 computer released by National and was aimed at the Japanese market.

This firmware is automatically launched when you boot the machine, there is no way to bypass it. Two switches at the back allow to change the print density and select an external printer instead of the built-in printer. On emulators, these switches are not yet emulated.

The original replacement ink cartridge is the CF-PR120, but you can also use the CF-PR110.

Brand National
Model FS-4000
Year 1985
Region Japan
Launch price ¥106,000
RAM 64kB in slot 3-2, 2kB SRAM for printer handling
Media MSX Cartridges
Video Texas Instruments TMS9128
Audio PSG (YM2149 integrated in MSX-Engine S3527)
Chipset Yamaha S3527
Keyboard layout QWERTY/JP50on + numeric keypad
Extras built-in printer, switch for selecting print density, switch for selecting an external printer, Kanji-ROM level 1, firmware: Japanese + English Word Processor, specific compound Kanji dictionary (not MSX-JE), kanji driver
Emulation ROMs dumped and emulated with exception of the internal printer. The printer select switch is set to External printer and cannot be changed.


This computer comes with a built-in Japanese/English Word Processor with kana-kanji conversion, however the procedure is not compatible with MSX-JE.

The firmware menu presents 3 options:

  1. Japanese Word Processor (15 characters per line)
  2. English Word Processor (30 characters per line)

Each Word Processor has a sub-menu with 5 options: 1 - New text - 2 - Edit text - 3 - Print - 4 - Save - 5 - Load. In options 1 and 2, you can access the settings with F8.

Only 2 paper sizes are available for the printer: A4 and B5. Saving of text and settings can only be done to tape.

The Kanji-ROM Level 1 (JIS1) contains 3509 characters and the Kanji dictionary is very rudimentary. To get a better kana-kanji conversion, it's recommended to use the FS-SR022 Kanji Dictionary Tool cartridge with the FS-4000 computer.

From MSX-BASIC, you can go back to the word processors with CALL JWP or _JWP for the Japanese Word Processor and CALL EWP or _EWP for the English Word Processor. 50



National FS-4000 (black/white)
National FS-4000 back connectors
National FS-4000 right side
National FS-4000 manuals (+ National CF-2506 RF converter, cables and Panasonic FS-JS220 joypad)
National FS-4000 inside
National FS-4000 PCB
National FS-4000 (black)
National FS-4000 box


National FS-4000 Main menu
National FS-4000 Japanese Word Processor sub-menu
National FS-4000 Japanese Word Processor option 3 of sub-menu
National FS-4000 Japanese Word Processor option 4 of sub-menu
National FS-4000 English Word Processor settings
National FS-4000 English Word Processor option 3 of sub-menu


The National FS-4000 is a MSX1 with 2 cartridge slots (in parallel one at the top). The CPU is a Z80 from NEC (D780C-1). There is also a co-processor (NEC D7807G) with 2kB of SRAM for the printer handling. The MSX-Engine comes from Yamaha (S3527).

Slot Map

Slot 0 Slot 1 Slot 2 Slot 3-0 Slot 3-1 Slot 3-2 Slot 3-3
Page C000h~FFFFh Cartridge
Slot 1
Slot 2
Page 8000h~BFFFh Kanji
Page 4000h~7FFFh Main-ROM MSX
Page 0000h~3FFFh



As designed, the built-in word processor cannot save to disk. In fact adding a disk drive has the effect that the built-in software is skipped, making the integrated word processor inaccessible. No work around is available other then booting while keeping the SHIFT key pressed to disable the disk drive.

External Links