National FS-5500F2
This page was last modified 21:48, 1 February 2022 by Mars2000you. Based on work by Grauw and Rderooy and others.




The National FS-5500F2 is a MSX2 computer with superimpose and digitize capabilities. It was aimed at the Japanese market. The machine is basically identical to the FS-5500F1. The only difference is that this one has two floppy disk drives.

As for the Philips NMS 8250 and NMS 8255 machines, the correct name of the computer appears only at the back while 'National FS-5500' is displayed on front.

Two switches on the back allow a selection between JP50on or JIS keyboard layout and to enable/disable the built-in firmware, related to the control of an external device for superimposing and digitizing operations.

This computer has a very extended audio/video editing control panel and a built-in trackball (renamed 'Ball Mouse'). The keyboard has an extra key called 'AVC' (Audio Video Control) that can be combined with the SELECT, INS, DEL and function keys.

Firmware data can be saved on the FS-CR1008S cartridge. It contains 8kB SRAM and a battery to preserve them when the computer is off. This professional computer has three expansions slots that can be used to increase the RAM.

Brand National
Model FS-5500F2
Year 1985-12-21
Region Japan
Launch price ¥228,000
RAM 64kB in slot 3-2
VRAM 128kB
Media MSX cartridges, 2DD floppy disks
Video Yamaha V9938
Audio PSG
Chipset Yamaha S3527
Keyboard layout QWERTY/JP50on by default (JIS available with switch) + numeric keypad
Extras Two 720kB 3,5" floppy disk drives, separate keyboard with trackball, reset button, eject button for each cartridge slot, switch for choosing keyboard layout, switch for enabling/disabling the firmware, audio/video editing control panel, headphone jack with volume controller at front, backup of the clockchip data, Kanji-ROM level 1, MSX-DOS 1 + Video Graphics (on disk), firmware with National BASIC
Emulation ROMs dumped and emulated with exception of the superimpose functionality and the 3 special expansion slots in the back which need validation. The firmware application switch is emulated in the OFF position. Keyboard switch is set to JIS and cannot be changed.


Accurate infos about the built-in firmware are missing, but it seems to be designed for the control of external devices during superimposing and digitizing operations, as the computer has two unusual connectors: alarm output terminal and system terminal (control output).

This firmware adds 3 instructions to MSX-BASIC: see National BASIC.


Besides MSX-DOS 1, the provided floppy disk contains Video Graphics, a graphic tool with superimposing and digitizing options and mouse support in screen 8.

MSX-DOS can't be launched from this disk as pressing CTRL+STOP when booting leads to a frozen screen. Inserting the disk after booting and entering POKE &HF346,1: CALL SYSTEM leads to the graphic tool. The only remaining option is to copy MSXDOS.SYS and COMMAND.COM to a new formatted disk with the MSX-BASIC COPY command.



National FS-5500F2
National FS-5500F2 front
National FS-5500F2 back
National FS-5500 keyboard
National FS-5500F2
National FS-5500 control panel
National FS-5500 manuals + disk
FS-5500 floppy disk
National FS-5500 PCB
FS-5000/5500 Expansion Slots PCB
National FS-5500 manuals
National FS-5500 Video Board
National FS-5500 RAM + ROM Board


National FS-5500 Video Graphics - intro screen
National FS-5500 Video Graphics - main menu
National FS-5500 Video Graphics - video effects


The National FS-5500F2 is a MSX2 with 2 cartridge slots and two 3.5" disk drives on the front. The CPU is a Z80 from NEC (D780C-1). The MSX-Engine comes from Yamaha (S3527). The floppy disk controller is the MB8877A from Fujitsu Microelectronics.

The three slots in the back have the same pinout as standard extension slot but the connector is different.

Slot Map

Note: The location of the three expansion slots has been checked on a real machine.

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


  • RF output with channel selector switch
  • RGB21 output (not Scart)
  • RCA audio and video input
  • RCA audio and video output
  • Keyboard connector
  • Headphone jack (3.5mm?)
  • Alarm output terminal
  • System terminal (control output)
  • Centronics compatible Parallel port for a printer
  • Data Recorder connector
  • 2 general connectors (Joysticks, Mouse, Paddle controlers, etc)
  • 2 cartridge slots at front
  • 3 expansion slots on the back
  • Power plug for main power supply (JIS C 8303 class, AC 100V +/-10% 50/60Hz)
  • 2 power outlets for monitor (AC 100V)
  • Floating ground