Panasonic FS-A1WSX
This page was last modified 19:04, 26 May 2023 by Mars2000you. Based on work by Gdx and Grauw and others.




The FS-A1WSX is a computer released on the Japanese market by Panasonic. It was the successor of the FS-A1WX and incorporated a few changes :

  • the Data Recorder connector is replaced by a S-Video output
  • the cassette port on this machine is combined with the RGB connector, it is possible to load/save via this connector, but the volume is very low by comparison with the normal tape interface

A Ren-Sha Turbo feature provides auto-fire mode while playing games. The repetition speed can be adjusted with a slider.

This model was available in black.

Brand Panasonic
Model FS-A1WSX
Year 1989-10
Region Japan
Launch price ¥69.800
RAM 64kB in slot 3-0 + 16kB SRAM
VRAM 128kB
Media MSX cartridges, 720kB 3,5" floppy disks
Video Yamaha V9958
Chipset Toshiba T9769 model B or C and gate array Mitsubishi M50014
Keyboard layout QWERTY/JIS + numeric keypad
Extras CPU Turbo mode, 720kB 3,5" floppy disk drive, firmware switch, pause button, Ren-Sha Turbo slider (autofire), Kanji-ROM level 1 & 2, Kanji BASIC, MSX-MUSIC BASIC, firmware (A1 Cockpit, Word Processor with support for color printers, MSX-JE), system disk for option 3 of firmware, utility disk with MSX-DOS 1 and tools
Emulation ROMs dumped and emulated. The firmware switch is emulated in the OFF position, such that the machine will not by default boot to the integrated firmware application. This can be changed in openMSX with the "set firmwareswitch on" command.


The firmware is launched automatically when you boot the machine. Bypassing this software on startup requires the user to change the position of the front switch before booting the computer. Contrary to the previous Panasonic MSX2 and MSX2+ machines, the DEL key no longer disables the built-in firmware application while booting.

By comparison with the FS-A1WX, the built-in Cockpit software is very similar, but has color printer support. The design of the main menu and the other options has been revisited, the music of the Cockpit is no longer deafening.

The firmware menu includes 10 options:

  • 1 - Japanese Word Processor
  • 2 - Beginner Word Processor
  • 3 - Word Processor Lessons (requires the System disk)
  • 4 - Address Book
  • 5 - Business Card
  • 6 - AV Labels (Video - Cassette - Diskette)
  • 7 - AV Labels (Custom)
  • 8 - Accessories (Calculator, Calendar and Clock Settings)
  • 9 - Mouse and Printer Settings
  • 0 - MSX-BASIC

From MSX-BASIC, you can go to the firmware menu with CALL MENU or _MENU.

Floppy disks

Two floppy disks were provided with this computer:

  • the first disk is a System disk, required to use option 3 of the firmware
  • the second disk is an Utility disk that contains MSX-DOS 1 and has its own menu:
    • 1 - Disk Utility
    • 2 - Video Graphics (in screen 8)
    • 3 - Color Printer Tool
    • 4 - MSX-BASIC

The Video Graphics application in screen 8 is a version without superimposing and digitizing support, but there's an icon for using the FS-RS500 scanner.

Option 3 is designed for the Panasonic FS-PC1 color printer.

When you close one of these applications, you go back to the MSX-DOS command line. You can then enter TOOL to relaunch the menu of the Utility disk.

To run MSX-DOS, choose option 4 in the menu to go to BASIC, then enter CALL SYSTEM. You can also press CTRL+STOP when booting with the disk in drive A, this to avoid the launching of the Tools menu.



Panasonic FS-A1WSX box and computer
Panasonic FS-A1WSX
Panasonic FS-A1WSX box
Panasonic FS-A1WSX left side
Panasonic FS-A1WSX right side
Panasonic FS-A1WSX manuals
Panasonic FS-A1WSX label
FS-A1WSX floppy disks
Panasonic FS-A1WSX
FS-A1WSX PCB underside
EME213MA drive belt swap
EME213MA disk drive
EME213MA alignment sensor - must be moved during beltswap
Panasonic FS-A1WSX back


Cockpit menu
Cockpit Japanese Word Processor
Cockpit Beginner Word Processor
Cockpit Word Processor Lessons
Cockpit Address Book
Cockpit Business Card
Cockpit AV Labels sub-menu
Cockpit AV Labels - Video
Cockpit AV Labels - Cassette
Cockpit AV Labels - Diskette
Cockpit Custom AV Labels sub-menu
Cockpit New Custom AV Label
Cockpit Accessories sub-menu
Cockpit Accessories - Calculator
Cockpit Accessories - Calendar
Cockpit Accessories - Clock Settings
Cockpit Mouse and Printer Settings

Utility disk

Cockpit - Utility disk - menu
Cockpit Disk Utility
Cockpit Video Graphics
Cockpit Color Printer Tool
Cockpit Color Printer Tool
Cockpit Color Printer Tool


The FS-A1WSX is a MSX2+ with 2 cartridge slots (one at the top, one at the back) and a Z80A integrated in MSX-Engine T9769(A or B) from Toshiba. This Z80A can be switched from to 3.58 MHz to 5.37 MHz via I/O ports. The floppy disk controller is the Toshiba TC8566AF.

There is a front switch to disable the firmware execution on startup.

This model supports up to 256 kB of RAM after doing a little soldering. 512 kB is also possible with a more complicated modification. (See below)

The Panasonic FS-PC1 printer is required to print in color.

Floppy Disk Belt specifications:

Type: Rubber Belt
Thickness: 0.3mm
Diameter: 58mm
Width: 3mm

Slot Map

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 Cartridge
Slot 1
Slot 2
Page 8000h~BFFFh Kanji
Page 4000h~7FFFh Main-ROM MSX-Music Disk ROM
Page 0000h~3FFFh Sub-ROM
  • Slot 3-3 is divided into 8kB Pages using the Panasonic mapper. Each can contain internal RAM, ROM or SRAM. A1 Cockpit runs in this slot.


CPU Turbo mode

Contrary to Sony and Sanyo MSX2+ systems which run only at 3.58 MHz, the Panasonic systems are capable of running at 5.37 MHz. In Basic this can be achieved with the following commands:

Activating the 5.37 MHz Mode

Switching to Turbo 5.37 MHz mode can be activated with this command:

OUT 64,8: OUT 65,0

Prefer to use the following line in your program:

IF PEEK(&H2D)=2 THEN OUT 64,8:IF INP(64)=247 THEN IF (INP(65) AND 4)=0 THEN OUT 65,0

Deactivating the 5.37 MHz Mode

Switching back to 3.58 MHz is done with this command:

OUT 64,8: OUT 65,1

Prefer to use the following line in your program:

IF PEEK(&H2D)=2 THEN OUT 64,8:IF INP(64)=247 THEN IF (INP(65) AND 4)=0 THEN OUT 65,1

Maintenance / Repair / Upgrades

Recommended batteries: Lithium batteries or Eneloop (white or cyan).
Batteries advised against: Alkaline batteries because they leak one day or another.