Panasonic FS-A1WSX
This page was last modified 10:29, 22 September 2018 by Gdx. Based on work by Rderooy and Mars2000you 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. Official price: ¥69,800

Brand Panasonic
Year 10-1989
RAM 64kB in slot 3-0
VRAM 128kB
Media MSX cartridges, 720kB 3,5" floppy disks
Video Yamaha V9958
Chipset Toshiba T9769 model B or C
Extras MSX-JE, Ren-Sha Turbo (autofire), hardware pause key, MSX-MUSIC BASIC, Kanji-ROM level 1 & 2, firmware (A1 Cockpit, Word Processor with support for color printers, etc), firmware switch, Z80 compatible CPU built in MSX Engine (T9769x) that can be switched to from 3.57 MHz to 5.37 MHz via I/O port, 2DD floppy disk drive, 16kB SRAM, Kanji BASIC


This machine has an improved A1 Cockpit software with color printer support, especially useful for the provided Word Processor.

By comparison with the FS-A1WX, the built-in Cockpit software is very similar, including the Word Processor where one of the options requires the first system disk with the MSX-JE input system for the kana-kanji conversion. The design of the main menu and the other options has been revisited, the music of the cockpit is no longer deafening. On the second system disk, the picture gallery has been replaced by a tool for the Panasonic FS-PC1 color printer.

Contrary to the previous Panasonic MSX2 and MSX2+ machines, the DEL key no longer disables the built-in firmware application while booting : the firmware can be skipped only by changing the position of the front switch before booting the computer. From MSX-BASIC, you can go to the firmware menu with CALL MENU or _ MENU. When you quit an application of the second system disk, you come on the MSX-DOS command line; by entering TOOL on this command line, you can go back to the menu of this system disk.


Panasonic FS-A1WSX
Panasonic FS-A1WSX rear
Panasonic FS-A1WSX leftside
FS-A1WSX manuals
FS-A1WSX box
EME213MA Disk Drive
EME213MA Drive belt swap
EME213MA Alignment sensor - must be moved during beltswap


The FS-A1WSX is a MSX2+ with 2 cartridge slots (one at the top, one at the back) and a Z80A integrated in the MSX-Engine T9769(B or C) from Toshiba. This Z80A can be switched from to 3.57MHz to 5.37MHz via I/O port. There is a front switch to eventually skip the firmware execution. Floppy Disk Controller chip is the TC8566AF.

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
Bank C000h~FFFFh Cartridge
Slot 1
Slot 2
Bank 8000h~BFFFh Kanji
Bank 4000h~7FFFh Main-ROM MSX-Music Disk ROM
Bank 0000h~3FFFh Sub-ROM
  • Slot 3-3 is also divided into 8kB banks. Each can contain internal RAM, ROM or SRAM using the Panasonic_mapper.


CPU Turbo mode

Contrary to Sony and Sanyo MSX2+ systems which run only at 3.57 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 the following command:

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

Deactivating the 5.37 MHz Mode

Switching back to 3.57 Mhz is done with this command:

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