Panasonic FS-A1F
This page was last modified 19:42, 26 May 2023 by Mars2000you. Based on work by Gdx and B squared and others.




The Panasonic FS-A1F MSX2 is basically a FS-A1mkII with a built-in 3.5" floppy disk drive mounted on the front of the case, below the keyboard. The FS-A1F was available in black. It was aimed at the Japanese market.

This model has also been released by Kawai under the name KMC-5000.

Brand Panasonic
Model FS-A1F
Year 1987
Region Japan
Launch price ¥54.800
RAM 64kB in slot 3-0
VRAM 128kB
Media MSX cartridges, 2DD floppy disks
Video Yamaha V9938
Audio PSG (integrated in MSX-Engine S1985)
Chipset Yamaha S1985
Keyboard layout QWERTY/JIS + numeric keypad
Extras 720kB 3,5" floppy disk drive, pause button, reset button, Kanji-ROM level 1, Kanji driver ROM, DESKPAC firmware, Utility disk with MSX-DOS 1 and files used by the firmware
Emulation ROMs dumped and emulated


The firmware is launched automatically when you boot the machine. Bypassing this software on startup requires the user to press the DEL key during boot until a Beep sound.

It can be also bypassed by software. For example, if you make a cartridge that requires disks, just write 023h in RAM at address 0C3CEh to avoid the Deskpac execution.

The built-in firmware is a new version of the well-known Panasonic DESKPAC software. It presents 8 options:

  • 1 - Clock
  • 2 - Calendar
  • 3 - Calculator
  • 4 - Disk Utility
  • 5 - Word Processor, Address Book & Business Card
  • 6 - Video Graphics (in screen 8)
  • 7 - MSX-BASIC
  • 8 - Screen Colors

Besides, icons give access to Clock Settings and Screen Adjust. The icons of options 4 to 6 can be replaced by the Japanese name of the corresponding application when you click on the left bottom rectangle (it acts like a toggle).

Options 4 to 6 require the utility disk in drive A. 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 5 leads to 5 sub-options:

  • 1 - Word Processor (creating)
  • 2 - Word Processor (editing)
  • 3 - Business Card
  • 4 - Adddress Book
  • 5 - Cassette Label

Note: If you click on the screen in specific places with the mouse cursor, a hidden message is displayed. There are 5 hidden messages:

  • Hello!!
  • Produced by GOD ROOM
  • ナンカまちがっちゃたみたいネ (Looks like you got wrong)
  • ジョウダンはやめて (Stop joking!)
  • アレッ!みつかっちゃた (Uh? You found it)


An utility disk was provided with this computer.

Besides MSX-DOS 1, the disk includes several files that are useful with the firmware, optionally combined with the Panasonic FS-PW1 printer.



Panasonic FS-A1F manuals, floppy disk and RF converter
Panasonic FS-A1F
Panasonic FS-A1F box
Panasonic FS-A1F back
Panasonic FS-A1F right side
FS-A1F battery location
Panasonic FS-A1F label
Panasonic FS-A1F/FS-A1FM drive
FS-A1F main PCB and disk drive
FS-A1F upgraded to 128kB PCB
FS-A1F/FS-A1FM drive PCB
Panasonic FS-A1F Utility disk


DESKPAC Clock Settings
DESKPAC Screen Adjust
DESKPAC Calendar
DESKPAC Calculator
Options with Japanese names
Hidden message 1
Hidden message 2
Hidden message 3
Hidden message 4
Hidden message 5

Utility disk

DESKPAC Disk Utility
WP, Address Book & Business Card
DESKPAC Word Processor (creating)
DESKPAC Word Processor (editing)
DESKPAC Business Card
DESKPAC Address Book
DESKPAC Cassette Label
DESKPAC Video Graphics


The Panasonic FS-A1F is a MSX2 with 2 cartridge slots (one at the top, one at the back), a Z80A from Zilog (Z08400-04PSC), an MSX-Engine S1985 from Yamaha and the gate array uPD65013GF375 from NEC. The floppy disk controller is the Toshiba TC8566F.

This model can be easily upgraded to 128kB RAM by adding MB81464-12 x2 and two ceramic capacitors of 100 nF (104).

Floppy Disk Belt specifications:

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

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 driver A1 Cockpit
Page 4000h~7FFFh Main-ROM Disk ROM
Page 0000h~3FFFh Sub-ROM


Maintenance / Repair / Upgrades

  • During a floppy drive belt swap, You must not unscrew the optical sensor from the drive... instead you must unsolder it from the FDD mainboard, and slip the belt over the optical sensor.
Panasonic FS-A1F Disk Drive Pins requiring unsoldering
Panasonic FS-A1F Disk Drive before Belt swap

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

External links