Casio MX-101
This page was last modified 14:13, 26 February 2018 by Rderooy. Based on work by Mars2000you and Wernerkai and others.



The MX-101 is the same computer as the Casio MX-10 but with added antennas. It allows to display the image on the TV screen by UHF signal without cable. The standard cable is also usable.

The other characteristivs of this computer are identic to the MSX-10: the quality of the rubber keyboard is dubious and the tape interface is out of the machine, what means a non-standard tape connector that requires the FA-32 CMT I/F package as adapter.

Joypad keys are arranged in a diamond-shape (instead of a circle) without the 'Joypad 1' indication. Together with the TR1 and TR2 keys on the bottom left of the computer, these are equivalent to a joystick inserted into joystick port 1. Probably, only the games that use the BIOS routines to handle the joysticks are supported by these internal joypad, it includes the BASIC games using the STICK command. (need confirmation about it)

Apart from the 'Joypad 1' keys, the computer also features normal cursor keys aligned above the joypad keys.

It's possible to add two cartridge slots and the printer port by combining this computer with the expansion unit KB-10. The power supply is not internal, the provided AC power adaptor (AD-4175) is required if you don't use the KB-10 unit, which has its own power supply.

This machine was aimed at the Japanese market and available only in black.

Official price: ¥19,800 for the computer, ¥13,800 for the expansion unit and ¥3,000 for the tape connector adapter.

Brand Casio
Type MX-101
Year 1987
RAM 16kB in slot 0 (with or without KB-10)
Media MSX cartridges
Video Texas Instruments TMS9118NL
Audio PSG (AY-3-8910 in MSX Engine)
Chipset Hitachi HD62003
Extras Two specific keys TR1 and TR2, Joypad 1 cursors, wireless TV connection, (with KB-10) third cartridge slot


Casio MX-101 with left antenna
Casio MX-101 (without antenna)
Casio MX-101 with all its antennas
Casio MX-101 box
Casio MX-101 PCB
Casio MX-101 PCB Back
Casio MX-101 AC adaptor detail
Casio MX-101 box backside
Casio MX-101 left side


The Casio MX-101 is a MSX1 with a Z80A from Rohm (BU18400A-PS). The MSX Engine is an HD62003 from Hitachi.

The pins SW1, SW2, -12V and +12V of the cartridge connector are not connected. In general, MSXs without a protection switch have pins SW1 and SW2 connected to GND. A few rare cartridges use SW1 and SW2 as GND and some cartridges need the -/+12V as for example the FM-PAC.

The AC power adaptor ouput is 7V with minus at center, 800mA. It is not useful with the expansion unit.

Slot Map without KB-10

Slot 0 Slot 1 Slot 2 Slot 3
Bank C000h~FFFFh RAM Cartridge
Bank 8000h~BFFFh
Bank 4000h~7FFFh Main-ROM
Bank 0000h~3FFFh

Slot Map with KB-10

Slot 0 Slot 1 Slot 2 Slot 3
Bank C000h~FFFFh RAM Cartridge
Bank 8000h~BFFFh
Bank 4000h~7FFFh Main-ROM
Bank 0000h~3FFFh


  • RF output
  • Analog sound output (mono)
  • Composite video output
  • "UHF channel" connector for antenna (Wireless video signal)
  • MT/IF connector (requires CMT I/F package FA-32 as adapter to use a standard tape recorder)
  • Centronics compatible Parallel port for a printer (on the left side of the KB-10 expansion)
  • 2 general connectors (joysticks, mouse, paddle controllers, ...)
  • 1 cartridge slot (without KB-10) or 3 cartridge slots (with KB-10)
  • 1 expansion slot for KB-10 unit
  • AC power adaptor connector