National CF-2131
This page was last modified 20:55, 7 October 2021 by Mars2000you. Based on work by Gdx and Rderooy.


The cartridge CF-2131 is an expansion of 16kB RAM made and sold by National in Japan.

Its RAM is placed on page 2 (8000h~BFFFh). As such it is only useful to upgrade a 16kB MSX to 32kB. However the systems base memory and the expansion will be in different slots which can cause compatibility problems with some software that blindly assumes all memory to be in a single slot.

If you are looking for a memory expansion we recommend to buy another standard expansion. A 64kB RAM expansion, or even better a Memory Mapper cartridge that initializes its segments itself at start up is the best choice.


National CF-2131 box
National CF-2131
National CF-2131
National CF-2131 PCB
CF-2131 underside
National CF-2131 box and content

Minimum System Requirements

  • MSX1 computer with 16kB RAM, one free slot cartridge