Sony HBM-512
This page was last modified 21:16, 12 December 2018 by Msxholder. Based on work by Robosoft and Gdx and others.

The Sony HBM-512 memory mapper is one of the few memorymappers made by an original MSX manufacturer and runs on any MSX2 computer. It was originally designed for the Sony HB-G900P videocomputer and doesn't work on computers that run on a higher clockfrequency than 3.58MHz, because of the slow RAM chips.

This cartridge is intended to be expandable to 1024kB.



The pcb shown in the picture is not from the HBM-512: its a clone for an philips case !

Sony HBM-512 cartridge front
Sony HBM-512 cartridge back
Sony HBM-512 PCB
Sony HBM-512 box
Sony HBM-512 Manual front
Sony HBM-512 Manual back

Minimum System Requirements

  • MSX2 computer, one free slot cartridge

Note: As all standard Memory Mapper, this cartridge is not supported by MSX1 computers except with Nextor or a MSX-DOS2 unbridled (like Sunrise CF interface). On MSX1 without Nextor, we need to manually initialize pages order of the mapper from basic before it can be used.


  • CHKMEM.BIN (Utility that displays the slot of RAM, Memory Mapper and MegaRAM by LARK)
  • Mapper Info (by Yukke)
  • MEGA16.COM (loader for megaroms with 16k mapper)
  • MEMTEST.COM (RAM of Memory Mapper tester by Masatoshi Fujimoto)
  • TESTMAP.COM (RAM of Memory Mapper tester by Marteen)
  • SofaRom (MegaRoms and Roms loader by Louthrax)