MSX Cartridge Shop MegaFlashROM SCC+ SD
This page was last modified 19:03, 30 September 2021 by ATroubleshooter. Based on work by Gdx and Mars2000you and others.



The MegaFlashROM SCC+ SD is a combo of MegaFlashROM SCC+ and a Flash card (Micro SD or Micro SDHC) interface. The last and current version of the MegaFlashROM has all of the previous versions (except the emulation of 4 ROMs in subslots) with additional one or two Micro SD card slots, 8 MB flash ROM instead of 1 MB and a Memory Mapper of 512kB (optional).

There are a few incompatibility cases, usually having to do with opfx(sd) misdetecting the mapper type, or the software not liking slot expansion etc.

The disks/partitions on Micro SD are formatted FAT12 or FAT16. These are controlled by Built-in Nextor (an improved MSX-DOS2). Disk partitions are supported by PC/Mac. The disk and partitions can be initialised from Basic. No floppy drive nor additional interface is required.

The cartridge contacts are gold plated (some batches are hard gold and others flash gold).

Price: About €90 or €120 + shipping costs


MegaFlashROM SCC+ SD packaging
MegaFlashROM SCC+ SD cartridge
MegaFlashROM SCC+ SD PCB bottom


  • Flash card: 1 or 2 slots compatible with micro SD and micro SDHC cards
    • Supports hot card swap
    • Uses Nextor as DOS (native FAT12/16 support)
    • Maximum partition size of 4GB
    • High speed transfer (read and write)
  • RAM: 512K (optional)
  • FlashROM: 8MB (64Mbits)
    • Fast Writing
    • 7MB used for emulation of the MegaFlashROM mappers
      • Mappers emulation: Plain 64K, ASCII 8/16K, Konami without SCC, Konami SCC+
      • ROM drive: You can install a DSK as ROM drive.
      • Load and run up to 9 disk images (DSKs)
      • MultiROMs up to 511 ROMs
    • Recovery mode
      • Install SD kernel directly from the SD card
      • Erase MegaFlashROM SCC+ content
      • Erase SD interface kernel
      • Erase ROM disk
  • Sound
    • Konami SCC and SCC-I emulation
    • Extra PSG emulation (I/O ports: 10h-12h)
      • It is possible to clone the internal PSG sound using the external one.
  • Others
    • Show SD cards information
    • Operates at standard 3.58 MHz as well as at overclocked speeds (tested up to 9.8 MHz)
    • Play EVA video files
    • Allows Konami cartridge combinations
    • Konami sized cartridge
    • Noob friendly

Minimum System Requirements

  • MSX computer with one free slot cartridge (a primary slot)