Rany Battikh

Mega SD Firmware update (December 2019)

Terraonion just released firmware 1.04 R07 for their Genesis/Sega CD/Master System rom-cart, the Mega-SD:  https://bit.ly/terraonionmegasd

So many new impressive options have been added this time around, like the directory cache feature, save ram backups, doubling the size of the CD RAM cartridge and the much requested MD+ audio fade command among a whole slew of bug fixes and menu improvements.

Here’s a detailed list of what to expect when updating the Mega-SD to the latest firmware:

  • Directory cache. The first time you enter a folder, MegaSD will build a cache of files, directories and types, so the next accesses to that folder are instant load. The folder contents will be rescanned when a new file or directory is added. To force a rescan, enter the folder by pressing START instead of A.
  • Create save ram backups, so if a write fails or the data is corrupted, the backup will be loaded next boot.
  • Add Wondermega/X’Eye audio effects (Left only, Right only, Voice cancel). Only available when using the wondermega/x’eye bios cd player.
  •  Add a mapper to support Game no kandume.
  •  Support 4MB SMS Roms.
  •  Double the size of available space for the CD RAM Cartridge. Note that if you already have files stored in your CD RAM, the space won’t be increased. You must either delete your SRM file entirely from the BUP folder, or just delete all files from your CD RAM Cart in the bios memory manager. When there are no files, the space will be automatically doubled.
  •  Wraparound in the game list. Only wraps if buttons are released and pressed again when reaching the first or last page. It won’t wrap if reaching the pages by holding a button.
  •  Add an option to remember the last selected game and directory when returning to game list.
  •  Add a MD+ command to support arbitrary specificacion of sector start, end and loop points to play CD Audio, instead of specifying a track.
  •  Add MD+ CD audio fade commands.
  •  Add MD+ command to play .WAV files.
  •  Add MD+ command to load files from the SD card directly to ROM area.
  •  Add MD+ command to read SD card directories.
  •  Allow specification of MD+ loop points in cue files. They override the loop data specified in commands.
  •  Improve SMS FM to fix sound problems in Phantasy Star
  •  Fix Megarace CD game missing sounds.
  •  Fix Megaman (US) showing in-game menu after sega logo.
  •  Fix Sonic & Knuckles (without locked on cart) booting to the “No Way” screen.
  •  Fix NHL98 and other EA ’98 megadrive games SRAM not working due to missing backup RAM header.
  •  Fix Compton’s encyclopedia hanging at the end of some videos.
  •  Fix Kriss Kross (US) audio stuttering.
  •  Fix some japanese Wolfteam games that didn’t boot with graphics speedup off.
  •  Fix Snatcher incorrect graphics showing in a specific scene due to the reported CD read position being off by 1 sector.

Terraonion even added support for the Sega Mega Drive Mini Japanese (and previously Sega Channel) exclusive compilation Game no Kanzume Otokuyou’s mapper. Also, the addition of the new MD+ commands makes creating and accessing MD+ patches a much simpler process.

Mega-SD owners should definitely update their carts and benefit from all the new offerings that the new firmware is providing them with.

Just login, download the latest firmware, place the .upd file at the root of the SD-card and let the cart auto-update: https://downloads.terraonion.com/login