Config Files

Various TerraOnion products support the use of config files to either override or expand the capabilities of these devices on a per game basis. They are simple text documents with instructions that are saved with the file type ".cfg" and dropped along side either cartridge of CD images. This page will document the various options.

MegaSD Config

MegaSD config files are primarily used to change the attributes of cartridge games. To use your cfg file should be the same name as the game image to which you'd like to apply the parameters. (ie: Sonic the Hedgehog.cfg) Here is a list of attributes and values:

MEGAKEY

Megakey allows you to force an alternate region on a rom. Useful for playing "world" roms in alternate languages. (Such as the Bare Knuckle series)

• 0 Off - overrides default in MegaSD settings
• 80 JP
• 81 JP/PAL
• 82 US
• 83 EU

Mapper

Mappers are two digit codes that attempt to load a rom with an instruction set other than the anticipated one. There are dozens of these so we will list only ones that have specific uses.

• 2E Use this mapper if you want to load a Sega CD bios as a rom image

MODE - Saturn Config

Create a text file called mode.cfg and place it in a game folder. Use one of the codes below where "Flags=XX" TerraOnion will hardcode these fixes when possible in new firmware releases so the need for the config file is typically temporary.

• 00 Override all Presets
• 01 No Fastboot
• 02 Bios Fastboot
• 04 Alternate Reset to MODE (not used)
• 08 Boot from CD Screen
• 10 Reset to CD Screen to MODE
• 11 No Fastboot & Reset to CD Screen to MODE
• 12 Bios Fastboot & Bios Reset to CD Screen to MODE
• 18 Boot from CD & Reset to CD Screen to MODE
• 20 Clear wram on boot
• 40 Clear loram on boot
• 60 Clear wram & loram on boot
• 80 ?? Fix for games with crashing video??

MODE - Dreamcast Config

Create a text file called mode.cfg and place it in a game folder. TerraOnion will hardcode these fixes when possible in new firmware releases so the need for the config file is typically temporary.

There are 2 options supported:
BlockDelay=xx
00 for maximum, then milliseconds per 4 sectors block

Flags=xx

• 1 set locked dma transfers
• 2 set locked command transfers
• 4 set locked pio transfers
• 7 set all of the above
• 8 enable seek time

All typical configuration with everything "to the max" would be (this is used for Atomiswave games primarily):

BlockDelay=00
Flags=7