Well, its been done in reverse, such as with the Ethernec module, it adds a few mulitplexed lines with some simple TTL's and gives an Atari ST through its cartridge slot an ISA 8bit slot, then you plug an NE2000 compat. ethernet card into it, load up the STing drivers in MINT and you're networking with an ST. I don't know if it honestly would be worth the time to try and build something in reverse so such a narrow purpose. Have you tried to just read the rom's on the cart, then do a copy rom1.bin /b + rom2.bin /b + rom3.bin /b + rom4.bin /bin = stcart.bin /b There aren't many ST carts as it is, so this would probably be the better route to go. It's what we've been doing for years with Atari 2600, 5200, 7800, 800/XL/XE carts.... Curt Ram Meenakshisundaram wrote: -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.362 / Virus Database: 267.12.7/156 - Release Date: 11/2/2005