Sega wanted PlayStation games running on Dreamcast more than it could publicly admit, according to Bleem programmer Randy Linden.
Bleem began as a commercial PlayStation emulator for Windows PCs, then moved onto Sega's final console as Bleemcast. In a career interview with Zophar, Linden said Sega was excited by the idea and supplied the team with Dreamcast documentation and development hardware, even as the company stopped short of officially licensing the emulator.
"I took a look at the specs for the Dreamcast and thought, 'Yeah, it could be done. Absolutely. Let's get in contact with Sega.' So, we got in contact with Sega, and Sega was thrilled at the idea, and they sent us all the technical specs for the Dreamcast. They loaned us a Dreamcast hardware development system, including a GD-ROM writer and all the necessary software to do the development."
That quiet support came with a hard boundary. Linden said Sega would not license the GD-ROM format or allow Bleemcast to ship as an official Sega product unless Sony gave permission, which was not a realistic outcome for a PlayStation emulator.
"They did not want the title to be licensed officially by Sega. Because they didn't want to get into a big legal battle with Sony. They would happily license the GD-ROM format and allow us to use their libraries, their code, their whatever, if we got permission from Sony, right? Which was not going to happen. So that meant that everything written for Bleemcast was written from the ground up."
Linden added that Bleemcast used no Sega libraries, no Sega code and no Sony code. Instead, the team relied on low-level Dreamcast hardware documentation and built its own path around the console.
Bleemcast found its route through Mil-CD
The workaround came from the Dreamcast's Mil-CD support. Linden said he reverse engineered the Sega BIOS and was nudged toward buying Heartbreak Diaries, a Japan-only Mil-CD release that contained Dreamcast boot code.
Mil-CD was designed to let standard CDs include multimedia features such as menus, internet options and small programs. According to Linden, Sega saw it as another revenue stream, but did not want the format widely known.
That opening let Bleemcast run from a standard CD instead of Sega's GD-ROM format. It also helped create a broader Dreamcast homebrew and piracy scene, including the Utopia boot disk and self-booting CD-R copies of Dreamcast games.
The story is a sharp reminder of how strange the Dreamcast era became near the end of Sega's console business. Bleemcast was not just a fan experiment. It was a commercial emulator that put selected PlayStation games on a rival console, with Sega apparently helping from the shadows while trying not to invite a direct legal fight with Sony.