Important: Both frontends discussed in this article have been discontinued for some time, and neither will function with the most current versions of O2EM. Today, the frontend of choice is O2EM Launcher, which is not discussed in this article. The article has been left as-is for reference purposes.
A long time ago, Erik Winblad e-mailed me about his O2EM "frontend," a Windows-based program that allows point-and-click selection of the games for the Odyssey² emulator. I was excited, but I couldn't check it out because my old computer system was too primitive to run it (my system was way out of date). Then, somewhat later, I received another e-mail from Frank Chiappetta, about a new O2EM frontend that he'd designed. Again I faced the same problem and both programs have been sitting on my hard drive, untouched. But now I have a new job and finally purchased a new computer, so of course one of the first things I did with it was check out these two authors' work. And I must say, I wish I'd had this computer before, because I was missing out!
Originally I was going to write a review of each frontend, but as you can tell from the screenshots, they contain much the same features, so I'll just describe them. Essentially what you get is a scrollable list of the .BIN game files that occupy the same directory on your hard drive as the frontend program. Simply pick the one you want, double-click it or hit the "Run Game" button, and start playing! Both frontends allow you to configure Controller 1 and 2 to use the left or right keyboard or a joystick. Both also allow you run O2EM in Debug Mode, or to turn sound effects off. O2EMUGUI has an additional option that lets you turn Voice emulation off, but selecting "No Sound" on Oxygen will mute Voice as well. Also, both frontends have an option to limit the emulation speed.
There really is very little to set the two frontends apart. Both of them ran my games with no trouble. About the only complaint I have is that Oxygen seems to employ a less intuitive keyboard control layout. Oxygen is noticeably smaller, in terms of file space, than O2EMUGUI, but with today's hard drives that shouldn't make much difference. O2EMUGUI comes with its own installation utility that automatically creates a shortcut on your Windows taskbar. With Oxygen, you just unzip its two files into the directory containing O2EM.
Other than this, there's really very little difference other than appearance. O2EMUGUI is prettier than Oxygen, containing scans of Odyssey² catalogs in its active window. Still, I'd recommend downloading both and deciding for yourself which one you like. (You can download each one at the bottom of this page.)
I'd like to congratulate both authors on their work and apologize once again for taking so long to get this page up. Hopefully they'll continue to support these frontends in the future. It might be nice to include support for screenshots, and maybe even provide on-line instruction manuals. We can only hope!