OS X with the Keyspan Twin-Serial USB adapter ... It's supported under OS X. It was really frustrating, because it appeared to just ignore my requests to change the serial connection options, which I'm sure was the problem (wrong speed or something). It sucks especially because I would reboot the Empeg, and I would see the blocks of garbage that were obviously the startup messages, but I wasn't ever able to make it not be gibberish ... And of course, I have no idea if was the serial cable that quite right, or the serial adapter not quite right, or the settings for the adapter........
Mike