RT-11 came on the hard drives when I got the 11/23's. I have both v5.1 and v5.3. I mainly use RT-11 to check out systems as they are being assembled, and to run disk utilities. Although you can download RT-11 from the web, the license restricts its use to running under simh. Mentec owns and maintains RT-11. If you want to buy a legal copy from them, it costs something like $1500. At present, there is no hobbyist version.

Wikipedia article for RT-11 here.

Last modified: December 31, 2009