I have two Harris 500 control panels. The Harris H-Series was a series of 24-bit machines they called super mini-computers in the late 70's and early 80's. I think it would be fun to add this architecture to SimH and using blinkenbone to make one of the panels work. But, I can't seem to find any software for this system. The company is long gone, so I would hope someone would put something onto bitsavers if they had it sitting around somewhere. Let me know if you have something sitting around. I would love to learn more about this more obscure system.