In a message dated 3/27/2000 12:35:30 PM Pacific Standard Time, at258(a)osfn.org writes: I believe the 580 is a Z-80 machine, not an intel 8080 processor. Another PN used for the Z-80 is the MK3880P-xx where xx=speed & P=plastic case. The '-10' indicates a 10 Meg HD. They could come with several different brands of drives. CPM or MPM was usually the operating system. there is a separate supervisor terminal port to administer the system. I think there were three user ports and two serial ports, one for a modem and one for a printer. I had about 10 of these at one time. Sold the last during my warehouse sales. I have had several up and running. They are easy. Plug a terminal into console. Wyse 100 or 50 terminal emulation. usually 9600/8/N (Hmm I can't remember the stop bits) Put a current limiter on the power line when you power it up for the first time. Make sure it is warm (room temp) and not cold Paxton