The ACS-586 was a multipost system which could handle 5 users or more (8) with optional cards. To connect the terminals, there were several RS232 ports at the back of the system, labeled JA, JB, JC, JD, JE, etc... The ports not used by the terminals could be used to connect any serial peripheral, i.e. modem or printer.
The 186 was the first computer from a big company to use Xenix as its native operating system. Xenix was the Microsoft "adaptation" of Unix.
This system was quite well designed with its squashed hexagon shaped box and its thin monitor. These were medium-sized desktop cases, usually beige but often came in custom colors.
A fully-loaded 586 contained four printed-circuit boards.
The main board held the 80186 and 512 KB of RAM; a Z80 I/O processor supporting six serial I/O ports, floppy disc access, and an RN422 LAN; and sundry memory management components allowing the 586 to support Xenix.
A second board held a hard disk and tape controller with an Intel 8089 I/O processor
An optional communication board provided an Ethernet chipset and processors supporting either the X25 or SNA protocols, or four additional serial I/O ports.
The fourth board was an optional memory expansion board providing an additional 512 KB of RAM.
It had a 5''1/4 disk-drive built-in on the right part of the front panel, and a hard-disk on the left part.
A real-time clock was included with the system. There were 128 semi-graphic symbols available.
The Altos 686 appears to be the same machine as the 586, but with an 80286 processor.
Altos also produced an 8-bit version of this system, called the ACS-580.