Industrial Micro Systems - 4 Line Communications Controller
The Industrial Micro Systems Model 480 four line Asynchronous Communication Controller (ACC) interfaced four RS-232C line to the Series 5000 and 8000 IMS Systems.

The 480 unfortunately required 32 I/O address to transfer control and data information between the 480 Controller and CPU.  Control is accomplished by the Western Digital WD8250 Asynchronous Communication Element (ACE).  The Model 480 controller requires one slot in the S-100 bus.  Each serial port is brought to a 3M 26 pin header.  The RS-232-C ports are designed as Data Terminal Equipment (DTE) to connect directly to modems.  To connect to terminals the RS-232 cable wires must be scrambled for Terminal to Terminal connection.

The manual for this board can be obtained here.

Other IMS S-100 Boards
16K RAM   32K RAM    64K DRAM    80186 CPU    FDC 400    FDC 930    HDC    IO Board    Z80 CPU  
8K RAM   4 Line Serial     CPZ 4800   LANS100    CPS-Q6A   Other Boards