AT&T 3B2/300 Technical Reference Manual page 436

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CM195AC/CM195AD "DATAKIT" VCS INTERFACE CARD
General
The Datakit Virtual Circuit Switch (VCS) Interface card provides a high speed fiber optic connection
from a 382 host computer to a Datakit VCS. The connection is made through a combination of the
CMl 95AD Fiber Interface Board (FIB) and the CMl 95AC Datakit VCS Processing Unit Card. Both
cards are standard 382 computer feature cards interconnected by two 40-conductor ribbon cable.
The CMl 95AC Card provides the interface to the 382 computer I/0 bus and implements the Level
C functions associated with Universal Fiber Trunk Interface (UFTI) protocol. The CM195AD Card
implements the point-to-point link functions over the optical fiber. A block diagram of the add-on is
shown in Figure 3-57.
The CMl 95AC Datakit VCS Processing Unit Card hardware consists of five distinct pieces:
• INTEL 80186 Microprocessor
• Input/Output (I/0) Bus Control
• Nonvolatile Memory
• Volatile Memory
• External Interface.
These components are under the control of the INTEL 80186 Microprocessor, unless another
intelligent source wishes to make use of the processing unit memory by asserting a "hold" request.
FUNCTIONAL DESCRIPTION 3-183