Bus Separator Module - RCA COSMAC Operator's Manual

BUS SEPARATOR MODULE
This module is used to interface two unidirectional
data bussesJ(one IN, one OUT) with the COSMAC bidirect-
ional data bus. Data going into the bidirectional bus
is gated via a bank of transmission gates enabled by an
appropriate logic condition. (In the Microkit, two such
modules are used -- one to interface to the memory system,
the other to interface to the I/O system. Wiring of the
two connector pins carrying the function select signals
distinguishes the memory bus separator from the I/O bus
separator.)
FUNCTION
SELECT (2)
MEMORY
CONTROL
(2)
ENABLE
TRANS-
MISSION
CAIE(8)
DATA OUT
(8)
DATA BUS (8)
DATA IN
(8)
Fig.12: Block Diagram - Bus Separator Module
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