Communication system which in a first mode supports concurrent memory acceses of a partitioned memory array and in a second mode supports non- concurrent memory accesses to the entire memory array

摘要

A communication system is provided that includes a mechanism for selectively addressing memory banks depending upon the configuration of that system. The communication system can therefore operate in accordance with two possible modes of operation. According to a first mode, the local CPU can access one set of memory banks concurrent with an external device accessing the other set of memory banks. According to a second mode of operation, either the local CPU can access the memory banks or an external device can access the memory banks, one exclusive of the other. In one version of the second mode of operation, address signals to the memory banks can be physically connected leaving signals free to be used as general purpose input/output signals. The mechanism by which memory banks can be addressed and data transferred to and from those banks readily lends itself to communication applications to which the present system may be attributed.