RANDOM ACCESS MEMORY

摘要

A semiconductor random access memory is provided having a second asynchronous input/output port. Block transfers of data can be effected to and from the memory using the second input/output port. Memory throughput efficiency is improved permitting functions such as display refresh in a mapped memory display to be accomplished through the second input/output port. Memory bus contention on the primary port is also relieved. The main input/output port is thereby free to receive new data for a higher percentage of available transfer time since refresh data is available at the second input/output port.