Abstract: Memory system having contiguous storage locations with sequential addresses is partitioned into units to permit separate unit write-in and parallel unit read-out, operations. Each unit is responsive to common word address signals and unique combinations of block address signals. In response to a control signal in a first of two possible states, the memory system operates in a conventional manner, i.e., data is read from or written to a particular location in the memory to or from a data bus, the address of the particular location being supplied over an address bus and having a block select portion and a word select portion. When the control signal is in its second state, each unit is responsive only to the word address signals to read data from or write data to common word locations in each unit simultaneously.