Random access memory with volatile data storage

Claim 1

A random access memory, comprising a plurality of sub-memories, each having an input terminal, an output terminal and a plurality of cells for volatile information storage which are serially connected between said input and output terminals of each sub-memory, rewrite means connected to the output terminal of each sub-memory for recirculating and rewriting each said sub-memory output, output means coupled to each said sub-memory for receiving at least one rewritten information element per sub-memory when it appears on the output terminal of said sub-memery, selection means for producing a signal for selecting a predetermined sub-memory in order to supply an information element, from said sub-memory and through said output means, to an output of the random access memory, input means having an input which is connected to an input of the random access memory and an output which is connected to inputs of the sub-memories for storing modified information therein, clock pulse generator means for shifting the information elements serially and repeatedly through the sub-memory cells under the control of the clock pulses of the clock pulse generator means, a counter coupled to said clock pulse generator means, at least one further cell for volatile information storage coupled to the output of each sub-memory in order to receive rewritten information therefrom under the control of a counter position of the counter, said counter having a number of counting positions which at least equals the number of cells in each sub-memory, the counter passing through its counting positions under the control of the clock pulses in synchronism with the shifting of the information elements in the sub-memories, and said selection means being connectable to outputs of said further cells.