SEMICONDUCTOR MEMORY

PURPOSE:To obtain a memory for variable data capable of improving the throughout of a system by providing the memory with a counter to count the continuous number of data and a memory part to store a data number to execute the reading of the data from a memory part for storing data based on the data number stored in the memory part. CONSTITUTION:The memory is constituted of three memory mats MM1-MM3, three updown counters UDC1-UDC3, a control circuit CNT. At the time of back-track processing, the change of an epoch is executed when a variable data number is inverse-operated to comes to zero, and an address within the memory mat for address conversion MM1 is rewritten with the change of the epoch. By a means, since the back track processing is executed not with software but with hardware, the burden of a microprocessor is reduced and the throughout of a system can be improved. Thus, a memory for variable data which can improve the throughput of the system can be obtained.