1. A digital data storage system comprising: A. a storage register for storing a data word having a predetermined number of data bits along with an error correction code; B. a data input circuit for receiving an input data word having a number of data bits having a selected larger number of data bits than can be stored in said storage register and for generating an error correction code value in response to all of the data bits of said input data word, said data input circuit providing the data word for storage in said storage register comprising the predetermined number of data bits of said input data word along with the error correction code value, the error correction code value being stored in said storage register as an error correction code; and C. a data output circuit for retrieving the data word and the error correction code stored in said storage register and for performing an error correction operation in connection therewith to generate an output data word corresponding to the input data word provided by the data input circuit, said output data word having the number of data bits of the input data word.