Automatic Correction of Multiple Errors Originating in a Computer Memory

An error correction unit has been installed in an IBM RAMAC® 305 to demonstrate automatic correction of burst errors originating in a computer memory. Employing a cyclic code requiring two percent redundancy, the unit has successfully corrected all four-bit and most five-bit error bursts in a 100-character record stored on a defective disk. Details of the error correction unit and test results are presented; two special cases involving block length are also discussed.