Method to Reduce Soft Errors in Control Stores by Use of Self Checking
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-02
To provide error detection and correction, control stores are divided into two halves, each with its own error correcting code (ECC) hardware address counter and controls. Control programs are written such that each half of the control store is used by the system every other cycle. During the off cycle in each half, a separate address counter checks each address (one per off-cycle) to detect and correct an error using ECC. Thus, soft errors are nearly completely eliminated and hard errors are detected by a recheck and further use of a bad address may be avoided.