Protection Against Shift Faults in Disk File Interface
Original Publication Date: 1987-Mar-01
Included in the Prior Art Database: 2005-Feb-01
A disk file interface includes a serializer/deserializer (SERDES). When an input byte is fed to the SERDES, its parity bit is stored. A parity generator operates on the input data, and the parity generated is checked against the stored parity bit. In addition, an echo check comparator detects inequalities between a byte without a parity bit sent to the file and the same byte received from the file. The figure shows a simplified version of a disk file Serial Control Interface. Parallel Serial Control data is transmitted by serializing the contents of an 8-bit register (not shown) which has been previously loaded by a microprocessor. A Parity Bit is not transmitted to the disk file in order to reduce transmission time.