Serially operating data protection system - has bistable flip=flop changing state with first information bit in specified way in presence of parity bit

摘要

The data protection system uses parity bits to check correctness of data. The first bit in the data word sets a bistable flip flop at the transmitter into the same or opposite state as the bit depending on whether the word has to be made up to an even or odd number of bits. At the receiver the bistable flip flop changes to the 'word correct' state if the first bit is 0 and a parity bit is present and into the 'word wrong' state if the first bit is 1 and a parity bit is present.