摘要 |
In a stored program controlled electronic telephone switching system transmission links are provided from a host office, provided with a central processor, to one or more remote offices, each provided with a remote processor. Data and control information are continually passed between the host office and each remote office in a digital time-division format. Data integrity is monitored through a cyclic odd and even patterned parity scheme which predetermines the parity of sequential time slots in one direction of transmission and reflects that parity pattern in the return direction of transmission between host office and remote offices. The patterned parity scheme detects hardware faults in the interface for the transmission links between host and remote offices on a continuous basis. |