CRC-Betriebsverfahren und HEC(Kopf-Fehlerprüfung)-Synchronisierungseinheit für ein ATM-Vermittlungsverfahren

摘要

A CRC operating unit (602) performs a CRC operation on received data using as an initial value a CRC operation result actual value obtained in the previous operation, and outputs a CRC operation result actual value. A delay unit (604) delays the CRC operation result actual value by the time taken for a header part to be entered. The CRC operation result derivation unit (605) outputs as a CRC operation result derivation value an operation result obtained by a CRC operation performed for all the receiving data of a header part provided with the above described CRC code using the CRC operation result actual value as an initial value. The coincidence detecting unit (607) compares the CRC operation result actual value with the CRC operation result derivation value to detect the input timing of a header part as coincident timing for both values.