| 摘要 |
PURPOSE: The system for switching packet messages in an exchange is provided to switch packet messages having variable input/output speed when the speed of an input message link and an output message link is variable. Accordingly, a line board can transmit the packet messages right after ending data protocol processing, so that a message delay can be prevented and the line board, and a high capacity message switch can be variously connected according to system specs. CONSTITUTION: An effective message detector(61) receives a clock and data from a high capacity message switch or a line board, to checks a flag of an HDLC(High-level Data Link Control) frame and a CRC(Cyclic Redundancy Check). An address checking unit(62) decodes an address of data passing the effective message detector(61), to supply an enable. A multiplexer(63) multiplexes the data passing the address checking unit(62), according to the enable supplied from the address checking unit(62). A serial queue controller(64) converts data multiplexed in the multiplexer(63) into parallel data, for storing. Serial queues(65-1/65-N+M) store the parallel data as packet messages, according to a control signal of the serial queue controller(64). A data checking unit(66) periodically checks the existence of effective data in the serial queues(65-1/65-N+M), to read effective data from the serial queues(65-1/65-N+M). An output driver(67) delivers a clock according to a data ratio of an output port, and transmits effective data to a corresponding output port through the data checking unit(66). |
