| 摘要 |
Data capacity mismatches between a communication node, including end node work stations, and a communication link usually require large buffer storage to prevent the loss of transmitted data frames due to transmission of an incomplete frame. Transmitted data frame continuity is maintained in the present invention by using small FIFO buffers in the node to store small portions of a data frame as data is sent and received. In addition, the data frame is maintained by stretching the transmitted frame on the link when necessary to prevent loss of the frame and compress the stretched frame when it is received from the link. The stretching and compressing is accomplished by inserting and removing non-data symbols, or command code words, in the transmitted and received string of data words. Small FIFO buffers (much less than a data frame in data capacity) operate on the fly to transmit and receive data without requiring contiguous transmission of a complete frame. At the sending node, non-data symbols are inserted in the frame between data words to fill gaps between strings of data bytes. At the receiving node, the non-data symbols are stripped from the received data frame to separate non-data symbols from data bytes. The non-data symbols are encoded command code words used to communicate status between the transmitting node and the receiving node. Transmitted encoded commands convey to a receiving node the status information of the transmitting node. The commands include Ready and Busy to indicate to the node at the opposite end of the link the status of the receive FIFO buffer in the node sending the commands. <IMAGE>
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