| 摘要 |
<p>A hub featuring several ports for attachment of stations to a LAN comprises concentration logic (14) for the handling of multiplexed incoming and outgoing Token-Ring and isochronous flows from and to the stations. The concentration logic comprises a clock recovery logic (42) from incoming Token-Ring packet data stream (40), for regeneration of Differential Manchester encoded data on output (400), and recovering of Token-Ring clock (401). A cycle framing generator (43) receives a 125 us synchronization clock (local or remote) from the hub backplane (402), and the Token-Ring clock (401), and generates control signals (403) to each of the 10 ports. Each port is made up of a port transmit interface (44), and a port receive interface (45). Data from a station hooked to the hub is input (404) to port receive interface (45). Token-Ring packet Differential Manchester encoded data are output (406) on to the next active port, and specifically to its port transmit interface, along with a recovered strobe clock (405), while ISO data are output (407) to a switch (46). The switch receives a hub local clock (412), which otherwise distributes on the whole concentration logic. isochronous traffic interchange with the hub backplane is ensured thru leads 410 and 411; inbetween ports or between ports and the hub is ensured thru leads 407 and 409 replicated for each port. Data to the station hooked to the hub is output (408) from port transmit interface (44). Differential Manchester encoded data are received (400) along with Token-Ring clock (401). Control signals are input (403). Isochronous data are received (409). Token-Ring packet Differential Manchester encoded data are finally output from the concentration logic (41). <IMAGE></p> |
