| 摘要 |
<p>A multi-media network bus (MMN-Bus) and Controller (MMNC) serve as a distribution medium between a single high-speed network and multiple user network interfaces (UNIs). The MMNC allocates multiple isochronous channels and packet channels for distribution to the users over the MMN-Bus. The MMNC sends information in standard time segments or master cycles. Following transmission of a start signal, a series of control blocks is sent. The first type of control block is used for communication from the MMNC to each UNI. The second type of control block is used for transmissions from each UNI to the MMNC. Both types of control blocks are used for call setup, call acknowledgement, channel allocation, call end and packet data request. Following transmission of both sets of control blocks, a signal is sent to indicate the beginning of a sequence of isochronous transfers. Each UNI tracks the number of signals, identifying those signals which it should either receive or transmit. Following the end of the isochronous channel transmissions, two things occur. First, the MMNC sends the address either of itself or the address of a UNI. (This address is sent continuously until the end of the transmission of the related packet.) Subsequently, a start packet signal is sent which indicates the beginning of the packet transmission by the unit whose address was sent. Each packet contains a destination address. Each UNI and the MMNC check the destination address against their own address: if it matches, the device receives the packet. An end packet signal indicates the end of the transmission of the first packet. <IMAGE></p> |
