| 摘要 |
PURPOSE: A host digital terminal in a demand-concentrated optical subscriber transmission system is provided so that an ATM cell bus can be divided into upward and downward buses, and each functional unit can perform a cell bus connecting operation without using a commercial chip. CONSTITUTION: A host digital terminal(210) includes an ATM cell bus(213) consisting of a predetermined number of upward ATM cell buses and downward ATM cell buses. When transmitting an ATM cell via the ATM cell bus(213), each functional unit of the host digital terminal(210) converts a virtual path identifier(VPI) value of the ATM cell into a corresponding value, and transmits the ATM cell with an address and a port number of the functional unit receiving the ATM cell. When receiving the ATM cell via the ATM cell bus(213), each functional unit compares the address transmitted with the ATM cell with its own address, receives the corresponding ATM cell, and outputs the ATM cell to a port corresponding to the port number. |
