| 摘要 |
A polled digital multiport, multidrop system is described. The inbound frame for sending information from remote terminals (42) to the host terminals (12) is arranged such that a plurality of bytes are provided by a first terminal, followed by a guard band, followed by a plurality of bytes provided by a second terminal, followed by another guard band, etc. The guard band permits signalling between the DSU (16, 36, 116) and the OCU (24), which in turn permits the OCU (24) to signal the MJU (28) that no data will be coming from the OCU (24). In this manner, control mode idle is accomplished and data mode idle is avoided. In addition, because of the guard band, if the delay from a remote site changes, no data will be lost. Means for monitoring the system (154) to follow changes in delay are also provided, and the system can cause a remote location to accommodate a change in delay. |
