| 摘要 |
Apparatus and method for providing communication between two computers over a communications network and for detecting a command word received form the network for interrupting normal communication. In one embodiment, the apparatus includes a first part for organizing data transmitted onto the network in asynchronous format such that the data is arranged in frames with a flag designating the start of each frame and having an interframe period between each frame during which data is not transmitted. Each frame has a time period less than the predetermined time of transmission of the command word. The apparatus includes a second part responsive to the command word for interrupting normal communication, and a third part responsive to the flag for placing the second part in a disabled state for the time period of each frame, and when the frame time period is complete, for enabling the second part to respond to the command word during the interframe period. In another embodiment, a defined number of contiguous data bytes are counted after receipt of the first command code. If a prescribed number of command codes are received during the defined count of contiguous bytes, communication is interrupted. The apparatus also provides for digital detection of a digital dial state indication signal sent by the network and for dialing on the network in response to the digital dial state indication signal. Furthermore, data is transmitted to and from the network in asynchronous format synchronized to the line frequency of the network.
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