ZyXEL Elite 2864 User Guide - Page 180

Voice Data State The DCE is in Voice Data State when the DCE is operating in voice mode and is communicating with a remote station or with one or more local devices which are capable of translating analog signals to voice (e.g., speaker) or translating voice to analog signals (e.g., microphone). The DTE transfers data to the DCE for transmission to the remote station, and the DCE transfers data to the DTE after reception from the remote station. The DCE monitors data and the control signals to detect events which the DCE later reports to the DTE pertaining to the line connecting the DCE and the remote station, and pertaining to requests from the DTE. Voice Data State has two sub-states: Voice Transmission State and Voice Receival State. Voice Data Transmission State The DCE is in Voice Transmission State when the DCE receives digitized data from the DTE, converts the binary data into an analog signal, and transmits the analog signal to the remote station or to one or more local device destinations such as a speaker. While transmitting the data, the DCE - (1) - monitors the line which connects the DCE to the remote station or to one or more local devices to detect events which the DCE reports to the DTE and - (2) - does not expect to receive, digitize, or process any incoming analog signals for transfer to the DTE. Events detected when monitoring are notification signals such as ringing. To leave the Voice Transmission State you may use either of the following two methods: (1) A shielded code is received from the DTE. (2) A DTE/DCE inactivity timer time-out occurs. Item (1) is the DTE-initiated method to terminate the Voice Transmission State, and item (2) is a DCE-initiated means of terminating the Voice Transmission State. Upon termination of the Voice Data State, the DCE will enter the Voice Command State. Voice Data Receival State The DCE is in the Voice Receival State when the DCE digitizes the analog signal from the remote station or from local device sources such as a microphone. The analog signal is converted into binary data, which is compressed or otherwise processed. The resulting data is transferred to the DTE. While receiving the data, the DCE (1) monitors the line which connects the DCE to the remote station or to one or more local devices to detect events which the DCE reports to the DTE. These events pertain to signals carried over the line such as tones, and to PSTN-generated control and notification signals such as ringing. 16-4