Voice Data State; Voice Data Transmission State; Voice Data Receival State - ZyXEL Communications 2864 Series User Manual

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 trans-
mission to the remote station, and the DCE transfers data to the DTE after recep-
tion 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 con-
necting 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 con-
nects 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 <DLE><ETX> 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.
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