Voice Data States - ZyXEL Communications Omni 288S User Manual

The Voice Command State provides several DTE options. The modem may wait
for an unspecified time after playing a welcome message, or switch to other
modes as part of a DTE call discrimination algorithm.

Voice Data States

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 voice to analog
(e.g., microphone). The DTE transfers data to the DCE for transmission to the
remote station. 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
to the remote station, and pertaining to requests from the DTE.
Voice Data State has two sub-states. These are Voice Transmission State and
Voice Reception 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 busy.
The Voice Data Transmission State is terminated by either of the following two
methods:
1. The DCE receives a <DLE><ETX> shielded code from the DTE.
2. When a DTE/DCE inactivity time-out occurs.
After termination of the Voice Data Transmission State, the DCE will enter the
Voice Command State.
Voice Data Reception State
The DCE is in the Voice Reception 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:
Chapter 10 - Voice Mode Operation
10-7