Case Communications syncro 1496, Справочное руководство

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These may be user-modified, but can be recalled to the default
configurations by resetting the modem.
Factory configurations 4, 5, 9 and 10 are suitable for PSTN operation. The
remainder are suitable for leased line (private wire) operation.
Configurations 4 and 5 are suitable for DTEs which issue V.25bis dialling
commands.
The default user configurations are suitable for dial backup operation.
In the following explanations, the full specification of each configuration is
shown as it would be presented on the DTE screen by use of the
*C
command (see Chapter 8). For each parameter it shows the AT command
code, the command name, and the selected option.
Control Signals
The connection between the modem and the DTE includes a number of
control signals, which are monitored by the front panel indicators (see
Section 1.2.1).
The way these signals are used is controlled by the configuration in use. In
the following descriptions of the configurations, each control signal is
described as being in one of three modes. These are:
Normal The signal is sent in the normal manner. In this mode,
DTE signals must be controlled properly by the
originating DTE.
Forced On This can apply to control signals originated by the
modem. The modem sets the signal to the ON state at
all times. It therefore has no meaning as a control
signal, but is used to make the DTE function correctly.
Ignored This can apply to control signals originated by the
DTE. The modem ignores any changes in the signal
state and behaves as if the signal were permanently
ON. It is not necessary to have a connection to the
signal's pin on the DTE port connector.
Note that these modes can be changed by AT commands (described in
subsequent chapters).
For details of the significance of the control signals, refer to ITU-T
Recommendation V.24.
X450-310851 Issue 2 4-5 Rev.1