Case Communications syncro 1496, Справочное руководство

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2.2 Equipment Requirements
2.2.1 Data DTE
Your data DTE must operate synchronously. Note the following points:
• If you are using a PC, the standard serial port provided in most models
operates asynchronously; to use a PC for synchronous data, you need a
Synchronous Communications Adapter (consult your PC supplier).
• Simple terminals (VDUs) are usually asynchronous, although special
models designed to work synchronously are available.
• Most wide area and local area networking equipment will operate
synchronously.
2.2.2 Controlling the Modem
To control your modem, you will need to send AT commands to it. (V.25bis
commands are a special case, discussed in Chapter 10.)
For sending AT commands, you require a separate asynchronous
command terminal with the following character format:
1 start bit, 7 data bits, even parity, 1 stop bit.
The data rate must be 9600 bps for a standalone modem or rackmount
controller card, or 1200 bps for a rackmount modem via a Y cable.
This terminal will be connected to the standalone modem's command port.
The command port for the rackmount modem is normally routed to the
rack Controller Card. Appendix B contains details of how to route the
command port via the DTE connector.
X450-310851 Issue 2 2-2 Rev.0