Huawei V200R001 - Manual (Page 12)

User Manual - Configuration Guide (Volume 3)
Versatile Routing Platform
Chapter 2
Configuration of Modem Management
2-6
Example 3: Configure modem initialization parameter
Correctly initialize modem configuration is an important step to connect modem
correctly. The following is a brief introduction to the common AT initialization commands
and work to do for initialization.
z During consulting between modems, modem rates must remain unchanged,
otherwise new rate matching should be performed with AT command.
z Modem locks EIA/TIA-232 serial port rate in different ways. The modem manual
may be consulted to learn how modem locks rate (optional items include &b, \j, &q,
\n or using s register).
z Modem must use data carrier detection (DCD) to indicate the establishment of its
remote connection, such configuration of most modems is performed with &c1
command. Refer to modem manuals for details.
z Modem must allow to hook on its active connection through Data Terminal Ready
(DTR) signal, such configuration for most modems is performed with &d2 or &d3.
Refer to modem manuals for details.
z If the modem is required of call-in function, it must be configured with incoming call
off-hook ringing number, our requirement is not to adopt the automatic answer ring
mode, most modems are configured as S0=0. Refer to modem manuals for
details.
In consideration of the above conditions, our typical initialization string is as follows:
AT&b1&c1&d2&s0=0
Explanation for functionality of the initialization string:
z Lock serial port rate
z Enable
DCD detection
z Enable DTR hook-on function
z Configure as non-automatic answer
The procedure to configure is as follows:
Quidway(config)# chat-script init "" AT&b1&c1&d2&s0=0 OK
Quidway(config)# interface serial 0
Quidway(config-if-Serial0)# start-chat init
2.4.2 Remote Configuration Using Modem and Through Asynchronous
Interface
I. Networking requirements
AS introduced above, modem can be used for remote configuration through Console
interface, Quidway router series also support the remote configuration using modem
through asynchronous interface.