3Com TMX 10031161 - Manual (Page 29)

Configuring Non-3Com U.S. Robotics Modems for Use with the TMX 23
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Modem must have an RS-232 standard interface
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Modem’s serial port rate must support 115.2 Kbps
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Modem’s serial port must be configurable to support
hardware flow control
If your modem meets these minimum requirements, it may
be used with the TMX cable modem, but please remember
that the quality of your external analog modem directly
effects the performance of your cable connection.
In addition to meeting the basic requirements, your analog
modem may need to be configured to work properly with
the TMX cable modem. The included configuration
software provides a "Cable Modem Configuration" screen
which can be used to pass additional parameters to your
analog modem. These parameters are AT command strings
used during initialization. Since the parameters are often
manufacturer specific, list below is the optimal
configuration. The characters in brackets are the equivalent
3Com U.S. Robotics modem commands. Please refer to
your analog modem's user manual for the exact AT
commands. It is not necessary to enter AT into the
parameter field, only the command parameter.
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Return result codes in words [V]
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Serial port rate higher than connect rate [&B1]
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Transmit data Hardware flow control [&H1]
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Receive data Hardware flow control [&R2]
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Auto enable V.42 Error correction [&M4]
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Auto enable V.42bis data compression [&K1]
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ITU-T (formerly CCITT) answer sequence [B0]
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Carrier Detect follows connection (&C1)
For example, in order to program your analog modem as
described by these commands, you would enter the
following string into the "Use User Initial" field on the
"Cable Modem Configuration" screen:
V&B1&H1&R2&M4&K1B0&C1
Since the quality of analog modems and telephone lines
varies greatly, in most cases V.42 error correction and
V.42bis data compression should be used. In other