5634BIF User’s Manual
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4.4 Configuring for reliable operation
To communicate with remote MNP modems only :
1. Type
AT\N5
2. Press the Enter key. Your modem responds with OK. When your modem originates or
answers calls, it will try to make an MNP connection. If that fails, your modem will
hang up and return to command mode.
To communicate with remote V.42 modems only :
1. Type
AT\N4
2. Press the Enter key. Your modem responds with OK. When your modem originates or
answers calls, it will try to make a V.42/V.42bis connection. If that fails, your modem
will hang up and return to command mode.
4.5 Turning off error-correction
To turn off the MNP/V.42 error correction and communicate with non-
MNP/V.42 modems:
1. Type
AT\N0
and press the Enter key to return to standard operation with buffering. or
AT\N1
and press the Enter key to return to standard operation without buffering
2. Your modem responds with
OK
.
4.6 MNP5 and V.42bis data-compression
There are two major data-compression protocols used in data communications, MNP5 and
V.42bis. MNP5 was the first data-compression protocol to be developed and provides a
data-compression ratio of 2:1.
In January 1990, ITU-T ratified the V.42bis data-compression protocol as the international
standard. V.42bis performs significantly better than MNP5, providing a data-compression
ratio of approximately 3:1
−
and in some case, up to 4:1.
By supporting both types of data-compression protocols, your modem can communicate
with the installed base of MNP5 and V.42bis modems and modems.
To communicate with remote MNP5 modems
only
1.
Type
AT%C1
2.
Press the Enter key. Your modem responds with OK. When your modem originates or
answers calls, it will try to make an MNP5 connection. If that falls, your modem will
hang up and return to command mode.
To turn off V.42bis and MNP5 data compression:
1. Type
AT%C0 ;
Press the Enter key. Your modem responds with
OK
.
Summary of Contents for 5634BIF
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