Install and Connect Modems
Task List: Install and Connect Modems
704
SI Installation and Upgrades
June 2004
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Add U.S. Robotics Model USR 33.6 EXT
External Modem to EPN
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1
Connect an RS-232 cable to the modem. See
Figure 285, Connect External Modem to EPN,
on
page 705.
NOTE:
In the following steps, a PC with Windows 95 or Windows NT 4.0 may be substituted for
the dumb terminal. Use the Hyperterminal (terminal emulation) application.
Disable Data
Compression
Turns off the default data compression algorithms used by most modems. The
field has a blank field of 6 characters as default. The AT commands that control
this are supported by similar commands; however, these commands do not
operate in the same manner. The Intel modems require H0%C0 to disable
V.42bis & MNP Class 5 data compression algorithms. The Paradyne products
only use%C0 to disable both algorithms. This field is not case-sensitive.
Enable Error
Control
Turns on the V.42 LAPM and MNP error control protocols. The field has a blank
default of 6 characters. The Paradyne products use the command \N5 to enable
V.42/MNP/Buffer error control while the Intel product uses \N3 to provide
similar functionality.
Misc. Init.
Param
This field has a 20-character blank default and supports any initialization
parameters not already specified. The AT commands specified in this field are
always the last initialization parameters to be sent to the external modem. This
field is not case-sensitive.
Auto-Answer
Ring Number
This field controls the number of rings required before the modem answers an
incoming call. This field should be set to S0=10.
Dial Type
This field controls the type of interregister signaling used between the modem
and the CO. This 3-character field is denoted by “T” for tone dialing (default)
and “P” for pulse dialing. This setting depends on type of line (tone or pulse) to
the modem.
Adjustable
Make/Break
Ratio
This field controls the make/break ratios of pulses and DTMF dialing. Most
modems have support for different make/ break options for pulse dialing only.
Paradyne, Intel, and U.S. Robotics use the default &P0 to select a ratio of 39%
make and 61% break for communication for the United States and Canada. The
option &P1 sets a ratio of 33% make and 67% break for the United Kingdom and
Hong Kong. This is a 5-character blank field (default) and is not case-sensitive.
Dial Command
This field has a default of “D” in a 3-character field. This field denotes the
standard dialing command of the modem and is not case-sensitive.
No Answer
Time-Out
Most modems provide a timer that abandons any outbound data call after a
predetermined interval. This is a non-administrable parameter.
SCC1 Modem Fields
Field
Description
