Black Box 32144, Руководство пользователя

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29
CHAPTER 2: Quick Start
Terminating a Data Call
Normal termination of a data call is
processed through communication
software. An alternate method is to
switch to the HANGUP option on
the AUTO-DIAL screen. Another
method is to drop the DTR signal
from the DTE (by software control
or by turning the DTE off).
For manual originate/answer
operation, see Chapter 4 .
2.5 Leased Line (2- or 4-Wire) Mode
(Quick Setup 6–9)
This section does not apply to V.33
leased-line operation. For V.33
leased-line operation, see the next
section.
The following information
applies to both 2-wire and 4-wire
leased line operation:
• The modem must be
configured for the correct line
type—2-wire or 4-wire. If you
have selected the correct
Leased Line Quick Setup,
the line type will be set
automatically to the
correct setting.
• One modem must be set to
originate mode and the other
to answer mode. If you have
selected the correct Leased
Line Quick Setup, the
answer/originate status will be
set automatically to the correct
setting.
• Leased line operation is
restricted to data rates of
4800 bps or higher.
• Lines can be conditioned
or unconditioned.
Four different leased-line Quick
Setups are available (not counting
V.33 leased line operation), as
shown in
Table 2-1 . After you select
the appropriate leased-line Quick
Setup, the answer unit immediately
generates an answer tone that
signals the originate modem to
begin the training sequence,
meaning it is ready to “handshake”
with the originate modem.
When the local modem has
established a connection with the
remote unit, the EIA status screen
should be present. Typically this
screen will look like this:
TR MR RS CS TD
9600 CD RD
2.6 V.33 Leased Line Operation (Quick
Setup 10)
V.33 operation is available on the
modem and is restricted to speeds
of 12,000 and 14,400 bps.
V.33 leased line operation
provides compatibility with V.33
modems (synchronous operation
only).