Black Box 32144, Руководство пользователя

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CHAPTER 3: Options: Customizing the Modem Setup
Fig. 3-3. Current Speed Type Selection.
Both connected modems must
be set for 208A/B operation. For
2-wire applications, the carrier
option must be set for switched
carrier operation (SWITCH) via
the CARRIER screen, and CTS
must be set to follow RTS (CTS
to EIA option).
V.29. This selection is available
only on models that include the
V.29/V.27/V.26 option. It
configures the modem for V.29
operation (for data rates of 9600,
7200, or 4800 bps). To select a
specific data rate, use the Speed
Limit option to select 9600, 7200,
or 4800 bps (only) as the minimum
and/or maximum data rate (DCE
RATE). In V.29 mode, the modem
does not support automatic rate
adjustment (fallback) or error
correction.
V.32
. The modem normally uses
the V.32 handshake. (The modem
also uses this handshake for
V.32/14.4 Kbps operation.)
V.33 operation is available on
the modem for 4-wire leased-line
synchronous operation only. The
available data rates are 14.4 and
12.0 Kbps. Either of these rates
may be set as the maximum or
minimum by using the Speed Limit
MAXIMUM RATE and MINIMUM
RATE screens.
Both connected modems must be
set for V.33 leased line operation.
208 . This selection (available only
on models that support Bell 208
operation) provides Bell 208A
compatibility for 2-wire or 4-wire
leased line operation and Bell 208B
compatibility for 2-wire dial
operation. Operation is full duplex
in 4-wire leased line mode only. In
Bell 208B mode, synchronous V.25
bis autodialing is available, but
Hayes operation is not. Calls may
be originated from the front panel.
The data rate is fixed at 4800 bps
for 208A/B operation, and the data
format is synchronous only.
SPEED TYPE V.32
DEC INC