Black Box 32144, Manual

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MODEM 32144
DTR from EIA
All modes
This option allows the user to
force the Data Terminal Ready
(DTR) signal on (TRUE), which
may be needed if your computer or
communication software does not
supply a DTR signal.
NORMAL. DTR is supplied by
the DTE. When DTR goes low, the
modem sends a space disconnect
(if TX Space Disconnect is
enabled) and goes on-hook.
TRUE. The DTR signal is
internally forced ON regardless
of the DTR status at the interface.
DTE Control of ALB (ALB- DTE
Ctrl’ed)
All modes
Analog loopback (ALB) testing
can be initiated from the DTE via
pin 18. Positive voltage activates
the test, whereas negative voltage
results in normal operation.
Disabling this option keeps the
modem from responding to pin 18.
DTE Control of RDL (RDL- DTE
Ctrl’ed)
All modes
Remote digital loopback (RDL)
testing can be initiated from the
DTE via pin 21. Positive voltage
activates the test, whereas negative
voltage results in normal operation.
Disabling this option keeps the
modem from responding to pin 21.
Test Mode (TM to EIA)
All modes
This option controls pin 25, the
test mode (TM) indicator, on the
RS-232 interface connector.
NORMAL. TM output is high
(active) only during test modes.
TRUE. TM output is high all of
the time.
3.14 Modem Setups
The options listed below, through
RTS-CTS Delay, are available via
the MODEM SETUPS screens.
Carrier Detect
All modes
This option selects the carrier
detect level. To make a selection,
first select either LEASED or DIAL
from the CARRIER DET. LVL
screen, depending on your
application. The appropriate
carrier detect level screen will
then be displayed.
Leased-Line Applications
For leased-line use, the carrier
detect level can be set for –43, –33
or –26 dBm. The default setting is
–26 dBm.