Larson Davis System 824, Справочное руководство

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11/8/00 Using ID Setting Files 7-11
AC/DC Output Settings - (SSA,
LOG, ISM)
The AC/DC Output on the 824 allows the user to select what
type of signal will be sent out the 3.5mm connector at the
base of the instrument. See page 5-4 for more details.
Logic Input Setting - (SSA,
LOG, ISM)
The SSA instrument can access the
Logic-input Mode setting through
either the Check or the Setup menus. The Logic Input sets the functionality of the logic input pin
on the control connector (pin 3). This pin is intended to be
connected to an external switching device—possibly a push-
button switch. The external switching device will either con-
nect the pin to +5 V (pin 6) or unconnected. This signal may
also be supplied from another device that can supply a 0 to
+5 volt logic signal (input load impedance is 100K ohms).
The resulting logical state (high or low) will determine what
occurs inside the instrument as a function of this Logic
Input setting. Accordingly, the setting provides the follow-
ing five options:
None - The state of the logic input pin has no
effect.
Pause - Whenever the logic input is connected to
+5V (e.g. when a push-button switch makes con-
tact), the instrument pauses when in the run mode.
Toggle - Each time the logic input is connected to
+5V, (e.g. switch makes contact) the instrument
runs or stops. The effect is the same as pressing
the
Run/Stop key.
Caution: The Level setting overrides
the RUN/STOP key and I/O Run/
Stop function commands. Level - When the logic input is connected to +5V,
(e.g. switch makes contact) the instrument runs.
When the logic input is disconnected from +5V
(e.g. switch breaks contact), the instrument stops.
Alarm - When the logic input is connected to +5V
(e.g. switch makes contact), the instrument ini-
tiates a dial-out sequence. This option is intended
for use only with advanced remote monitoring
applications where the instrument is paired with a
modem.
Logic Output Setting - (SSA,
LOG, ISM)
The Logic Output (2 outputs are available) selects the func-
tionality of the logic output pin on the control connector
(pin 2 referenced to ground, which is on pin 1) and the