Advantech MIC-3716, Руководство пользователя

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3.5 Trigger Source Connections
Internal Pacer Trigger Connection
The MIC-3716 includes one 82C54 compatible programmable
Timer/Counter chip which provides three 16-bit counters connected to
a 10 MHz clock, each designated specifically as Counter 0, Counter 1
and Counter 2. Counter 0 is a counter which counts events from an
input channel or output pulse. Counter 1 and Counter 2 are cascaded
to create a 32-bit timer for pacer triggering. A low-to-high edge from
the Counter 2 output (PACER_OU T) will trigger an A/D conversion
on the MIC-3716. At the same time, you can also use this signal as a
synchronous signal for other applications.
External Trigger Source Connection
In addition to pacer triggering, the MIC-3716 also allows external
triggering for A/D conversions. When a +5 V source is connected to
TRG_GATE , the external trigger function is enabled. A low-to-high
edge coming from EXT_TRG will trigger an A/D conversion on the
MIC-3716. When DGND is connected to TRG_GAT E, the external
trigger function is thereby disabled.
3.6 Field Wiring Considerations
When you use the MIC-3716 to acquire data from outside, noises in
the environment might significantly affect the accuracy of your
measurements if cautions are not taken. The following measures will
help reduce possible interference running signal wires between signal