Chapter 3
– 23 –
PCI-1711/1731 User’s Manual
Advantech Co., Ltd.
www.advantech.com
+7 V D/A output.
Figure 3-3 shows how to make analog output and external reference
input connections on the PCI-1711.
Fig. 3-3 Analog output connections
3.5 Trigger Source Connections
Internal Pacer Trigger Connection
The PCI-1711 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 outputing 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_OUT) will trigger an A/D conversion on the
PCI-1711/1731. 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 PCI-1711/1731 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
+
+
_
_
I/O Connector
External Reference
For DA
0
Signal
External Reference
For DA
1
Signal
External
DA0
DA1
Load
Load
DA0_REF
DA1_REF
DA1_OUT
DA0_OUT
AOGND
INT_REF
INT_REF
DATA BUS
-5V
-10V
Internal
