National Instruments 3.21E+04 Benutzerhandbuch
Chapter 3 Hardware Overview
AT-MIO/AI E Series User Manual
3-16
National Instruments Corporation
shown in Figure 3-8. The trigger-level range for the direct analog
channel is
channel is
±
10 V in 78 mV steps for the AT-MIO-16E-1,
AT-MIO-16E-2, and AT-MIO-64E-3, and
±
10 V in 4.9 mV steps
for the AT-MIO-16XE-10 and AT-AI-16XE-10. The range for the
post-PGIA trigger selection is simply the full-scale range of the
selected channel, and the resolution is that range divided by 256 for
the AT-MIO-16E-1, AT-MIO-16E-2, and AT-MIO-64E-3, and
divided by 4,096 for the AT-MIO-16XE-10 and AT-AI-16XE-10.
post-PGIA trigger selection is simply the full-scale range of the
selected channel, and the resolution is that range divided by 256 for
the AT-MIO-16E-1, AT-MIO-16E-2, and AT-MIO-64E-3, and
divided by 4,096 for the AT-MIO-16XE-10 and AT-AI-16XE-10.
Note:
The PFI0/TRIG1 pin is a high-impedance input. Therefore, it is
susceptible to cross-talk from adjacent pins, which can result in false
triggering when the pin is left unconnected. To avoid false triggering, make
sure this pin is connected to a low-impedance signal source (less than
10 k
susceptible to cross-talk from adjacent pins, which can result in false
triggering when the pin is left unconnected. To avoid false triggering, make
sure this pin is connected to a low-impedance signal source (less than
10 k
Ω
source impedance) if you plan to enable this input via software.
Figure 3-8. Analog Trigger Block Diagram
There are five analog triggering modes available, as shown in
Figures 3-9 through 3-13. You can set lowValue and highValue
independently in software.
Figures 3-9 through 3-13. You can set lowValue and highValue
independently in software.
In below-low-level analog triggering mode, the trigger is generated
when the signal value is less than lowValue. HighValue is unused.
when the signal value is less than lowValue. HighValue is unused.
Analog
Input
Channels
Input
Channels
PFI0/TRIG1
PGIA
+
-
ADC
DAQ-STC
Analog
Trigger
Circuit
Trigger
Circuit
Mux