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Chapter 4     Signal Connections
AT-MIO/AI E Series User Manual
4-34
 National Instruments Corporation
EXTSTROBE* signal.  A 10 
µ
s and a 1.2 
µ
s clock are available for 
generating a sequence of eight pulses in the hardware-strobe mode.  
Figure 4-16 shows the timing for the hardware-strobe mode 
EXTSTROBE* signal.  
Figure 4-16.  EXTSTROBE* Signal Timing
TRIG1 Signal
Any PFI pin can externally input the TRIG1 signal, which is available 
as an output on the PFI0/TRIG1 pin.  
Refer to Figures 4-13 and 4-14 for the relationship of TRIG1 to the data 
acquisition sequence.
As an input, the TRIG1 signal is configured in the edge-detection mode.  
You can select any PFI pin as the source for TRIG1 and configure the 
polarity selection for either rising or falling edge.  The selected edge of 
the TRIG1 signal starts the data acquisition sequence for both 
posttriggered and pretriggered acquisitions.  The AT-MIO-16E-1, 
AT-MIO-16E-2, AT-MIO-16XE-10, AT-AI-16XE-10, and 
AT-MIO-64E-3 support analog triggering on the PFI0/TRIG1 pin.  See 
Chapter 3 for more information on analog triggering.
As an output, the TRIG1 signal reflects the action that initiates a data 
acquisition sequence.  This is true even if the acquisition is being 
externally triggered by another PFI.  The output is an active high pulse 
with a pulse width of 50 to 100 ns.  This output is set to tri-state at 
startup.
Figures 4-17 and 4-18
 
show the input and output timing requirements 
for the TRIG1 signal.
t
w
t
w
V OH
V OL
t
w
= 600 ns or 5 
µ
s