NI DAQ 6052E, Руководство пользователя

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Chapter 4 Connecting the Signals
© National Instruments Corporation 4-29 NI 6052E User Manual
decrements to zero, it is loaded with the number of posttrigger scans to
acquire while the acquisition continues. The device ignores TRIG2 if it is
asserted prior to the SC decrementing to zero. After the selected edge of
TRIG2 is received, the device acquires a fixed number of scans and the
acquisition stops. In pretriggered mode, the device acquires data both
before and after receiving TRIG2.
As an output, TRIG2 reflects the posttrigger in a pretriggered sequence,
even if the acquisition is externally triggered by another PFI. TRIG2 is not
used in posttriggered data acquisition. The output is an active high pulse
with a pulse width of 50 to 100 ns. This output is set to high-impedance at
startup.
Figures 4-19 and 4-20 show the input and output timing requirements
for TRIG2.
Figure 4-19. TRIG2 Input Signal Timing
Figure 4-20. TRIG2 Output Signal Timing
Rising-Edge
Polarity
Falling-Edge
Polarity
t
w
= 10 ns minimum
t
w
t
w
= 50 to 100 ns
t
w