Chapter4 SignalConnections
6023E/6024E/6025EUser Manual 4-34 ni.com
Figure4-20. EXTSTROBE*Signal Timing
TRIG1 Signal
Any PFIpin can externally input the TRIG1 signal, which is available as
an output on the PFI0/TRIG1 pin.
Refert o Figures 4-17 and 4-18 for the relationship of TRIG1 to the DAQ
sequence.
As aninput, the TRIG1 signal is configured in the edge-detection mode.
Youcan select any PFI pin as the source for TRIG1 and configure the
polarityselection for either rising or falling edge. The selected edge of the
TRIG1 signal starts the data acquisition sequence for both posttriggered
and pretriggered acquisitions.
As anoutput, the TRIG1 signal reflects the action that initiates a DAQ
sequence. This is true evenif the acquisition is externally triggered by
another PFI. The output is an activehigh pulse with a pulsewidth of
50to 100 ns. This output is set to high impedance at startup.
Figures 4-21 and 4-22 show the input and output timing requirements for
the TRIG1 signal.
Figure4-21. TRIG1Input Signal Timing
twtw
VOH
VOL
tw=600nsor5ยตs
Rising-Edge
Polarity
Falling-Edge
Polarity
tw
tw=10 ns minimum