Chapter 4
Connecting the Signals
4-28
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Figures 4-17 and 4-18 show the input and output timing requirements
for TRIG1.
Figure 4-17.
TRIG1 Input Signal Timing
Figure 4-18.
TRIG1 Output Signal Timing
The device also uses TRIG1 to initiate pretriggered operations. In
pretriggered applications, TRIG1 is generated by a software trigger unless
a PFI pin is selected as the source of TRIG1. Refer to the
section for a complete description of the use of TRIG1 and TRIG2 in a
pretriggered operation.
TRIG2 Signal
Any PFI pin can externally input the TRIG2 signal, which is available as
an output on the PFI1/TRIG2 pin. Refer to Figure 4-16 for the relationship
of TRIG2 to the sequence.
As an input, TRIG2 is configured in edge-detection mode. You can select
any PFI pin as the source for TRIG2 and configure the polarity selection for
either rising or falling edge. The selected edge of TRIG2 initiates the
posttriggered phase of a pretriggered sequence. In pretriggered mode, the
TRIG1 signal initiates the acquisition. The scan counter (SC) indicates the
minimum number of scans before TRIG2 is recognized. After the SC
Rising-Edge
Polarity
Falling-Edge
Polarity
t
w
= 10 ns minimum
t
w
t
w
= 50 to 100 ns
t
w
