National Instruments VXI-MIO Series User Manual page 50

Chapter 4 Signal Connections
Signal Name
SCANCLK
EXTSTROBE*
PFI0/TRIG1
PFI1/TRIG2
PFI2/CONVERT*
PFI3/GPCTR1_SOURCE
PFI4/GPCTR1_GATE
GPCTR1_OUT
VXI-MIO Series User Manual
Reference Direction
DGND Output
DGND Output
DGND Input
Output
DGND Input
Output
DGND Input
Output
DGND Input
Output
DGND Input
Output
DGND Output
Description (Continued)
Scan Clock—This pin pulses once for each A/D conversion
in the scanning modes when enabled. The low-to-high edge
indicates when the input signal can be removed from the
input or switched to another signal.
External Strobe—This output can be toggled under software
control to latch signals or trigger events on external devices.
PFI0/Trigger 1—As an input, this is either one of the PFIs or
the source for the hardware analog trigger. PFI signals are
explained in the Timing Connections section later in this
chapter. The hardware analog trigger is explained in the
Analog Trigger section in Chapter 2.
As an output, this is the TRIG1 signal. In posttrigger data
acquisition sequences, a low-to-high transition indicates the
initiation of the acquisition sequence. In pretrigger
applications, a low-to-high transition indicates the initiation
of the pretrigger conversions.
PFI1/Trigger 2—As an input, this is one of the PFIs.
As an output, this is the TRIG2 signal. In pretrigger
applications, a low-to-high transition indicates the initiation
of the posttrigger conversions. TRIG2 is not used in
posttrigger applications.
PFI2/Convert—As an input, this is one of the PFIs.
As an output, this is the CONVERT* signal. A high-to-low
edge on CONVERT* indicates that an A/D conversion is
occurring.
PFI3/Counter 1 Source—As an input, this is one of the
PFIs.
As an output, this is the GPCTR1_SOURCE signal. This
signal reflects the actual source connected to the
general-purpose counter 1.
PFI4/Counter 1 Gate—As an input, this is one of the PFIs.
As an output, this is the GPCTR1_GATE signal. This signal
reflects the actual gate signal connected to the
general-purpose counter 1.
Counter 1 Output—This output is from the general-purpose
counter 1 output.
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