Chapter 4 Signal Connections
VXI-MIO Series User Manual 4-4
National Instruments Corporation
SCANCLK DGND Output 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.
EXTSTROBE* DGND Output External Strobe—This output can be toggled under software
control to latch signals or trigger events on external devices.
PFI0/TRIG1 DGND Input
Output
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/TRIG2 DGND Input
Output
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* DGND Input
Output
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/GPCTR1_SOURCE DGND Input
Output
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/GPCTR1_GATE DGND Input
Output
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.
GPCTR1_OUT DGND Output Counter 1 Output—This output is from the general-purpose
counter 1 output.
Signal Name Reference Direction Description
(Continued)