Chapter 4
Signal Connections
PCI-4451/4452/4453/4454 User Manual
4-10
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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.
UPDATE*
DGND
Output
A high-to-low edge on UPDATE* indicates that a D/A
conversion is occurring.
In LabVIEW, referred to as AO Update.
GPCTR1_OUT
DGND
Output
General-Purpose Counter 1 Output
PFI6/WFTRIG
DGND
Input
Output
PFI6/Waveform Trigger—As an input, this is one of the PFIs.
As an output, this is the WFTRIG signal. In timed analog
output sequences, a low-to-high transition indicates the
initiation of the waveform generation.
In LabVIEW, referred to as AO Start Trigger for both input
and output.
PFI7
DGND
Input
PFI7—This is one of the PFIs.
PFI8/GPCTR0_SOURCE
DGND
Input
Output
PFI8/Counter 0 Source—As an input, this is one of the
PFIs.
As an output, this is the GPCTR0_SOURCE signal. This
signal reflects the actual source connected to the
general-purpose counter 0.
PFI9/GPCTR0_GATE
DGND
Input
Output
PFI9/Counter 0 Gate—As an input, this is one of the PFIs.
As an output, this is the GPCTR0_GATE signal. This signal
reflects the actual GATE signal connected to the
general-purpose counter 0.
GPCTR0_OUT
DGND
Output
General-Purpose Counter 0 Output
FREQ_OUT
DGND
Output
Frequency Output—This output is from the frequency
generator output.
Table 4-5.
Digital I/O Connector Pin Assignment (Continued)
Signal Name
Reference
Direction
Description
