Chapter4 SignalConnections
©NationalInstruments Corporation 4-5 6023E/6024E/6025EUser Manual
SCANCLK DGND Output scanclock—this pin pulses once for each A/D conversion
inscanning mode when enabled. The low-to-high edge
indicateswhen the input signal can be removed from the
inputor switched to another signal.
EXTSTROBE* DGND Output Externalstrobe—you can toggle this output under software
controlto latch signals or trigger events on external devices.
PFI0/TRIG1 DGND Input
Output
PFI0/Trigger1—as an input, this is one of the
programmablefunction inputs (PFIs). PFI signals are
explainedin the Timing Connections sectioninthischapter.
Asan output, this is the TRIG1 (AI start trigger) signal.
Inposttrigger data acquisition sequences, a low-to-high
transitionindicates the initiation of the acquisition
sequence.In pretrigger applications, a low-to-high
transitionindicates the initiation of the pretrigger
conversions.
PFI1/TRIG2 DGND Input
Output
PFI1/Trigger2—as an input, this is one of the PFIs.
Asan output, this is the TRIG2 (AI stop trigger) signal. In
pretriggerapplications, a low-to-high transition indicates
theinitiation of the posttrigger conversions. TRIG2 is not
usedin posttrigger applications.
PFI2/CONVERT* DGND Input
Output
PFI2/Convert—asan input, this is one of the PFIs.
Asan output, this is the CONVERT* (AI convert) signal.
Ahigh-to-low edge on CONVERT* indicates that an A/D
conversionis occurring.
PFI3/GPCTR1_SOURCE DGND Input
Output
PFI3/Counter1 Source—as an input, this is one of the PFIs.
Asan output, this is the GPCTR1_SOURCE signal. This
signalreflects the actual source connected to the
general-purposecount er 1.
PFI4/GPCTR1_GATE DGND Input
Output
PFI4/Counter1 Gate—as an input, this is one of the PFIs.
Asan output, this is the GPCTR1_GATE signal. This signal
reflectsthe actual gate signal connected to the
general-purposecount er 1.
GPCTR1_OUT DGND Output Counter1 Output—this output is from the general-purpose
counter1 output.
Table4-2. I/OConnector Signal Descriptions (Continued)
SignalName Reference Direction Description