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PXI STAR Trigger
When PXI STAR is selected as the trigger source, the PXIe-69529 accepts a TTL-compatible
digital signal as a trigger signal. The trigger occurs when a rising edge or falling edge is
detected at PXI STAR, with trigger polarity configurable by software, with minimum pulse
width requirement of the digital trigger signal 300 ns.
PXIe_DSTARB Trigger
The PXIe_DSTARB signal, a differential signal transmitted via the PXI Express Chassis
backplane, distributes high-speed, high-quality trigger signals. When PXIe_DSTARB is
selected as the trigger source, the PXIe-69529 accepts a fast-switching LVDS digital signal
as a trigger signal. Triggering occurs when a rising edge or falling edge is detected at
PXIe_DSTARB, with trigger polarity configurable by software, with minimum pulse width
requirement 300 ns.
PXI Trigger Bus
The PXIe-69529 utilizes PXI Trigger Bus Numbers 0 through 7 to act as a System
Synchronization Interface (SSI). With the interconnected bus provided by PXI Trigger Bus,
multiple modules are easily synced. When configured as input, the PXIe-69529 serves as a
slave module and can accept trigger signals from one of buses 0 through 7. When configured
as output, the PXIe-69529 serves as a master module and can output trigger signals to the
PXI Trigger Bus Numbers 0 through 7.
Analog Trigger
The PXIe-69529 analog trigger circuitry can be configured to monitor one analog input
channel from which data is acquired. Selection of an analog input channel as the analog
trigger channel does not influence the input channel acquisition operation. The analog
trigger circuit generates an internal digital trigger signal based on the condition between
the analog signal and the defined trigger level.
Analog trigger conditions are as follows:
• Positive-slope trigger: The trigger event occurs when the analog input signal changes
from a voltage lower than the specified trigger level to a voltage exceeding the
specified trigger level.
• Negative-slope trigger: The trigger event occurs when the analog input signal
changes from a voltage exceeding the specified trigger level to a voltage lower than
the specified trigger level.
