Chapter2 HardwareOverview
©NationalInstruments Corporation 2-7 NI5620 User Manual
Figure2-4. Multiple-RecordAcquisition Timing Diagram

Triggering

Youcan extern ally trigger the NI 5620 through the digital line, PFI1. You
can also usesoftw are to triggerit. Figure2-5 shows the different trigger
sources.The digital triggersare TTL-level signals with a minimum
pulse-width requirement of 100 ns or 16 ns times the DDC decimation.
Figure2-5. DigitalTrigger Sources
Calibration
Althoughthe NI 5620is factory calibrated, it needs periodic calibration to
verifythat it is still within the specified accuracy. For more information o n
calibration, contact NI or visit the NI Web site at ni.com.
Trigger
Acquisition
InProgress
Buffer
=Trigger Not Accepted (Pretrigger Points Not Acquired)
=Trigger Not Accepted (500 ns Dead Time)
=Trigger Not Accepted (Acquisition in Progress)
=Trigger Accepted
12
1
1 2 3
2
3
500ns
Trigger
Software
RTSI<0..7>
PFI1
8
PXIStar