Synchronized Operation of Two NI 5911 Digitizer Boards with RTSI.
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This example allows you to operate two scopes to simultaneously sample two channels on both digitizers. One card is made the master and is set up to trigger on the incoming signal (analog triggering), and the slave board is set up to trigger off the digital trigger coming from the master signal (the master is set up to output a trigger over RTSI).
Unlike MIO boards, the update clock is not sent from master to slave. The technique used here to synchronize both digitizers is phase locked looping (PLL) . A 10 MHz clock is sent from master to slave to frequency lock both boards' clocks. For more information on this technique, turn to the user manual for the digitizer.
This example also allows you to compensate for the delay in passing the trigger from one board to the other. On the front panel in a control labeled delay between boards. To figure out what this should be set to, first run this program with it set to zero and the same exact waveform being fed into both boards. You should see on plot leading the other due to the delay and if you zoom in, you can figure out what this distance is. It should be in the nanosecond range.
Once you have determined this delay, enter this number into the control labeled delay between boards. You should now see that the plots are lined up and you are now ready to measure your own signal.
Filename: 202657.vi
Application Software: LabVIEW Full Development System 5.1.1
Language(s): LabVIEW
Hardware Group: High-Speed Digitizers (Scopes)
Driver: NI-SCOPE 1.6
Unlike MIO boards, the update clock is not sent from master to slave. The technique used here to synchronize both digitizers is phase locked looping (PLL) . A 10 MHz clock is sent from master to slave to frequency lock both boards' clocks. For more information on this technique, turn to the user manual for the digitizer.
This example also allows you to compensate for the delay in passing the trigger from one board to the other. On the front panel in a control labeled delay between boards. To figure out what this should be set to, first run this program with it set to zero and the same exact waveform being fed into both boards. You should see on plot leading the other due to the delay and if you zoom in, you can figure out what this distance is. It should be in the nanosecond range.
Once you have determined this delay, enter this number into the control labeled delay between boards. You should now see that the plots are lined up and you are now ready to measure your own signal.
Requirements
Filename: 202657.vi
Software Requirements
Application Software: LabVIEW Full Development System 5.1.1
Language(s): LabVIEW
Hardware Requirements
Hardware Group: High-Speed Digitizers (Scopes)
Driver: NI-SCOPE 1.6
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