Can we lock 80 MHz timebase to PXI_CLK10 on PXI-6220 M Series DAQ?

Question

I am using PXI-6220 to measure Frequency/Period of 32768 Hz clock signal, accuracy is very important. I have provided signal to measure on Gate input of Ctr 0 (PFI 9). I am using 80 Mhz Timebase. I want to Lock PLL to PXI back plane 10 MHz reference (PXI_CLK10) which in turn is locked onto the 10 MHz reference via PXI-5600 on Slot 2 (External 10 Mhz standard is connected). so far I don't see a way to lock PLL to PXI_CLK10. Is that possible at all? see the image attached to this message.
Attachments:
M Series DAQ Question.png ‏62 KB

Answer 1

Hello Abhatti,
Based on the diagram that you have attached, the M-Series card can PLL to a higher accuracy clock such as the PXI Clock_10.  The way to configure this change using the DAQmx driver is route the signals using the DAQmx Timing RefClk.Src Timing property node.  Once you place down this property node, and specify the RefClk.Src attribute, you select the PXI-Clk10 as your reference clock source.  This will discipline the 80 MHz Timebase of the DAQ card to the 10 MHz reference clock of the PXI chassis.  Which chassis are you using?  Also, how have you PLL'ed the 10 MHz backplane clock to the PXI-5600 Downconverter?
Michael L.
Applications Engineer
National Instruments