divide the internal sample clock (VCXO)

Hi all

I want to divide clock source internal sample of my high-speed 5122 digitizer PXI card.

5122 PXI, 200 MHz internal clcok source example. I want to taste my data at 10 MHz.

So I want to divide down the clock of internal sampling by a factor of 20.

I want to do it programmatically.

I have found no vi node or property for that (although found the node property for entry divider OR worn... but which has been used only for reference for on-board clock clock)

Help me as soon as possible...

Hi Jirav,

I just wanted to clear some things. The 5122 has a sampling rate 100 MECH's maximum real-time. / s (not 200 MHz as you originally suggested). To obtain a rate of 10 MHz, you would be divided down by a factor of 10. From page 13 of the document specifications NI 5122:

Just to add to what Henrik suggested, the following help topic describes the specific VI to configure horizontal properties such as the sampling frequency, he mentioned:

http://zone.NI.com/reference/en-XX/help/370592P-01/scopeviref/niscope_configure_horizontal_timing/

Most of the expedition OR SCOPE examples use the VI above and there is an entry for "min sampling rate" where you can simply specify the value "10 M" or '10000000' to get the device of sampling at a lower rate.

Note: because the digitizer allows only sampling frequencies which are an integer divide down the maximum sampling frequency, rate will always be forced to match up to the second tier legal sample. For example, if you specify '9.8435 M', it would automatically force the rate up to 10 MHz. To display the actual value that the scanner is used, you can query the property node "Actual sampling frequency" at any point in your code after the configurations have been committed digitizer. The help manual describes this property on the following page:

http://zone.NI.com/reference/en-XX/help/370592N-01/scopepropref/pniscope_actualsamplerate/

Kind regards

Tags: NI Products

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