Digital I/O

Showing results for 
Search instead for 
Did you mean: 

accessing the internal clock of PCle 6738 through PCIe interface


I want to access the internal clock of the PCIe 6738 through the PCIe interface by an Application Program. Also this internal clock should not comes through the OS( that is without relying on Os).

How to achieve this. Is it possible?




0 Kudos
Message 1 of 5

What do you mean by access? Why do you need this clock?

Soliton Technologies

New to the forum? Please read community guidelines and how to ask smart questions

Only two ways to appreciate someone who spent their free time to reply/answer your question - give them Kudos or mark their reply as the answer/solution.

Finding it hard to source NI hardware? Try NI Trading Post
0 Kudos
Message 2 of 5


I want to use  the internal  clock pulse from the NI card on the Application Program. Lets us say that the  Application program uses this internal clock to run certain counters or to implement certain delay. The Application Program needs this internal clock through the PCIe interface and not through the I/O channels. Is it possible to achieve the above requirement. If so kindly help me to implement this.






0 Kudos
Message 3 of 5

The clock itself does not pass through the PCIe interface.  But you have counters on your 6738 that can interact directly with the clock and then deliver *data* across the PCIe interface to your app.  That's probably what you should be planning to do instead, unless the time tracking and delay features built into your app programming language are already sufficient.



-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
0 Kudos
Message 4 of 5

PCIe is clocked by the Mainboard..


The 6738 provide 8 PFI channel to external  and 8 RTSI channel internal (on a board connector inside the PC) where a number of sync/trigger/clock signals can be routed. If you want to sync to other hardware  you will need extra cables in a PCI system. PXI systems provide dedicated extra lines.


As Kevin wrote you can initiate PCI activity within a certain timing on the 6738 and your OS and SW migth be within your needed loop time ...

BTW .. wich decade of a second you need to meet?

Greetings from Germany

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'

0 Kudos
Message 5 of 5