FPGA FlexIO: how can I get 250Mhz clock from 40Mhz clock on board pxi-7954?

[poiyyyy]

Hi!

I hope to get 250Mhz clock from 40Mhz clock on Pxi-7954.
I need 250Mhz clock with 0 phase/90 phase/180 phase /270 phase.
I don't how to do....

[Christian Mergl]

You can generate a derived Clock by right-clicking the "40MHz Onboard Clock" in your project and select "New FPGA derived Clock".

Christian

[poiyyyy]

Thank you!

I need four phase clock with 0 degree,90  degree,180degree,270degree.

use  clip ,I can  get  it, but  compiled error.

[Christian Mergl]

To have a 250MHz clock with 90/180/270/360 degree phase shift, you would need a 1GHz clock (4 times faster) to add the necessary delay to each of the clocks.

This is not possible with this hardware.

Christian

[RyanB]

You'll have to instantiate a PLL in a CLIP to get the 4 different phases of the 250 MHz clock.  You can instantiate this manually or use the Xilinx coregen GUI.

-RB