Connecting an external oscillator

Question

Hi all,

I saw that previously in this forum, someone asked if you could connect an external clock to the ZedBoard, and the responses confirmed that you could. However, I'm in the process of doing so now, and the only inputs I see available are on the FEC connector. Is there a way to connect a standalone oscillator?

Thanks!
Joanna

drozwood90 · Accepted Answer

Hi there,

On a ZedBoard, you can connect an external oscillator through the FMC connector as well as one of the PMOD connectors. Both have clock capable pins.
You can reference section 2.5 Clock sources in the ZedBoard Hardware Users Guide.

This is also referenced in this post:
http://zedboard.org/content/use-external-clock-signal-zedboard

Details from the guide are listed there.

The Zynq PLLs can easily generate most clocks without issue, using only the provided Oscillators on the ZedBoard. This means you should be able to use the PL side of the Zynq to pass a clock out to other hardware.

Please also reference this post:
http://zedboard.org/content/zedboard-fmc-external-clock

It offers two other solutions. If you choose to use a pin compatible part, replacing one of the provided oscillators, you do this at your own risk. We do not warranty boards for rework gone awry.

Can you tell me what you are trying to accomplish? I might be able to help you with the a better solution.

--Dan