GTY and GTM channels and clocks map from device to device as shown in This Figure, This Figure, This Figure, and This Figure. Key design items to note about GTY/GTM reference clocks are:
•Reference clock rates between 25G and 50G are not identical
°Assume a different clock is necessary at 50G
•RefClk0 must always be used
•RefClk1 migrates to NC on VU27P/VU29P
•Reference clocks should not be shared across GTM duals
•Reference clocks should not be shared across GTY Quads
•Provide local reference clocks to each GTY Quad that is migrated into a GTM Quad
