ID:176188 Pin <name> driving clock input pin of fast PLL <name> does not have same I/O standard as other differential I/O pins driven by that PLL -- Fitter will automatically assign <name> differential I/O standard to pin

CAUSE: You assigned a different differential I/O standard to the specified pin driving the clock input pin of the specified fast PLL. However, the specified pin must have the same differential I/O standard as the other differential I/O pins driven by the fast PLL, including the clock input pin of the fast PLL. The Fitter will automatically assign the specified differential I/O standard to the pin.

ACTION: Change the I/O standard assignments so that all the differential I/O pins driven by the specified fast PLL, as well as the clock input pin of the fast PLL, have the same I/O standard.