Editing Eye pattern (section)

==== Clock recovery ====

Most high speed serial signals, such as [[PCIe]], [[DisplayPort]], and most variants of [[Ethernet]], use a [[line code]] which is intended to allow easy [[clock recovery]] by means of a [[Phase-locked loop|PLL]]. Since this is how the actual receiver works, the most accurate way to slice data for the eye pattern is to implement a PLL with the same characteristics in software. Correct PLL configuration allows for the eye to conceal the effects of spread spectrum clocking and other long-term variation in the symbol rate which do not contribute to errors at the receiver, while still displaying higher frequency jitter.