PCIE Pinout doubts and Problems Cyclone V

Hi,

The PRSNT#1 is the Present# signal for the PCIe. It should be connected to the farthest PRSNT#2 pin/signal depending on the lane width.

PERST# Signal

The PERST# signal is de-asserted to indicate when the system power sources are within their specified voltage tolerance and are stable.

PERST# should be used to initialize the card functions once power sources stabilize.

PERST# is asserted when power is switched off and also can be used by the system to force a hardware reset on the card.

System may use PERST# to cause a warm reset of the add-in card.

PERST# is asserted in advance of the power being switched off in a power-managed state like S3.

PERST# is asserted when the power supply is powered down, but without the advanced warning of the transition.

The REFCLKp/REFCLKn signals are used to assist the synchronization of the device’s card’s PCI Express interface timing circuits. Availability of the reference clock at the card interface may be gated by the CLKREQ# signal

When the reference clock is not available, it will be in the parked state. A parked state is when the clock is not being driven by a clock driver and both REFCLKp and REFCLKn are pulled to ground by the ground termination resistors

WAKE# signals should be connected to the other PCIe devices as this is used for link re-activation.