R-Tile Avalon® Streaming Intel® FPGA IP for PCI Express* User Guide

ID 683501
Date 4/10/2024
Document Table of Contents

6.3. Signal Tap Logic Analyzer

You can use the Signal Tap Logic Analyzer to monitor the top-level signals below from the R-Tile Avalon-ST IP for PCIe as an additional debug tool for PCIe issues.

Table 111.  Top-Level Signals to be Monitored for Debug Purposes
Signal Description Expected Value for Successful Link-up

A "1" on this active-low signal indicates that the FPGA device is not yet fully configured. A "0" indicates the device has been configured and is in normal operating mode. You need to instantiate the Reset Release IP and connect the output of that IP to ninit_done.

pin_perst_n_o This output signal to the FPGA fabric indicates if PERST# is asserted. 1'b1

This active-low signal is held low until pin_perst_n has been deasserted and the PCIe Hard IP has come out of reset.

This signal is synchronous to coreclkout_hip. Traffic between the user logic in the FPGA core and the IP can start when pX_reset_status_n_o is asserted high.

pX_link_up_o When asserted, this signal indicates the link is up at the Physical Layer. 1'b1
pX_dl_up_o When asserted, this signal indicates the Data link (DL) Layer is active. 1'b1
pX_ltssm_state_delay_o[5:0] Indicates the LTSSM state. Note that there is a time difference between the actual link state at the physical level and the time it takes to reflect its value on this signal. 6'h11 (L0)