DisplayPort Intel® FPGA IP User Guide

ID 683273
Date 10/16/2023
Document Table of Contents Video Input Port

You must connect the clock recovery core video input port to the DisplayPort sink core video output image port.
Figure 9. Video Input Port Timing Diagram

When the PIXELS_PER_CLOCK parameter is greater than 1, all input pixels are supposed to be valid when you assert vidin_valid. The parameter only supports timings with horizontal active width divisible by 2 (PIXELS_PER_CLOCK = 2) or 4 (PIXELS_PER_CLOCK = 4).

The clock recovery core video output port produces pixel data with standard hsync, vsync, or de timing. All signals are synchronous to the reconstructed video clock rec_clk, unless mentioned otherwise. For designs using a TX transceiver, you can use rec_clk as its reference clock.

You can use rec_clk_x2 as a reference clock for transceivers that have reference clocks with frequencies lower than the minimum pixel clock frequency received. For example, the Video Graphics Array (VGA) 25-MHz resolution when the transceiver's minimum reference clock is 40 MHz.

The clock recovery core asserts reset_out when the remaining port signals are not valid. For example, during a recovered video resolution change when the rec_clk and rec_clk_x2 signals are not yet locked and stable. Intel recommends that you use reset_out to reset the downstream logic connected to the video output port.

During the hardware demonstration operation, you can adjust the DisplayPort source resolution (graphics card) from the PC and observe the effect on the IP core. The Nios II software prints the source and sink AUX channel activity. Press one of the push buttons to print the current TX and RX MSA.