Transmit – Main Link Problem After Training - 3.0 English

DisplayPort 1.4 TX Subsystem Product Guide (PG299)

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3.0 English

This section contains debugging steps if the monitor is not displaying video even after a successful training or if the monitor display is noisy and has many errors.

  1. Perform a software reset on the register (0x01C) and check if the video is correct now.
  2. Check if the MAIN_STREAM_ENABLE register is set to 1.
  3. Ensure that the MSA parameters match the Video being sent by TX.
  4. Check the video pixel clock generation. Ensure that the Video Clock is based on the resolution being sent.
  5. Dump the DisplayPort source registers and compare against a working log.
  6. Check the symbol and disparity errors in the Sink through the DPCD registers. This could be due to cable issue or PHY (GT) alignment issue.
  7. Compare the design against the applicable example design.
  8. Use the example design with a Xilinx development board to test the physical setup.