Transmit – Main Link Problem After Training - 2.1 English - PG199

DisplayPort 1.2 TX Subsystem LogiCORE IP Product Guide (PG199)

Document ID
PG199
Release Date
2024-12-11
Version
2.1 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.

  • Perform a software reset on the register 0x01C and check if the video is proper now.
  • Check if the MAIN_STREAM_ENABLE register is set to 1.
  • Ensure that the MSA parameters match the Video being sent by the TX.
  • Check the video pixel clock generation. Ensure that the Video Clock is based on the resolution being sent.
  • Dump the DisplayPort source registers and compare against a working log.
  • Check the symbol and disparity errors in the Sink through DPCD registers. This could be due to cable issue or PHY (GT) alignment issue.
  • Make sure the transceiver lane LOC pin assignment is correct and no lane swapping is present.