SLLA611 september   2023 TDP1204

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2TDP1204 Controls for HDMI Compliance Testing
    1. 2.1 Adjusting Equalization for the Short Cable Model
    2. 2.2 Adjusting Equalization for the Worst Cable Model
    3. 2.3 Adjusting Differential Output Swing
    4. 2.4 Adjusting Termination
  6. 3Transmitter Emphasis Control
  7. 4Summary
  8. 5References

Transmitter Emphasis Control

The TDP1204 supports both linear and limited redriver modes. However, the transmitter pre-emphasis and de-emphasis control is only supported in limited mode for HDMI 1.4 or HDMI 2.0. When the TDP1204 is operating as an HDMI 2.1 redriver pre-emphasis implementation is not available and only the de-emphasis is modified by the device based upon the DDC TXFFE snooped value. Since the pre-emphasis implementation is not available when operating as an HDMI 2.1 redriver, care must be taken while running HDMI 2.1 compliance testing to make sure that the pre-emphasis tests are not inadvertently selected. Therefore, running the pre-emphasis tests while using TDP1204 as an HDMI 2.1 redriver causes HDMI 2.1 compliance testing to report failures.