AR# 70809

HDMI Receiver Subsystem v3.0 (Rev. 1) - Why do I see color shift issue when TX and RX PLLs are in bonded mode?

Description

When I test the HDMI example design with Apple TV 4K, the icon shifts towards the right side after I press "p".

When the icon cannot move towards the right anymore, a green screen appears.

The image below shows the icon position when the icon starts to shift:


 

After I press "p" twice, NETFLIX moves towards to the right side:


 

Then it turns to green after pressing "p" again:


What can cause this problem?



Solution

This is a known issue in the KC705 and ZC706 HDMI example design. 

When TX and RX are in bonded mode, some TX datapaths are still being re-initialized after attaining the GT TX RESETDONE state.

This issue will be fixed in Vivado 2018.1 and later versions.

In versions prior to 2018.1, users can work around the problem by moving the code below from RxStreamUpCallback to StartTxAfterRx API in the xhdmi_example.c.

// When the GT TX and RX are coupled, then start the TXPLL
if (XVphy_IsBonded(&Vphy, 0, XVPHY_CHANNEL_ID_CH1)){
// Start TX MMCM
XVphy_MmcmStart(&Vphy, 0, XVPHY_DIR_TX);
usleep(10000);
}

Linked Answer Records

Master Answer Records

AR# 70809
Date 07/06/2018
Status Active
Type General Article
IP