AnsweredAssumed Answered

ADV7842KBCZ-5 encryption issue

Question asked by Alberto on Oct 13, 2015
Latest reply on Oct 16, 2015 by mattp



One of my customers is using the ADV7842KBCZ-5 (ADV7842 with HDCP support). The
customer has this device in several equipments. In some of them customer has to
disable the HDCP keys. To do this, the customer is following some of the
advices posted in the Engineer zone (see in bold below):

- The source decides if it encrypts or not. The receiver doesn't get a
choice. What you can do is use the HDCP_A0 bit to make the keys inaccessible in
ADV7842 so authentication will fail when the TX tries. What happens after that
is up to the source--- send unencrypted or send nothing.

There are several threads about this if you search:

Customer HW is set by default with the HDCP disabled, and until know it looked
that everything was working properly. But now some end-customers are
complaining that in some occasions, when connecting some video HDMI sources
(like appleTV) to my customer HW with HDCP disabled, these sources activate the
HDCP encryption even when the video content is free. This makes that my customer HW
does not connect to the HDMI source. Customer is doing some tests with the
ADV7842KBCZ-5P (without HDCP) and the HDCP encryption is no activated with this
device and everything works fine.

The question is : Is there any way to program the ADV7842KBCZ-5 so that it
works like ADV7842KBCZ-5P and does not activate the HDCP encryption?

In the Engineer Zone only suggests the solution already implemented for the
customer and is not working properly in some cases

Thanks in advance