Av Mute; Audio Return Channel - Analog Devices ADV8003 Hardware Manual

6.13.4. AV Mute

AV mute can be enabled once HDCP authentication is completed between the ADV8003 and the downstream sink. This can be used to
maintain HDCP synchronization while changing video resolutions. While the KSVs for the downstream devices are being collected, an
active HDCP link capable of sending encrypted video is established, but video should not be sent across the link until the KSVs have been
compared with the revocation list.
It is not recommended to rely on AV mute to avoid sending audio and video during HDCP authentication. This is because AV mute does
not actually mute audio or video in the Tx. It requests the function from the sink device. The best way to avoid sending unauthorized
audio and video is to not send data to the Tx core of the ADV8003 until authentication between the ADV8003 and the downstream sink is
complete. Another option is to black out the video data input to the Tx core and disable the audio inputs to mute the audio. Refer to
Section 6.4 for an explanation of how to enable AV mute. Refer to Section
inputs.

6.14. AUDIO RETURN CHANNEL

The ADV8003 features an Audio Return Channel (ARC) Rx in each HDMI Tx that supports the extraction of an SPDIF stream from the
ARC component of an HDMI Ethernet and Audio Channel (HEAC) signal output by a downstream sink. The ADV8003 can process the
HEAC signal output by the downstream sink in only common mode.
The ARC Rxs are powered up by default but can be powered down using the
pins are disabled by default and must be manually enabled to configure the ADV8003 to output ARC audio. The pins can be manually
enabled by setting both arc_pins_oe_man
ARC1_OUT and ARC2_OUT pins.
tx1_arc_s_end_hpd and tx2_arc_s_end_hpd
or common-mode ARC is being received.
tx1_arc_powerdown, IO Map, Address 0x1A87[7]
This bit is used to powerdown the TX1 ARC block.
Function
tx1_arc_powerdown
0 
1
tx2_arc_powerdown, IO Map, Address 0x1A89[7]
This bit is used to powerdown the TX2 ARC block.
Function
tx2_arc_powerdown
0 
1
arc_pins_oe_man, IO Map, Address 0x1ACA[7]
This bit is used to control the output enable for ARC outputs.
Rev. B, August 2013
and arc_pins_oe_man_en
must both be left at the default value (1'b0) at all times – regardless of whether single-ended
Description
Power up ARC
Power down ARC
Description
Power up ARC
Power down ARC
6.11 for an explanation of how to disable the various audio
tx1_arc_powerdown
to 1. The SPDIF signal extracted by the ARC Rx can be output on the
290
ADV8003 Hardware Manual
and tx2_arc_powerdown bits. The ARC