ADV8005 Hardware Reference Manual
UG-707
6.13.4.
AV Mute
AV mute can be enabled once HDCP authentication is completed between the
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
until authentication between the
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
explanation of how to enable AV mute. Refer to Section
for an explanation of how to disable the various audio inputs.
6.14.
AUDIO RETURN CHANNEL
The
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
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
and
are disabled by default and must be manually enabled to configure the
to output ARC audio. The pins can be manually enabled by
setting both
to 1. The SPDIF signal extracted by the ARC Rx can be output on the ARC1_OUT and
ARC2_OUT pins.
tx1_arc_s_end_hpd
and
tx2_arc_s_end_hpd
must both be left at the default value (1’b0) at all times – regardless of whether single-ended 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
Description
0 (default)
Power up ARC
1
Power down ARC
tx2_arc_powerdown
, IO Map,
Address 0x1A89[7]
This bit is used to powerdown the TX2 ARC block.
Function
tx2_arc_powerdown
Description
0 (default)
Power up ARC
1
Power down ARC
arc_pins_oe_man
, IO Map,
Address 0x1ACA[7]
This bit is used to control the output enable for ARC outputs.
Function
arc_pins_oe_man
Description
0 (default)
Input
1
Output
arc_pins_oe_man_en
, IO Map,
Address 0x1ACB[7]
This bit is used to control the manual override for ARC outputs.
Function
arc_pins_oe_man_en
Description
0 (default)
Auto
1
Manual override
To increase the noise immunity of the
ARC Rxs, it is recommended to enable the input hysteresis block on both blocks via
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