Table 16. Link Integrity Check (Normal)—Performed Every 128 Frames After
Encryption is Enabled
NO.
µC
HDCP GMSL SERIALIZER
HDCP GMSL DESERIALIZER
1
—
Generates Ri and updates the
RI register every 128 VSYNC
cycles.
Generates Ri’ and updates the RI’
register every 128 VSYNC cycles.
2
—
Continues to encrypt and
transmit A/V data.
Continues to receive, decrypt, and
output A/V data.
3
Every 128 video frames (VSYNC cycles) or
every 2s.
—
—
4
Reads RI from the GMSL serializer.
—
—
5
Reads RI’ from the deserializer.
—
—
6
Reads RI again from the GMSL serializer and
makes sure it is stable (matches the previous
RI that it has read from the GMSL serializer). If
RI is not stable, go back to step 5.
—
—
7
If RI matches RI’, the link integrity check is
successful; go back to step 3.
—
—
8
If RI does not match RI’, the link integrity
check fails. After the detection of failure of
link integrity check, the µC makes sure that
A/V data not requiring protection (low-value
content) is available at the GMSL serializer
inputs (such as blue or informative screen).
Alternatively, the FORCE_VIDEO and
FORCE_AUDIO bits of the GMSL serializer
can be used to mask A/V data input of the
GMSL serializer.
—
—
9
Writes 0 to the ENCRYPTION_ENABLE bit of
the GMSL serializer and deserializer.
Disables encryption and
transmits low-value content A/V
data.
Disables decryption and outputs low-
value content A/V data.
10
Restarts authentication by writing 1 to the
RESET_HDCP bit followed by writing 1 to the
START_AUTHENTICATION bit in the GMSL
serializer.
—
—
MAX9277/MAX9281
3.12Gbps GMSL Serializers for Coax or
STP Output Drive and LVDS Input
www.maximintegrated.com
Maxim Integrated │
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