Table 17. Optional Enhanced Link Integrity Check—Performed Every 16 Frames After
Encryption is Enabled
NO.
µC
HDCP GMSL SERIALIZER
HDCP GMSL DESERIALIZER
1
—
Generates Pj and updates the
PJ register every 16 VSYNC
cycles.
Generates Pj’ and updates the PJ’
register every 16 VSYNC cycles.
2
—
Continues to encrypt and
transmit A/V data.
Continues to receive, decrypt, and
output A/V data.
3
Every 16 video frames, reads PJ from the
GMSL serializer and PJ’ from the deserializer.
—
—
4
If PJ matches PJ’, the enhanced link integrity
check is successful; go back to step 3.
—
—
5
If there is a mismatch, retry up to two more
times from step 3. Enhanced link integrity
check fails after 3 mismatches. After the
detection of failure of enhanced 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.
—
—
6
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.
7
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 │
52
