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PATTERN SUMMARY
Once HDCP has been enabled, the screen will appear similar to the following:
The HDCP pattern provides a full three phase authentication:
Phase 1:
a The HD Pattern Signal Generator writes a 64-bit random number (AN) to the sink
/ receiver (Rx).
b The receiver responds by sending its own KSV (BKSV) to the transmitter (Tx).
The Receiver also sends the repeater bit, used to determine if the sink / receiver
acts as a repeater. During this step, the transmitter also verifi es that BKSV has
not been revoked and has the proper format
c If AKSV and BKSV are deemed to be valid, then the receiver (sink) and transmitter
(source) each generate R0 (the receiver generates R0*. R0* is read by the
transmitter and compared with R0. If R0 = R0* then the authentication phase is
successful. If they are not equal, HDCP authentication will fail.
Phase 2:
d As long as R0 = R0’, the transmitter will begin sending encrypted video.
Phase 3:
e Every 128 frames (2 sec), the Tx and Rx generate a value RI which is similar to
the R0 values. Comparing these values between the Tx and Rx verifi es that the
link is synchronized.