I have an application that requires 24 bit color. I would like to use the INTB pin as a control output on the 925 to reflect the input on the 926 INTB_IN. The datasheet shows this is a normal function, however attempts to write register C6 via the 926 deserializer using the BCC appear to not set any bits in the register. All registers above 0xA0 appear return 0x00 when read including the HDCP TX ID (FX) register set. Are these registers restricted to local access only? I can read and write the configuration registers in the 0x0X range and communicate with the External Video interface via I2C so this isn't a basic question of the BCC functioning.
Please note that parts I am testing with are from a design released in 2015.