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ADV7611 BKSV when to be ready from host CPU?

Question asked by T.F. Employee on Sep 27, 2012
Latest reply on Oct 17, 2012 by T.F.

Hi,

 

Please advise on when host CPU can read valid BKSV values from the REPEATER.BKSV registers after powering up?

 

It seems ADV7611 itself loads the BKSV content from its OTP 1.8ms after powering up as said in UG-180, but at this stage it's not readable in the REPEATER.BKSV registers from the host CPU. The HDMI.HDCP_KEYS_READ is not available as well.

 

I found that I have to bring the part out of power=down mode by resetting IO.POWER_DOWN bit in order for REPEATER_BKSV registers to be filled and HDCP_KEYS_READ is available, and once the BKSV registers are filled it keeps the value and still readable when I bring the part to power-down mode again by setting the POWER_DOWN bit.

 

After that, I brought the part to reset by either hardware reset, or software reset by IO.MAIN_RESET bit, and either way I found that BKSV register contents are cleared as well as HDMI.HDCP_KEYS_READ and had to let the part come out of power-down mode again in order to read the BKSVs and the HDMI.HDCP_KEYS_READ.

 

So would you let me know if following interpretation is correct? Thanks.

 

1. The 'loading' of the BKSVs from OTP to ADV7611 internal BKSV registers (which is not host I/F I2C registers) takes place only once on hardware poring up of the part, and it takes 1.8ms. Once loaded the internal BKSV registers are kept regardless hardware/software reset or entering power-down mode.

 

2. REPEATER.BKSV registers and HDMI.HDCP_KEYS_READ register are cleared on hardware-power down, hardware/software reset. The contents of these registers are internally transffered from internal BKSV registers to REPEATER.BKSV registers on resetting IO.POWER_DOWN bit.

 

3. When hardware/software reset is applied the REPEATER.BKSV registers are cleared. However, internal BKSV content are still kept so once the part comes out of power-down mode by resetting IO.POWER_DOWN, REPEATER.BKSV are immidiately filled again from the internal BKSV registers.

 

 

Thanks in advance, TF

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