E-Edid/Repeater Controller - Analog Devices ADV7850 Hardware Manual

Function
hpa_ovr_term
0 
1

7.4 E-EDID/REPEATER CONTROLLER

The HDMI section incorporates an E-EDID/Repeater controller, which performs the following tasks:
•
Computes the E-EDID checksums for the four ports
• Updates the SPA value after the E-EDID image is loaded from the SPI EEPROM into the internal E-EDID RAM
•
Performs the repeater routines described in Section
The E-EDID/Repeater controller is powered from the DVDD supply and clocked by an internal ring oscillator. The controller and the
internal DDC bus arbiter are kept active in cable supply mode (refer to Section 7.5.1), which allows the internal Enhanced-Extended
Display Identification (E-EDID) to be functional and accessible through the DDC port even when the part is powered down. In the cable
supply mode, all the power needed by the ADV7850 can be provided by one or more HDMI transmitters connected to the HDMI ports.
These HDMI transmitters can then read the capabilities of the powered down application integrating the ADV7850 by accessing its
internal E-EDID through the DDC ports.
The E-EDID/Repeater controller is reset when the DVDD supplies go low or when
EDID/Repeater controller reboots, it performs the following tasks:
• Clears the internal E-EDID and KSV RAM (refer to Section
• Computes a total of seven checksums for all four ports (refer to Section 7.10)
• Updates the SPA registers (refer to Section 7.11)
hdcp_rept_edid_reset, Addr 68 (HDMI), Address 0x5A[3] (Self-Clearing)
This control is used to reset the E-EDID/repeater controller. When asserted, it resets the E-EDID/repeater controller. This is a self
clearing bit.
Function
hdcp_rept_edid_reset
0 
1
disable_hdcp_ddc_a, Addr 64 (Repeater), Address 0x7B[0]
This control is used to disable the DDC port in the HDCP address.
Function
disable_hdcp_ddc_a
0 
1
disable_hdcp_ddc_b, Addr 64 (Repeater), Address 0x7B[1]
This control is used to disable the DDC port in the HDCP address.
Function
disable_hdcp_ddc_b
0 
1
Rev. A May 2012
Description
Automatic or manual I2C control of port termination
Termination controls disabled and overridden by HPA controls
7.38
Description
Normal operation
Reset E-EDID/repeater controller
Description
HDCP address in DDC port is active if port is active or BG
Disable DDC HDCP address, requests to it will not be acknowledged nor serviced
Description
HDCP address in DDC port is active if port is active or BG
Disable DDC HDCP address, requests to it will not be acknowledged nor serviced
hdcp_rept_edid_reset
7.5 and Section 7.23.2)
141
ADV7850
is set to 1. When the E-