E-Edid Support For Power-Down Mode 0 - Analog Devices Advantiv ADV7604 Hardware Manual

EDID_B_ENABLE_CPU, Internal E-EDID for Port B Flag, Repeater Map, Address 0x7D, [1]
Function
EDID_B_ENABLE_CPU
0
1
EDID_C_ENABLE_CPU, Internal E-EDID for Port C Flag, Repeater Map, Address 0x7D, [2]
Function
EDID_C_ENABLE_CPU
0
1
EDID_D_ENABLE_CPU, Internal E-EDID for Port D Flag, Repeater Map, Address 0x7D, [3]
Function
EDID_D_ENABLE_CPU
0
1
Notes:
When the internal E-EDID is enabled on more than one port (e.g. ports A and B), the
•
corresponding enable controls (e.g.
set high in one single I
If the internal E-EDID RAM is enabled for one specific port (e.g. port A), an external E-
•
EDID storage device should not be connected on the DDC bus of that port.
The internal EDID can be read accessed by Current Address Read sequences on the DDC
•
ports (refer to Section 16.2.1).
The ADV7604 supports the segment pointer, which is set at device address 0x60 through the
•
DDC bus, and used in combination with the internal EDID address (0xA0) to access the
internal E-EDID.
7.3.1

E-EDID Support for Power-down Mode 0

The ADV7604 supports E-EDID access in power-down mode. Using this feature, a device that
integrates the ADV7604 in standby can make its E-EDID available to the HDMI transmitter. This
allows support of CEC and compatibility with HDMI transmitters that require the E-EDID to be
available when the HDMI receiver is powered down.
The power-down mode E-EDID is only made available when power-down mode 0 is entered via the
PWRDNB pin (see Section 3.2.1) – this enables the part in a very low power state with only the
minimum of internal circuitry enabled for the internal E-EDID. This allows the EDID/Repeater
controller to load the EDID image from an external SPI PROM into the internal EDID RAM. Once
the full E-EDID image is read from the SPI PROM into the ADV7604, the E-EDID will be made
available.
The EDID/Repeater controller also updates the SPA of each port (refer to Section 7.4.3.1), computes
the required E-EDID checksums, and enables the internal E-EDID as follows:
Rev. F August 2010
Description
Internal E-EDID for port B disabled
Internal E-EDID for port B enabled
Description
Internal E-EDID for port C disabled
Internal E-EDID for port C enabled
Description
Internal E-EDID for port D disabled
Internal E-EDID for port D enabled
EDID_A_ENABLE
2
C write. This ensures the fastest calculation of the checksums.
94
and EDID_B_ENABLE) should be
ADV7604