Transitioning Of Power Modes; Structure Of Internal E-Edid For Port A - Analog Devices Advantiv ADV7619 Hardware User's Manual

Hardware User Guide

TRANSITIONING OF POWER MODES

If the part starts in Power-Down Mode 0 and then transitions into a different power mode (that is, Power-Down Mode 1 or normal
operation mode), the information in the internal E-EDID is not overwritten. The internal E-EDID remains active on the HDMI port for
which the E-EDID has been accessed. This prevents disturbing E-EDID read requests from HDMI sources connected to the ADV7619
while it is being powered on, or while the power mode is transitioning.
It is possible to disable the automatic enable of internal EDID on the HDMI ports when the part comes out of power-down mode, by
setting the DISABLE_AUTO_EDID bit.
DISABLE_AUTO_EDID, Addr 64 (Repeater), Address 0x7A[1]
Disables all automatic enables for internal E-EDID.
Function
DISABLE_AUTO_EDID Description
0 (default) Automatic enable of internal E-EDID on HDMI port when the part comes out of Power-Down Mode 0
1 Disable automatic enable of internal E-EDID on HDMI port when the part comes out of Power-Down Mode 0

STRUCTURE OF INTERNAL E-EDID FOR PORT A

The internal E-EDID is enabled on Port A by setting EDID_A_ENABLE to 1. The structure of the internal E-EDID that is accessible on
the DDC line of Port A is shown in Figure 5. The image of the internal E-EDID that is accessed on the DDC bus of Port A corresponds to
the data image contained in the internal E-EDID RAM.
Notes
•
After EDID_A_ENABLE is set to 1, the ADV7619 E-EDID/Repeater controller calculates the four checksums of the E-EDID image
for Port A and updates the internal RAM address locations 0x7F, 0xFF, 0x17F, and 0x1FF in the internal E-EDID RAM with the
computed checksums.
•
After power up, the ADV7619 E-EDID/Repeater controller sets all bytes in the internal E-EDID RAM to 0, this operation takes less
than 1 ms. It is recommended to wait for at least 1 ms before initializing the EDID map with an E-EDID image.
•
When internal E-EDID is enabled on Port A, the hot plug should not be asserted until the EDID map has been completely initialized
with E-EDID.
•
The internal E-EDID can be accessed in read-only mode through the DDC interface at the I
•
The internal E-EDID can be accessed in read/write mode through the general I
PORT A E-EDID STRUCTURE
0x1FF BLOCK 2 CHECKSUM
BLOCK 3
0x180
0x17F BLOCK 2 CHECKSUM
BLOCK 2
0x100
0xFF
BLOCK 1 CHECKSUM
BLOCK 1
0x80
0x7F BLOCK 0 CHECKSUM
BLOCK 0
0x00
Figure 5. Port A E-EDID Structure and Mapping
Rev. A | Page 35 of 204
0x1FE
0x17E
0xFE
0x7E
2
C address 0xA0.
2
C interface at the EDID map I
UG-237
2
C address.