Vertical Filters And Measurements - Analog Devices Advantiv ADV7604 Hardware Manual

7.15.4 Vertical Filters and Measurements

The ADV7604 integrates a vertical filter that performs measurements on the VSync of the HDMI
stream. These measurements are available in the HDMI Map and can be used to determine the
resolution of the incoming video data.
7.15.4.1 Vertical Filter Locking Mechanism
The HDMI vertical filter locks if the input VSync comes at exactly the same line count for two
consecutive lines. The HDMI vertical filter also unlocks if the VSync comes at a different pixels
count for two consecutives lines.
7.15.4.2 Vertical Filter Measurements
The HDMI vertical filter performs the measurement described in this section.
The field 0 measurements are adequate to determine the standard of incoming progressive modes. A
combination of field 0 and field 1 measurements should be used to determine the standard of
interlaced modes.
Notes:
• The vertical measurements are valid only if
• The HDMI vertical filter is used solely to measure the vertical synchronization signals
decoded from the HDMI stream. This filter is not in the main path of the synchronization
processed by the part and does not delay the overall HDMI data in to video data out latency.
V_LOCKED_RAW, Vertical Filter Locked Flag, IO Map, Address 0x6A, [7]
Function
V_ LOCKED_RAW
0
1
Field 0 measurements are used to determine the video modes that are progressive.
FIELD0_TOTAL_HEIGHT[12:0], Total Number of Lines in Field 0, HDMI Map, Address 0x26,
[4:0]; Address 0x27, [7:0]
Function
FIELD0_TOTAL_HEIGHT
[12:0]
xxxxx xxxxxxx
Rev. F August 2010
V_LOCKED_RAW
Description
Vertical filter has not locked
Vertical filter has locked and vertical synchronization parameters
are valid for readback
Description
Total number of half lines in field 0
128
ADV7604
is set to 1.