Figure 86: Stdi Horizontal Locking Operation; Figure 87: Stdi Hsync Monitoring Operation - Analog Devices Advantiv ADV7604 Hardware Manual

line 3-line4≦threshold? line 3-line4≦threshold?
line 1-line2≦threshold? line 1-line2≦threshold?
line 3 line 3
line 1 line 1 line 2 line 2
line 2-line3≦threshold? line 2-line3≦threshold?
line 4-line5≦threshold? line 4-line5≦threshold?
Once the STDI locks to the incoming video, it registers the first BL measurement (first eight lines)
as latched data (absolute line length: L) and keeps monitoring and comparing each successive line
length with the absolute line length (L/8).
The STDI horizontally unlocks if 128 consecutive lines have a line length greater than the threshold.
line 1 line 1 line 2 line 2 line 3 line 3
First 8 blocks of line length = BL read back value First 8 blocks of line length = BL read back value
Registered as "Absolute Line Length" Registered as "Absolute Line Length"
Rev. F August 2010
line 5-line6≦threshold? line 5-line6≦threshold?
line 4 line 4 line 5 line 5 line 6 line 6 line 7 line 7
Monitors 128 consecutive lines before STDI horizontally "Lock" Monitors 128 consecutive lines before STDI horizontally "Lock"

Figure 86: STDI Horizontal Locking Operation

line 4 line 4 line 5 line 5 line 6 line 6 line 7 line 7
L L

Figure 87: STDI HSync Monitoring Operation

line 8 line 8
line 129 – L/8 ≦threshold? line 129 – L/8 ≦threshold?
line 8 line 8
"L/8" will be registered as absolute line length reference for each "L/8" will be registered as absolute line length reference for each
lines after STDI horizontally locks to the incoming video signal lines after STDI horizontally locks to the incoming video signal
271
line 128 line 128 line 129 line 129
line 131 – L/8 ≦threshold? line 131 – L/8 ≦threshold?
line 130 line 131 line 130 line 131
line 128 line 129 line 128 line 129
line 130 – L/8 ≦threshold? line 130 – L/8 ≦threshold?
ADV7604