TMC22191 CADEKA [Cadeka Microcircuits LLC.], TMC22191 Datasheet - Page 44

• Manufacturer Part Number: TMC22191
• Description: Digital Video Encoders/Layering Engine
• Manufacturer: CADEKA [Cadeka Microcircuits LLC.]

TMC22091/TMC22191
Genlock Interface
The TMC22x91 can process digital composite video
connected to its CVBS port. It has been designed to couple
tightly with the companion TMC22071 Genlocking Video
Digitizer, but it will work with other sources as well.
The digital composite video has to be in standard 8-bit
binary format at a PXCK/2 rate. Synchronization with the
internal PXCK/2 is established by the phasing of the
GHSYNC input, as shown in Figures 24 and 25.
44
GHSYNC
CVBS 7-0
COMPOSITE
PXCK
OUTPUT
PXCK
CVBS
PD
0
V N+2
P N
1
2
t SGI
V N+3
P N+1
3
FIRST KEY WORD
4
2N+1
V N+4
P N+2
5
6
Figure 24. Genlock Interface Timing
t HGI
V N+5
P N+3
7
Figure 23. Data Keying
8
V N+6
P N+4
9
Subcarrier frequency and phase data are transmitted to the
encoder over the CVBS bus as 4-bit nibbles on CVBS
during the horizontal sync period. Field identification is also
required for the TMC22x91 internal sync generator. The
14th nibble of the sequence contains no relevant data.
t SGI
V N+25
P N+23
38
39
V N+26
P N+24
40
2N+2
41
V N+27
P N+25
t HGI
42
43
V N+28
P N+26
KEY MIDPOINT
44
PRODUCT SPECIFICATION
45
V N+29
P N+27
46
47
V N+30
P N+28
48
24360A
2N+3
49
3-0
24341A