adv7174 Analog Devices, Inc., adv7174 Datasheet - Page 43

• Manufacturer Part Number: adv7174
• Description: Chip Scale Pal/ntsc Video Encoder With Advanced Power Management
• Manufacturer: Analog Devices, Inc.

APPENDIX 4—WIDE SCREEN SIGNALING (WSS)
The ADV7174/ADV7179 supports WSS, conforming to the
standard. WSS data is transmitted on Line 23. WSS data can
only be transmitted when the ADV7174/ ADV7179 is
configured in PAL mode. The WSS data is 14 bits long, the
function of each of these bits is as shown below. The WSS data
is preceded by a run-in sequence and a start code (see Figure 58).
The bits are output from the configuration registers in the
FUNCTION OF WSS BITS
Table 22. Bit 0–Bit 2 Bit 3 is the odd parity check of Bit 0–Bit 2
B0
0
1
0
1
0
1
0
1
500mV
B1
0
0
1
1
0
0
1
1
B2
0
0
0
0
1
1
1
1
11.0Ps
B3
1
0
0
1
0
1
1
0
Aspect
Ratio
4:3
14:9
14:9
16:9
16:9
>16:9
14:9
16:9
SEQUENCE
RUN-IN
Format
Full
Format
Letterbox
Letterbox
Letterbox
Letterbox
Letterbox
Full
Format
Not
Applicable
START
CODE
Position
Not
Applicable
Center
Top
Center
Top
Center
Center
Not
Applicable
42.5Ps
38.4Ps
W0 W1 W2 W3 W4 W5 W6 W7 W8 W9 W10 W11 W12 W13
Figure 58. WSS Waveform Diagram
Rev. A | Page 43 of 52
following order: C/W20 = W0, C/W21 = W1, C/W22 = W2,
C/W23 = W3, C/W24 = W4, C/W25 = W5, C/W26 = W6,
C/W27 = W7, C/W10 = W8, C/W11 = W9, C/W12 = W10,
C/W13 = W11, C/W14 = W12, C/W15 = W13. If the Bit C/W07
is set to a Logic 1, it enables the WSS data to be transmitted on
Line 23. The latter portion of Line 23 (42.5 µs from the falling
edge of HSYNC ) is available for the insertion of video.
Table 23. Bit 4–Bit 7
Bit
B4
B5
B6
B7
B8
B9–B10
B11
B12
B13
Value
0
1
0
1
0
1
0
1
0, 0
1, 0
0, 1
1, 1
0
1
Description
Camera Mode
Film Mode
Standard Coding
Motion Adaptive Color Plus
No Helper
Modulated Helper
Reserved
No Teletext Subtitles
Teletext Subtitles
No Open Subtitles
Subtitles in Active Image Area
Subtitles out of Active Image Area
Reserved
No Surround Sound Information
Surround Sound Mode
Reserved
Reserved
ADV7174/ADV7179
ACTIVE
VIDEO