AK8813 Datasheet, PDF (24/51 Pages) Asahi Kasei Microsystems – NTSC/PAL Digital Video Encoder

ASAHIKASEI
[AK8813/14]
♦ WSS
AK8813/14 supports WSS(ITU-R.Bt.1119) encoding for the distinction of an aspect ratio etc. Setting or
Resetting the WSS-bit of [ Video Process 2 Register(02H) ], this function is switched On/Off. The data is
set by using [ WSS Data Register(08H, 09H) ].
WSS Data Renewal Timing
VSYNC
I²C SDA
Set C ontrol R egister
NEW DATA
DATA
OLD DATA
NEW DATA
Fig. 8 WSS Data Renewal Timing
500mV +/- 50%
0H
1.5usec
10.5usec
11.0 +/- 0.25usec
27.4usec
38.4usec
44.5usec
Encode Line: Line 23
Coding: bi-phase modulation coding
Clock: 5MHz (Ts = 200ns)
Run-in
Start code
29 elements
24 elements
0x1F1C71C7
0x1E3C1F
Fig. 9 WSS Wave Form
Group 1
Aspect ratio
24 elements
Bit numbering
0123
LSB MSB
0 : 000111
1 : 111000
Group 2
Enhanced
Services
24 elements
Bit numbering
4567
LSB MSB
0 : 000111
1 : 111000
Group 3
Subtitles
18 elements
Bit numbering
8 9 10
LSB MSB
0 : 000111
1 : 111000
Group4
Reserved
18 elements
Bit numbering
11 12 13
LSB MSB
0 : 000111
1 : 111000
Rev.00
- 25 -
2004/Oct