ASAHI KASEI
[AK8817/18]
(17) Video ID
The AK8817/18 supports to encode the Video ID ( EIAJ CPR-1204 ) which distinguishes the aspect ratio etc..
This is also used as CGMS ( Copy Generation Management System ).
Turning “ON/OFF” of this function is made by setting both VMOD-bit = 0 and VBID-bit = 1 of { Control 1 Register (0x00) }.
And data to be set is written into { VBID / WSS Data1 & 2 Registers ( 0x02,0x03 )}.
Video ID information is the highest order of priority information among VBI information
VBID Data Update timing
VSYNC
.
Set Control Register
NEW DATA
u-P Data
DATA
OLD DATA
NEW DATA
VBID Code assignment
20 bit data is configured with WORD0 = 2 bit, WORD1 = 4 bit, WORD2 = 8 bit and CRC = 6 bit.
CRC is automatically calculated and added by the AK8817/18.
Default values of CRC polynomial expression X6 + X + 1 are all ones.
-data configuration
bit1
bit20
DATA
WORD0
2bit
WORD1
4bit
WORD2
8bit
CRC
6bit
VBID Waveform
bit1 bit2 bit3
bit20
Ref.
•••
70IRE +/- 10IRE
+ 10 IRE
0IRE
− 5 IRE
2.235usec +/- 50nsec
11.2usec +/- 0.3usec
49.1usec +/- 0.44usec
1H
525/60 System
Amplitude
Encode Line
70IRE
20/283
Rev.001E
33
2009 / 12
AKM [ ASAHI KASEI MICROSYSTEMS ]
