參數(shù)資料
型號: ADV7324KSTZ
廠商: ANALOG DEVICES INC
元件分類: 顏色信號轉(zhuǎn)換
英文描述: Multiformat 216 MHz Video Encoder with Six NSV 14-Bit DACs
中文描述: COLOR SIGNAL ENCODER, PQFP64
封裝: LEAD FREE, MS-026BCD, LQFP-64
文件頁數(shù): 70/92頁
文件大?。?/td> 992K
代理商: ADV7324KSTZ
ADV7324
APPENDIX 3—SD CLOSED CAPTIONING
[Subaddresses 0x51 to 0x54]
Rev. 0 | Page 70 of 92
The ADV7324 supports closed captioning conforming to the
standard television synchronizing waveform for color
transmission. Closed captioning is transmitted during the
blanked active line time of Line 21 of the odd fields and
Line 284 of the even fields.
Closed captioning consists of a 7-cycle sinusoidal burst that is
frequency- and phase-locked to the caption data. After the
clock run-in signal, the blanking level is held for two data bits
and is followed by a Logic 1 start bit. Sixteen bits of data follow
the start bit. These consist of two 8-bit bytes, seven data bits,
and one odd parity bit. The data for these bytes is stored in the
SD closed captioning registers [Address 0x53 to Address 0x54].
The ADV7324 also supports the extended closed captioning
operation, which is active during even fields and encoded on
Line 284. The data for this operation is stored in the SD closed
captioning registers [Address 0x51 to Address 0x52].
All clock run-in signals and timing to support closed captioning
on Line 21 and Line 284 are generated automatically by the
ADV7324. All pixels inputs are ignored during Line 21 and
Line 284 if closed captioning is enabled.
FCC Code of Federal Regulations (CFR) 47, section 15.119, and
EIA608 describe the closed captioning information for Line 21
and Line 284.
The ADV7324 uses a single-buffering method. This means that
the closed captioning buffer is only 1 byte deep; therefore, there
will be no frame delay in outputting the closed captioning data,
unlike other 2-byte-deep buffering systems. The data must be
loaded one line before it is output on Line 21 and Line 284. A
typical implementation of this method is to use VSYNC to inter-
rupt a microprocessor, which in turn will load the new data
(2 bytes) in every field. If no new data is required for transmission,
0s must be inserted in both data registers; this is called nulling.
It is also important to load control codes, all of which are double
bytes, on Line 21, or a TV will not recognize them. If there is a
message such as “Hello World” that has an odd number of char-
acters, it is important to add a blank character at the end so that
the end-of-caption, 2-byte control code lands in the same field.
D0–D6
D0–D6
10.5
±
0.25
μ
s
12.91
μ
s
7 CYCLES OF
0.5035MHz
CLOCK RUN-IN
REFERENCE COLOR BURST
(9 CYCLES)
FREQUENCY = F
= 3.579545MHz
AMPLITUDE = 40 IRE
10.003
μ
s
50 IRE
40 IRE
27.382
μ
s
33.764
μ
s
BYTE 1
BYTE 0
TWO 7-BIT + PARITY
ASCII CHARACTERS
(DATA)
S
T
A
R
T
P
A
R
I
T
Y
P
A
R
I
T
Y
0
Figure 97. Closed Captioning Waveform (NTSC)
相關(guān)PDF資料
PDF描述
ADV7340 Multiformat Video Encoder, Six 12-Bit Noise Shaped Video㈢ DACS
ADV7340BSTZ Multiformat Video Encoder, Six 12-Bit Noise Shaped Video㈢ DACS
ADV7340EBZ Multiformat Video Encoder, Six 12-Bit Noise Shaped Video㈢ DACS
ADV7341 Multiformat Video Encoder, Six 12-Bit Noise Shaped Video㈢ DACS
ADV7341BSTZ Multiformat Video Encoder, Six 12-Bit Noise Shaped Video㈢ DACS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ADV7330 制造商:AD 制造商全稱:Analog Devices 功能描述:Multiformat 11-Bit Triple DAC Video Encoder
ADV73305502 制造商:LG Corporation 功能描述:FRAME ASSEMBLY
ADV73306701 制造商:LG Corporation 功能描述:Frame Assembly
ADV73306702 制造商:LG Corporation 功能描述:Frame Assembly
ADV73306703 制造商:LG Corporation 功能描述:Frame Assembly