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ADV7344
Rev. 0 | Page 50 of 88
LCC1
SFL
P19 TO P10
ADV7403
VIDEO
DECODER
CLKIN_A
SFL/MISO
Y9 TO Y0/
S9 TO S0
5
RTC
LOW
128
TIME SLOT 01
13
0
14
21
19
F
SC
PLL INCREMENT
2
VALID
SAMPLE
INVALID
SAMPLE
6768
0
RESET BIT
4
RESERVED
ADV7344
8/LINE
LOCKED
CLOCK
5 BITS
RESERVED
1
FOR EXAMPLE, VCR OR CABLE.
2
F
SC
PLL INCREMENT IS 22 BITS LONG. VALUE LOADED INTO ADV7344 F
DDS REGISTER IS
F
PLL INCREMENTS BITS 21:0 PLUS BITS 0:9 OF SUBCARRIER FREQUENCY REGISTERS.
3
SEQUENCE BIT
PAL: 0 = LINE NORMAL, 1 = LINE INVERTED
NTSC: 0 = NO CHANGE
4
RESET ADV7344 DDS.
5
SELECTED BY SUBADDRESS 0x01, BIT 7.
Figure 62. SD Subcarrier Frequency Lock Timing and Connections Diagram (Subaddress 0x84, Bits[2:1] = 11)
COMPOSITE
VIDEO
1
H/L TRANSITION
COUNT START
14 BITS
SUBCARRIER
PHASE
SEQUENCE
BIT
3
DAC 1
DAC 2
DAC 3
DAC 4
DAC 5
DAC 6
4 BITS
RESERVED
0
SD VCR FF/RW SYNC
Subaddress 0x82, Bit 5
In DVD record applications where the encoder is used with a
decoder, the VCR FF/RW sync control bit can be used for
nonstandard input video, that is, in fast forward or rewind modes.
In fast forward mode, the sync information at the start of a new
field in the incoming video usually occurs before the correct
number of lines/fields is reached. In rewind mode, this sync
signal usually occurs after the total number of lines/fields is
reached. Conventionally, this means that the output video has
corrupted field signals because one signal is generated by the
incoming video and another is generated when the internal
line/field counters reach the end of a field.
When the VCR FF/RW sync control is enabled (Subaddress 0x82,
Bit 5), the line/field counters are updated according to the
incoming VSYNC signal and when the analog output matches
the incoming VSYNC signal.
This control is available in all slave-timing modes except Slave
Mode 0.
VERTICAL BLANKING INTERVAL
Subaddress 0x31, Bit 4; Subaddress 0x83, Bit 4
The ADV7344 is able to accept input data that contains VBI
data (such as CGMS, WSS, VITS) in SD, ED, and HD modes.
If VBI is disabled (Subaddress 0x31, Bit 4 for ED/HD;
Subaddress 0x83, Bit 4 for SD), VBI data is not present at the
output and the entire VBI is blanked. These control bits are
valid in all master and slave timing modes.
For the SMPTE 293M (525p) standard, VBI data can be
inserted on Line 13 to Line 42 of each frame, or on Line 6 to
Line 43 for the ITU-R BT.1358 (625p) standard.
VBI data can be present on Line 10 to Line 20 for NTSC and on
Line 7 to Line 22 for PAL.
In SD Timing Mode 0 (slave option), if VBI is enabled, the
blanking bit in the EAV/SAV code is overwritten. It is possible
to use VBI in this timing mode as well.
If CGMS is enabled and VBI is disabled, the CGMS data is
nevertheless available at the output.
SD SUBCARRIER FREQUENCY REGISTERS
Subaddress 0x8C to Subaddress 0x8F
Four 8-bit registers are used to set up the subcarrier frequency.
The value of these registers is calculated using:
Register
Frequency
Subcarrier
32
2
MHz
27
×
=
in
line
video
one
in
cycles
clk
of
Number
line
video
one
periods
subcarrier
of
Number
where the sum is rounded to the nearest integer. For example, in
NTSC mode:
569408543
2
1716
5
227
32
=
×
=
Value
Register
Subcarrier
where:
Subcarrier Register Value
= 569408543d = 0×21F07C1F
SD F
SC
Register 0: 0x1F
SD F
SC
Register 1: 0x7C
SD F
SC
Register 2: 0xF0
SD F
SC
Register 3: 0x21
Programming the F
SC
The subcarrier frequency register value is divided into four F
SC
registers as shown in the previous example. The four subcarrier
frequency registers must be updated sequentially, starting with
Subcarrier Frequency Register 0 and ending with Subcarrier
Frequency Register 3. The subcarrier frequency updates only
after the last subcarrier frequency register byte has been
received by the ADV7344.