Samsung S5PC100, Руководство пользователя

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TVOUT & VIDEO DAC S5PC100 USER’S MANUAL (REV1.0)
9.7-14
This waveform is inserted at the 23rd line of 625/50 standard video. The register SDO_ARMWSS625 is used for
carrying the 14-bit data into the waveform. Bits {b3, b2, b1, b0} specify display aspect ratio control, bits {b7, b6,
b5, b4} are used for enhanced TV service, bits {b10, b9, b8} is used for European teletext subtitle control, and bits
{b13, b12, b11} are used for copy control.
3.5
WAVEFORM GENERATION AND CHROMA MODULATION (CVBS MODULE)
The CVBS sub-module combines the timing information and video data to make the waveforms of ITU-R BT 470
TV signals. This procedure is done by two different data paths. One is for luminance data (Y) and the other is for
chrominance data (C). For the luminance data path, horizontal/ vertical synchronization pulses are formed and
merged to a properly scaled and offset luminance video data (Y). For the chrominance data paths, base band
chrominance data (Cb and Cr) are modulated with a sub-carrier FSC along with the video standard, i.e.
C(n) = U(n) * sin(2
π
FSC * n) + V(n) * cos(2
π
FSC * n),
where U(n) and V(n) denote properly scaled and offset versions of Cb(n) and Cr(n), respectively. Then a pilot
sinusoidal waveform, called a burst, is formed and added prior to the start of modulated chrominance data C at
each line. At the end of CVBS sub-module data paths, the luminance data (Y) and the chrominance data (C) is
merged into one channel and form composite data (CVBS).
The CVBS sub-module also provides the color space conversion for YPbPr/RGB component outputs. The
following figure summarizes the data path in the CVBS sub-module.
HV S Y NC/V B I DA TA
Y/G
PB/B
P R/R
Y
CVBS
C
B urs t
Y
CB
CR
DA C 0
DA C 1
DA C 2
Color
S pac e
Convers ion
QAM
Figure 9.7-12 Data Flow of CVBS Sub-Module
The SEL_COMPONENT and SEL_CHAN0_OUTPUT… SEL_CHAN5_OUTPUT bits in SDO_CONFIG register is
used for output selection.