bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 46

• Manufacturer Part Number: bt829bkrf
• Description: Video Streamii Decoders
• Manufacturer: ETC-unknow

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1.0 Functional Description
1.9 Bt829B VBI Data Output Interface
1.9.3 Functional Description
1.9.4 VBI Line Output Mode
There are three modes of operation for the Bt829B VBI data pass-through feature:
The VBI line output mode is enabled via the VBIEN bit in the VTC Register
(0x1B). When enabled, the VBI data is output during the VBI active period. The
VBI horizontal active period is defined as the interval between consecutive
Bt829B HRESET signals. Specifically, it starts at a point one CLKx1 interval
after the trailing edge of the first HRESET and ends with the leading edge of the
following HRESET. This interval is coincident with the HACTIVE signal as
indicated in Figure 1-19.
Figure 1-19. VBI Line Output Mode Timing
uously at CLKx1 or CLKx2 rate during VBI. Valid VBI data is available one
CLKx1 (or QCLK) interval after the trailing edge of HRESET. When the Bt829B
is configured in VBI line output mode, it is generating invalid data outside of the
VBI horizontal active period. In standard YCrCb output mode, the horizontal
active period starts at a time point delayed from the leading edge of HRESET as
defined by the value programmed in the HDELAY register.
1
2
3
DVALID is always at a logical 1 during VBI. Also, QCLK is operating contin-
HACTIVE
HRESET
VD[15:0]
VBI Data Pass through Disabled. This is the default mode of operation for
the Bt829B during which the device decodes composite video and gener-
ates a YCrCb 4:2:2 data stream.
VBI Line Output Mode. The device outputs unfiltered 8*Fsc data only dur-
ing the vertical interval which is defined by the VACTIVE output signal
provided by the Bt829B. Data is output between the trailing edge of the
VRESET signal and the leading edge of VACTIVE. When VACTIVE is
high, the Bt829B is outputting standard YCrCb 4:2:2 data. This mode of
operation is intended to be used to enable capture of VBI lines containing
ancillary data in addition to processing normal YCrCb 4:2:2 video image
data.
VBI Frame Output Mode. In this mode the Bt829B treats every line in the
video signal as if it were a vertical interval line and outputs only the unfil-
tered 8*Fsc data on every line (i.e., it does not output any image data). This
mode of operation is designed for use in still-frame capture/processing
applications.
D829BDSA
VBI Data
VideoStream II Decoders
Bt829B/827B