UG-707
ADV8005 Hardware Reference Manual
2.2.7.
SPI Loop Through
SPI ports can be put in loop through mode for programming the external SPI flash that may be connected to the
master SPI port (if an OSD design is to be used). Refer to Section
for more information.
spi_loop_through
, IO Map,
Address 0x1AB6[5]
This bit is used to enable SPI loop through mode. In loop through mode, Serial Port 1 (SCK1, MOSI1, MISO1 and CS1) is connected to the
Serial Port 2 (SCK2, MOSI2, MISO2, CS2).
Function
spi_loop_through
Description
0 (default)
Regular SPI mode
1
SPI slave clock routed to SPI master clock output
2.2.8.
VBI Data Insertion
supports VBI data (such as CGMS, WSS, and CCAP) insertion into the video stream through either the ancillary data input (Y channel
input of 36-bit data bus) or the SPI-compatible slave input (VBI_SCK, VBI_MOSI and VBI_CS). When using the SPI-compatible slave input for
VBI insertion, a reduced set of video input formats are supported on the EXOSD TTL input due to the shared pins. The VBI data is decoded
and supplied to the encoder for output in the video data stream.
The supported VBI standards are the following:
•
WSS (625i)
•
CCAP (525i and 625i)
•
CGMS (525i)
•
CGMS (525p)
•
CGMS (625p)
2.2.8.1.
Extraction Overview
VBI data can be supplied to the
through two separate interfaces. If there is a pixel bus input from the front end decoder then the VBI
data may be provided via an ancillary data stream encoded into the video data. If a pixel bus is not available, the VBI data can be sent via the
dedicated SPI interface. Refer to
for an overview of this architecture.
Figure 40: VBI Data Extraction Block Diagram
2.2.8.2.
Ancillary Data Extraction
The ancillary data which is encoded in either nibble mode or byte mode is extracted from the input data stream on the Y channel and the VBI
data is retrieved. The DID and SDID from the sending device must match the value programmed in 1A 1A4A[7:0] and 1A 1A4B[7:0]. The
Ancillary
Data
Extractor
External
SPI
Master
1
0
sclk
SPI
Slave
Sync
1
0
Ancillary
Data
Delay
To Encoder
ss
mosi
spi_rx_dv
1’b1
y_data_in[11:4]
vbi_src (1 = SPI, 0 = ANC)
muxed_vid_in
spi_rx_dv[7:0]
ccap_even_data
ccap_even_dv
ccap_odd_data
ccap_odd_dv
cgms_wss_data
cgms_wss_dv
ccap_out
ccap_ext_out
cgms_wss_out_sd
cgms_wss_out_hd
c
lk
_
o
u
t_
s
d
c
lk
_
o
u
t_
h
d
1
0
hdmi_rx_clk
vid_rx_clk
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