GS2972 Datasheet, PDF (81/125 Pages) Semtech Corporation – 3G/HD/SD-SDI Serializer with Complete SMPTE Audio & Video Support

4.10 SMPTE ST 352 Data Extraction
If there are no SMPTE ST 352 packets embedded in the input signal, the GS2972 will raise
an error flag in the “NO_352_ERR” bit.
If there are ST 352 packets present in the stream, the GS2972 reports the extracted
SMPTE ST 352 packets in the VIDEO_FORMAT_352_IN registers in the host interface.
The user can use this information, along with the RASTER_STRUC_X registers, to
determine the video format.
If there is a conflict between the numbers in the RASTER_STRUC_X registers and the
format defined in the SMPTE ST 352 packets, the GS2972 will raise a TIMING_ERR flag
via the host interface.
Note: SMPTE ST 352 packets will not be present in an HD-SDTI input stream, and will
not be embedded in an output HD-SDTI serial stream. This is controlled by the user as
described in Section 4.9.8.1.
By default (at power up or after system reset), the VIDEO_FORMAT_352_IN registers are
set to zero (undefined video format). These registers are also cleared when the
SMPTE_BYPASS pin is set LOW, or the LOCKED pin is LOW. The SMPTE ST 352 packet
should be received once per field for interlaced systems and once per frame for
progressive video systems. If the packet is not received for two complete video frames,
the VIDEO_FORMAT_352_IN registers are cleared to zero.
Table 4-24: SMPTE ST 352 Packet Data
Register Name
Bit
Bit Name
Description
VIDEO_FORMAT_352_IN_WORD_2
VIDEO_FORMAT_352_IN_WORD_1
VIDEO_FORMAT_352_IN_WORD_4
VIDEO_FORMAT_352_IN_WORD_3
15-8
7-0
15-8
7-0
15-8
7-0
15-8
7-0
VIDEO_FORMAT_IN_
DS1_4
(Byte 4)
VIDEO_FORMAT_IN_
DS1_3
(Byte 3)
VIDEO_FORMAT_IN_
DS1_2
(Byte 2)
VIDEO_FORMAT_IN_
DS1_1
(Byte 1)
VIDEO_FORMAT_IN_
DS2_4
(Byte 4)
VIDEO_FORMAT_IN_
DS2_3
(Byte 3)
VIDEO_FORMAT_IN_
DS2_2
(Byte 2)
VIDEO_FORMAT_IN_
DS2_1
(Byte 1)
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
Data will be available in this register
when Video Payload Identification
Packets are detected in the data stream.
R/W Default
R
0
R
0
R
0
R
0
R
0
R
0
R
0
R
0
GS2972 3G/HD/SD-SDI Serializer with Complete
SMPTE Audio & Video Support
Final Data Sheet Rev. 9
GENDOC-047479 September 2013
www.semtech.com
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