GS1560A Gennum Corporation, GS1560A Datasheet - Page 38

• Manufacturer Part Number: GS1560A
• Description: Reclocking Deserializer For HD-SDI, Sd-sdi & Dvb-asi With Loop Thru Cable Driver. 3.3/1.8V Supply.
• Manufacturer: Gennum Corporation

3.10.3 SMPTE 352M Payload Identifier
The GS1560A can receive and detect the presence of the
SMPTE 352M payload identifier ancillary data packet. This
four word payload identifier packet may be used to indicate
the transport mechanism, frame rate and line scanning /
sampling structure.
Upon reception of this packet, the device will extract the
four words describing the video format being transported
and make this information available to the host interface via
the four VIDEO_FORMAT_OUT registers (Table 6).
Table 6: Host Interface Description for SMPTE 352M Payload Identifier Registers
3.10.4 Automatic Video Standard and Data Format Detection
The GS1560A can independently detect the input video
standard and data format by using the timing parameters
extracted from the received TRS ID words. This information
is
VIDEO_STANDARD register (Table 7).
Total samples per line, active samples per line, total lines
per field/frame and active lines per field/frame are also
calculated and presented to the host interface via the
RASTER_STRUCTURE registers (Table 8). These line and
sample count registers are updated once per frame at the
end of line 12. This is in addition to the information
contained in the VIDEO_STANDARD register.
After
RASTER_STRUCTURE registers default to zero.
GENNUM CORPORATION
VIDEO_FORMAT_OUT_B
VIDEO_FORMAT_OUT_A
REGISTER NAME
presented
Address: 013h
Address: 012h
device
reset
to
the
or
BIT
15-
7-0
15-
7-0
8
8
host
power
SMPTE352M
SMPTE352M
SMPTE352M
SMPTE352M
interface
NAME
Byte 4
Byte 3
Byte 2
Byte 1
up,
the
via
Data will be available in this register when Video
Payload Indentification Packets are detected in the
data stream.
Data will be available in this register when Video
Payload Indentification Packets are detected in the
data stream.
Data will be available in this register when Video
Payload Indentification Packets are detected in the
data stream.
Data will be available in this register when Video
Payload Indentification Packets are detected in the
data stream.
four
the
38 of 55
The VIDEO_FORMAT_OUT registers will only be updated if
the received checksum is the same as the locally
calculated checksum.
These registers will be cleared to zero, indicating an
undefined format, if the device loses lock to the input data
stream (LOCKED = LOW), or if the SMPTE_BYPASS pin is
asserted LOW. This is also the default setting after device
reset or power-up.
The SMPTE 352M packet should be received once per field
for interlaced systems and once per frame for progressive
systems. If the packet is not received for two complete
video frames, the VIDEO_FORMAT_OUT registers will be
cleared to zero.
DESCRIPTION
R/W
R
R
R
R
DEFAULT
27360-1
0
0
0
0