GS2971 Datasheet, PDF (62/148 Pages) Semtech Corporation – 3Gb/s, HD, SD SDI Receiver, with Integrated Adaptive Cable Equalizer complete with SMPTE Audio and Video Processing

4.14 Data Format Detection & Indication
In addition to detecting the video standard, the GS2971 detects the data format, i.e. SDTI,
SDI, TDM data (SMPTE 346M), etc.
This information is represented by bits in the DATA_FORMAT_DSX register accessible
through the host interface.
Data format detection is only carried out when the LOCKED signal is HIGH.
By default (at power up or after system reset), the DATA_FORMAT_DSX register is set to
Fh (undefined). This register is also set as undefined when the LOCKED signal is LOW
and/or the SMPTE_BYPASS pin is LOW.
Table 4-12: Data Format Register Codes
YDATA_FORMAT[3:0] or
CDATA_FORMAT[3:0]
0h ~ 05h
Data Format
SDTI
6h
7h
8h
9h
Ah ~ Eh
Fh
SDI
Reserved
TDM
HD-SDTI
Reserved
Non-SMPTE data
format
Remarks
SMPTE 321M, SMPTE 322M,
SMPTE 326M
−
−
SMPTE 346M
−
−
Detected data format is not SMPTE.
SMPTE_BYPASS = LOW or LOCKED =
LOW
The data format is determined using the following criteria:
• If TRS ID words are detected but no SDTI header or TDM header is detected, then
the data format is SDI
• If TRS ID words are detected and the SDTI header is available then the format is
SDTI
• If TRS ID words are detected and the TDM data header is detected then the format is
TDM video
• No TRS words are detected, but the PLL is locked, then the data format is unknown
NOTE: Two data format sets are provided for HD video rates. This is because the Y and
Cr/Cb channels can be used separately to carry SDTI data streams of different data
formats. In SD video mode only the Y data format register contains the data, and the C
register is set to Fh (undefined format).
GS2971 3Gb/s, HD, SD SDI Receiver
Data Sheet
45898 - 2
September 2012
62 of 148