GS2971A Datasheet, PDF (74/152 Pages) Gennum Corporation – Integrated audio clock generator

6. Ancillary data checksum error correction and insertion.
7. Audio extraction.
8. SMPTE 372M (Level B to Level A) Conversion.
All of the above features are only available in SMPTE mode (SMPTE_BYPASS = HIGH).
To enable these features, the IOPROC_EN/DIS pin must be set HIGH, and the individual
feature must be enabled via bits in the IOPROC_DISABLE register.
The IOPROC_DISABLE register contains one bit for each processing feature allowing
each one to be enabled/disabled individually.
By default (at power up or after system reset), all of the IOPROC_DISABLE register bits
are LOW, enabling all of the processing features.
To disable an individual processing feature, set the corresponding IOPROC_DISABLE bit
HIGH in the IOPROC_DISABLE register.
Table 4-15:IOPROC_DISABLE Register Bits
Processing Feature
TRS error correction and insertion
Y and C line based CRC error correction
Y and C line number error correction
Ancillary data check sum correction
EDH CRC error correction
Illegal code re-mapping
H timing signal configuration
Update EDH Flags
Audio Data Extraction
Ancillary Data Extraction
Audio Extraction
Regeneration of 352M packets
IOPROC_DISABLE Register Bit
TRS_INS
CRC_INS
LNUM_INS
ANC_CHECKSUM_INSERTION
EDH_CRC_INS
ILLEGAL_WORD_REMAP
H_CONFIG
EDH_FLAG_UPDATE_MASK
AUDIO_SEL
ANC_DATA_EXT
AUD_EXT
REGEN_352M
4.18.1 TRS Correction & Insertion
When TRS Error Correction and Insertion is enabled, the GS2971A generates and
overwrites TRS code words as required.
TRS Word Generation and Insertion is performed using the timing generated by the
Timing Signal Generator, providing an element of noise immunity over using just the
received TRS information.
This feature is enabled when the IOPROC_EN/DIS pin is HIGH and the
TRS_INS_DISABLE bit in the IOPROC_DISABLE register is set LOW.
NOTE: Inserted TRS code words are always 10-bit compliant, irrespective of the bit
depth of the incoming video stream.
GS2971A 3Gb/s, HD, SD SDI Receiver
Data Sheet
54311 - 2
September 2012
74 of 152