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GS1531 Data Sheet
30573 - 4
July 2005
37 of 49
4.6.3.4 Ancillary Data Checksum Generation and Insertion
The GS1531 will calculate checksums for all detected ancillary data packets
presented to the device. These calculated checksum values are inserted into the
data stream prior to serialization.
Ancillary data checksum generation and insertion will only take place if the
ANC_CSUM_INS bit of the IOPROC_DISABLE register is set LOW.
4.6.3.5 Line Based CRC Generation and Insertion
The GS1531 will generate and insert line based CRC words into both the Y and C
channels of the data stream. This feature is only available in HD mode and is
enabled by setting the CRC_INS bit of the IOPROC_DISABLE register LOW.
4.6.3.6 HD Line Number Generation and Insertion
In HD mode, the GS1531 will calculate and insert line numbers into the Y and C
channels of the output data stream.
Line number generation is in accordance with the relevant HD video standard as
determined by the device, see
Automatic Video Standard Detection on page 28
.
This feature is enabled when SD/HD = LOW, and the LNUM_INS bit of the
IOPROC_DISABLE register is set LOW.
4.6.3.7 TRS Generation and Insertion
The GS1531 can generate and insert 10-bit TRS code words into the data stream
as required. This feature is enabled by setting the TRS_INS bit of the
IOPROC_DISABLE register LOW.
TRS word generation will be performed in accordance with the timing parameters
generated by the flywheel which will be locked either to the received TRS ID words
or the supplied H, V, and F timing signals, see
Internal Flywheel on page 25
.
4.7 Parallel-To-Serial Conversion
The parallel data output of the internal data processing blocks is fed to the
parallel-to-serial converter. The function of this block is to generate a serial data
stream from the 10-bit or 20-bit parallel data words and pass the stream to the
integrated cable driver.