GS1559 Data Sheet
4.10.5.5 Line Based CRC Error Detection
The GS1559 will calculate line based CRC words for HD video signals for both the
Y and C data channels. These calculated CRC values are compared with the
received CRC values and any mismatch is flagged in the YCRC_ERR and/or
CCRC_ERR bits of the ERROR_STATUS register.
Line based CRC error flags will only be generated when the device is operating in
HD mode, (SD/HD = LOW).
If a CRC error is detected in the Y channel, the YCRC_ERR bit in the error status
register will be set HIGH. If a CRC error is detected in the C channel, the
CCRC_ERR bit in the error status register is set HIGH. Y and C CRC errors will
also be generated if CRC values are not received.
4.10.5.6 HD Line Number Error Detection
When operating in HD mode, the GS1559 will calculate line numbers based on the
timing generated by the internal flywheel. These calculated line numbers are
compared with the received line numbers for the Y channel data and any mismatch
is flagged in the LNUM_ERR bit of the ERROR_STATUS.
Line number errors will also be generated if line number values are not received.
4.10.5.7 TRS Error Detection
TRS errors flags are generated by the GS1559 when:
1. The received TRS timing does not correspond to the internal flywheel timing;
or
2. The received TRS hamming codes are incorrect.
Both 8-bit and 10-bit SAV and EAV TRS words are checked for timing and data
integrity errors. These are flagged via the SAV_ERR and/or EAV_ERR bits of the
ERROR_STATUS register.
Timing-based TRS errors will only be generated if the FW_EN/DIS pin is set HIGH.
NOTE: In HD mode, (SD/HD = LOW), only the Y channel TRS codes will be
checked for errors.
30572 - 4 July 2005
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GENNUM [ GENNUM CORPORATION ]
