Alarm Descriptions
72
VTM-2400 Installation and Operation Handbook
CRC HD
The CRC HD alarm occurs when the internally calculated CRC value is different from the
received CRC value (High definition only).
Table 5-1. CRC Alarm Error Types
Error Type
Description
CRC ERRORED
SECONDS
The integer number of seconds in which an EDH or CRC error has existed.
SAV PLACED
INCORRECTLY
SAV is relative to EAV. The number of words is a constant for any given video
format between EAV and SAV. EAV is detected and used as the reference.
The correct number of words is counted, and then SAV is detected. The SAV
Placed Incorrectly alarm occurs when a proper SAV sequence is not detected
or if SAV is detected before the correct number of words between EAV and
SAV.
LINE LENGTH
ERROR
The Line Length Error occurs when there are an incorrect number of words
between EAV and SAV.
FIELD LENGTH
ERROR
The number of lines is constant between the B bit going high and the start of
vertical blanking. The Field Length Error occurs when there is deviation in the
line number count.
RESERVED VALUES
USED IMPROPERLY
The Reserved Values Used Improperly alarm occurs when the eight most
significant bits (SD) or all ten bits (HD) are all “1” or “0” in any place other than
an EAV, SAV, or ancillary header.
ANCILLARY DATA
CHECKSUM ERROR
The Ancillary Data Checksum Error occurs when the internal calculated CRC
value is different from the received CRC value.
ANCILLARY DATA
PARITY ERROR
The Ancillary Data Parity Error occurs when the internal calculated parity
value does not match the received data.
ANCILLARY DATA
PLACEMENT ERROR
The Ancillary Data Placement Error occurs if an ancillary header appears
outside of blanking.
ABSENCE OF SERIAL
VIDEO INPUT
The Absence of Serial Video Input error occurs when no timing reference
signal is detected.
Loss of Carrier
The Loss of Carrier alarm occurs when there is no TRS (Timing Reference Signal) detected.
Digital Gamut
RGB Upper/Lower
The RGB Upper and Lower alarm occurs when any component of the transcoded RGB signal
falls outside the upper or lower limits for a period in excess of the duration setting. The
Sensitivity can be increased to provide immunity to fast transcoding spikes.
