Error Logic; Input Error Logic; Decoder Error Logic; Temperature Error Logic - Cisco D9887B Installation And Configuration Manual

Error Logic

Input Error Logic

The input status is based on the selected input card's status and the transport error
indicator bit in the transport stream being decoded. For example, if the current input
is VSB, the input status is based on: VSB receiver lock, RF channel level, and the
MER level. The RF channel and MER thresholds can be set by the user. If the unit
detects the presence of the transport error bit in a transport packet header, the input
status will be an error for 0.5 seconds each time the TS error bit is set. The system
must detect a constant cadence of sync bytes (0x47h) every 188 bytes and detect a
valid PAT at least every 500 ms in order for the INPUT LED to illuminate.

Decoder Error Logic

The decoder error indicator is based on the decoder's ability to decode what the user
has requested. The input status will be alarmed differently depending on the current
decoding mode:
In "Auto Mode," the decoder status will be good unless the Video or Audio

decoders cannot decode a stream. For example: a stream defines program 4 to
have video on PID 52. If PID 52 is not actually present in the stream, or is un-
decodable, the decoder status will be in the error state. This is true for all modes.
In "PID Lock Mode," the decoder status will be good if all of the PIDs entered by

the user, for video and audio, are being decoded by the unit. If the user wants
nothing to be decoded, the PID should be set to 0. If the user enters a PID which
is not present or cannot be decoded, the decoder status will be in the error state.
In "Program Priority Mode," the decoder status will be good if any priority is

currently active and the Audio and Video represented by that priority are being
decoded. If the PMT for a selected program lists a video or audio PID, but the
decoder cannot decode that PID, the indicator will be in the error state. If the
user enters an index for a priority that does not exist in the PMT, the indicator
will still be good because the decoder will be set to decode nothing on that audio
output.

Temperature Error Logic

The temperature error indicator is based on the correct operation of the unit. If the
unit's internal temperature exceeds 70 °C, the temperature status will be in the error
state.
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Error Logic

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