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Signal Status
Indicates one of the following 3 states, OK, LOSS, or ERRORS.
The latter is shown when the signal is bad or disconnected
and the received ASI characters are invalid. OK and LOSS are
used to indicate a TS sync condition.
ASI Carrier Frequency
Typically 270MHz, is measured to an accuracy of 1ppm and
a resolution of 10 Hz
TS Datarate
Is the number of data characters per seconds. All special
'K' characters are discarded as these are used as stuffing.
This measurement is independent whether or not a valid TS
is being transmitted. The error in part per million (ppm)
from the expected datarate is also calculated.
Byte Mode / Burst Mode Packet Counts
Are sorted into byte mode or burst mode and measured as packets
per second. A faulty ASI TS may consist of either combination
of these modes due to multiplexers trying to insert packets
in a TS in the wrong format. Byte mode is when each ASI data
character is seperated by 2 or more special 'K' stuffing characters.
Burst mode is when all 188, 204 or 208 data bytes are sent
continuously with 2 or more special 'K' stuffing characters
after the last data character and before the next sync byte
data character.
Sync Byte Jitter
Consists of a 4 byte header, the first of which is a 0x47
synchronisation byte. This is often used for Phase Lock Loops
(PLLs) in clock recovery circuits. Ideally these sync bytes
should be regular, but even one missing packet will make the
sync byte arrive twice as late.
Data Byte Jitter
Contains data bytes which may be sequential in burst mode
or stuffed with special 'K' characters as in byte mode. This
measurement wil show the minimum and maximum number of special
'K' characters found between data bytes.
Null Packet Bitrate
In a TS are identified by a PID or 0x1FFF. These are used
to stuff a TS when there is insufficient video, audio or other
data to be transmitted to fill the required data rate.
Character Violations
Are any received ASI characters either special or data bytes
that are not valid 10 bit ASI codes will cause an increase
in the character violation counter. This can indicate whether
an ASI feed has errors due to bad signal levels and not by
a multiplexer or encoder.
Windows GUI
Software application allows monitoring and logging capability.
Alarms
Are provided by a comprehensive multi level alarm signalling
for critical alarm status.
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