Digital Alert Systems DASDEC II User Manual page 109

Alert Type Priority Selection Use this interface to configure the associated priority number for EAS alert codes.
The scheme is based upon five EAS groups: Advisories, Tests, Watches, Warnings, and Emergencies. The
exact alerts that fall into each category is defined on the DASDEC II at Server > Help > EAS Codes.
Discussion: DVS644/SCTE 18 provides for 16 priority values. However, reserved uses for most values mean
that in practice, priority values are 0, 3, 7, 11 and 15, with 15 being the highest priority alerts. The priority of 0
has a special meaning. An alert sent with 0 priority will establish a new set-top box or TV sequence number. The
sequence number is incremented (modulo 32) whenever an alert is sent with updated information. The DASDEC
II supports this reset mode by allowing an alert to be set to 0 priority. This setting should only be used for one
alert, and then changed to 1-15. There is also a field to extend the alert duration past the default DASDEC II
audio duration. Keep in mind that the maximum allowed time for a DVS644/SCTE 18 message is 120 seconds.
Immediate Start (Alert Start Time)
This checkbox toggle sets the EAS Alert message start time on receiving device. When enabled, the start time of
the alert on the receiving device is immediate upon reception. When disabled (unchecked), the Alert Start Time
is set to use a clock based start time. The actual time used is the EAS alert UTC. If a clock time is used, it is
CRITICAL that the DASDEC II and the receiving device be time synchronized.
Alert Text Control
This pull-down menu list programs when the alert text section of the DVS-644/SCTE18 message is sent, based
on alert priority. This feature allows text to not be sent if the priority becomes higher than a specified value. This
allows the STB to omit alert text crawls when a force tune to a details channel is made based upon alert priority.
Alert Repeat Control and Alert Message Repeat Period
The DASDEC II can be configured to periodically resend the alert message, with the DVS-644/SCTE 18 Cable
Alert message field alert_time_remaining field decremented automatically. This is controlled using the Alert
Repeat Control selections. The options are based on alert priority, allowing repetition to be invoked for alerts
above a given priority. When repetition is selected, the Alert Message Repeat Period field for entering the time
period (in seconds from 6 to 60) is also displayed.
Alert Message Transmission Duplication Count (1-20)
When a forwarded/originated alert is sent to a DVS-644 client at a specific IP address, the DVS-644/SCTE-18
MPEG-2 System table is generated and sent to the MPEG multiplexor client. Programming this interface controls
the number of times the table is sent as a duplicate, from 1 - 20 times, to insure downstream reception.
Additional Start Delay Time (seconds)
This toggle allows time to be added before the DVS-644/SCTE-18 Cable Alert Message is first sent over the
network. The formula for the delay time is: Start Delay == (Audio Delay if enabled) + Additional Time.
Duration Extension Time (seconds). - This field allows some extra time to be added to the alert duration
programmed into the Cable Alert Message alert_time_remaining field. The maximum time allowed for this field
is 120 seconds. This can be used to guarantee a minimum amount of time for short Weekly Test alerts. The
formula for the Alert Duration is: Alert Duration == Audio Duration + Extension Time (max total is 120 seconds).
All FIPS codes trigger
If enabled, all alert FIPS codes will trigger the DVS644/SCTE18 client interface. In the next screen shot this
option is disabled. Set the checkbox to enable/disable FIPS code filtered trigger control. If disabled, then the alert
FIPS codes are filtered for at least one specific match as a way to control whether or not DVS644/SCTE18 is
triggered. Alerts for specific FIPS areas can be filtered as a way to control whether or not DVS644/SCTE18 is
triggered. If All FIPS is disabled, select FIPS codes from the provided lists and add to the client FIPS list. If any
of these FIPS are included in the incoming active forwarded/originated alert, the alert will be sent using the DVS-
644/SCTE18 client. With careful use of this feature, and with multiple clients, one DASDEC II can serve many
different cable regions at the same time.
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Digital Alert Systems: DASDEC User Manual