Bosch Appliances Home Security System 3.5 User Manual

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Bosch Security Systems | 2011-02
2011-02 | Installation and User Instructions | 2 | Introduction
en | 78
3
Calls
3.1 Introduction
As Praesideo is a public address and emergency sound 
system, it is used to distribute background music, live 
speech and evacuation messages. All audio in the 
system is distributed in the form of calls. 
3.2 Call 
attributes
3.2.1
Introduction
A call always consists of the following attributes:
Priority (see section 3.2.2)
Call content (see section 3.2.3)
Routing (see section 3.2.4)
Timing (see section 3.2.5)
3.2.2
Priority
To each call, a priority is assigned. When two or more 
calls are addressed to the same zone or need shared 
resources (e.g. the message player), the system only 
starts the call with the highest priority. The range of 
priorities that is available for a call depends on the type 
of call (see table 3.1).
Calls with the same priority operate on first come first 
serve basis, except in the case of priority 255: calls with 
the same priority 255 overrule each other, so the latest 
becomes active. This assures that high priority 
microphones that are left behind in an active state will 
never block the system.
3.2.3 Call content
The content of a BGM call typically consists of an audio 
signal coming from a BGM source, such as a CD player 
or a tuner. The content of normal calls and emergency 
calls is defined by a call macro, which can consist of:
A start chime
Prerecorded message(s)
Live  speech
An end chime
3.2.4
Routing
The routing of the call is the set of zones to which the 
call is intended to be addressed. Whether the call 
actually is addressed to the selected zones depends on 
the priority of the call (see section 3.2.2) and its routing 
scheme.
Each call can have one of the following routing 
schemes:
Partial
Non-partial
Stacked
By definition, partial calls do not require the entire 
routing to be available at the start of the call and during 
the call. When a partial call is started and a part of the 
routing is not available, the call is only distributed to the 
available part of the routing. When a part of the routing 
becomes unavailable during the call, the call continues 
in the parts of the routing that are still available.
Non-partial calls are calls that require the entire routing 
to be available at the start of the call and during the call. 
When during the call a part of the routing becomes 
unavailable, the call is aborted. 
Stacked calls are calls that have been recorded for later 
playback. This feature is only available in combination 
with a call stacker (see chapter 23). 
table 3.1: Priorities and call types
Priority
Call type
0 to 31
BGM calls
32 to 223
Normal calls
224 to 255
Emergency calls
Note
Non-partial normal calls can only be started 
when the entire routing is available. BGM and 
emergency calls can be started when the entire 
routing is not available.
Note
BGM calls and emergency calls without live 
speech are started in the non available parts of 
the routing as soon as these parts are released.