Table of Contents
Advertisement
File Grouping & Hierarchy:
The audio files on this unit are organised into four distinct groups; the first three can
each contain up to five files, but the fourth group (background music) has no practical
file limit. These groups have been given descriptive names so as to help organise
and ease access to the data.
The files and their groups have a hierarchical priority structure as shown in the table
below:
Group
Name
No of Files
Group 1
Messages
5
Group 2
Tones
5
Group 3
Chimes
5
Group 4
BGM
256
Group1 has priority over all the other groups and will automatically override their
output. It also has its own internal file hierarchy whereby one message may override
a lower message in the group, i.e. message 1 has the highest priority and message
5 has the lowest.
Groups 2 and 3 have priority over Group 4.
There is no set limit to the size (duration) of any file, it is dependant purely on the
USB memory stick capacity. For example, using 128Kb/s, a 500Mb stick could
store approximately 8 hours whereas a 1Gb stick could store approximately 16
hours. Obviously, if a higher bit rate is used (higher quality) the time will be reduced
accordingly.
Group 4 is intended for background music (BGM) and could contain the contents
of several music CDs. All files (tracks) are played continuously and in a random
order. Activation of this BGM facility is by means of a contact closure or shorting link,
removing the contact closure or link disables the facility. Activation of any file in any
of the other groups will automatically override the output from this group.
The playing of any file can be stopped by applying a contact closure to the remote
stop contacts on the internal board.
12
Priority Level
Internal Hierarchy
1
Yes
2
No
2
No
3
No
File Activation Output:
Whenever a file from the first three groups is playing, a 'File Active' output (open
collector NPN transistor) is switched on. This can be used to control or activate other
equipment directly or indirectly by using an external relay.
The relay can be powered by the unit directly if it is a low current 12v type (i.e. it
consumes less than 100mA); however, if a different voltage type is required, up to
maximum of 30v, then it must be powered externally by a separate power supply,
again it must not consume more than 100mA. A clamping diode, a 1N4004 or similar
type, should always be fitted across the terminals of the relay coil.
Diagrams showing the two types of wiring configurations are shown below:
13
Advertisement
Table of Contents
