Dolby Laboratories DP569 - Manual (Page 26)

Model DP569 User’s Manual Applications
3-4
3.1.5 Alarms and Monitoring
The DP569 has a bypass input that can be used for redundant or hot standby
operation. In order to connect a pair of DP569 for hot standby, the following
connections should be made.
Main Program
Output
Main Program
Audio
Optional Terminator
Not Connected
Bypass In
Bypass In
Switched
Out
Not Used
Main
Out
Main
Out
Digital
In
Digital
In
DP569 Standby Encoder
DP569 Primary Encoder
Switched
Out
Normal
Bypass
Dolby Digital
Encode Processing
Dolby Digital
Encode Processing
Figure 3-3 Hot-Standby Operation of the DP569
The unit automatically enters Bypass mode when an internal fault occurs or when
power to one unit is lost. Bypass mode can also be selected from the I/O Control
menu or via the GPI/O input port.
For further security, pins 1 and 9 (ground) of the GPI/O ports can be used to control a
unit fault alert. If pin 1 goes “low,” then a power supply or hardware fault has
occurred. These can be used on both the encoders so that a faulty standby encoder can
be identified before it is required. Pins 3, 4, and 9 can also be used to ascertain
whether the unit is producing an encoded output, and to trigger a warning.
3.1.6 Quick Start for Digital Television Broadcasting
This section describes the steps necessary to configure the DP569 for typical operation.
1. After unpacking the unit, connect the Digital Audio Inputs to the DP569 using
termination as required. See Section 2.2.2, Digital Audio Inputs.