AEQ DIGITAL COMMENTARY UNIT Customer's Manual page 81

This window allows network scanning to determine the number of Commentary
Control Units (CCU) and Commentary Units (CU) that are connected and
operative (see fig. 4.4.2.1.B).
When the Test button is pressed the computer will begin to scan the network
searching for CCUs. Each CCU has its own unique node address. When a
CCU is detected, the computer will obtain information regarding the number of
CMs and CUs that are controlled by this CCU. The total amount of CCUs, CMs
and CUs found in the network are displayed in the Total CCU, Total CM and
Total CU fields. Additionally, the computer displays the highest CCU address
found in the network.
The control computer uses polling methods to scan and detect network
components. It starts from the lowest address (0) and then it explores every
consecutive address, and stores the addresses, as used or unused, in a
memory map.
This information is then used for network polling in two different ways:
• For valid addresses: the computer continuously polls valid addresses using
short time periods.
• For unused addresses: the computer performs statistical polling in a less
restrictive time schedule.
This approach ensures a faster response to existing CCU requirements, while
newly introduced network components will require more time to be recognized.
Setting the maximum node address number prevents the control computer from
scanning the network above this address, thus giving a faster response to
changing situations.
Digital Commentary System
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