GRASS VALLEY IQH4B, Руководство пользователя

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Control Panels
An enclosure and the modules that it contains may be controlled by the following methods:
• Control panels connected via the RollCall communications network.
• Computers connected via the RollCall communications network.
• SNMP managers connected via IP.
• Any combination of the above.
RollCall Communications System
RollCall remote control gives a uniquely powerful and flexible system that can be as simple as a
single rack unit with control panel, or a powerful multi-master, multi-slave configuration with
PC control and monitoring for full station automation.
The RollCall command protocol obtains control information from the IQ module being
addressed. This unique feature ensures that module updates or additions will not require
control system software upgrades - simply plug in and switch on.
When the unit (or module) is powered-up the module will normally assume the same set-up
conditions that existed at the last power-down. This information is provided by non-volatile
memory on the module. Some modules incorporate methods that allow other set-up
conditions to exist on power-up; please consult the information specific to each module for
details.
RollCall Network System Details
The IQ Modular system has a flexible and powerful remote control system. The units in the
system are joined via a high-speed network. Each box enclosure is a node on the network. A
single local area network can have a maximum of 255 nodes with any combination of control
panels and modular rack boxes. With the 3U box holding up to 16 cards, the system can
accommodate 4080 (255 x 16) cards. Each box is physically addressed via switches on the
Remote Control Interface.
Network bridges can be used to connect each network to up to 15 others, nested up to 4 levels,
allowing tens of thousands of networks and millions of units to be joined together.
IQH4B enclosures have two interface connections to the RollCall network:
• RollNet 75 Ohm coaxial BNC running at 2.5 Mbps. The IQH4B enclosure represents a 2-unit
load .
• RJ45 Ethernet running at 10/100 Mbps.
RollNet 75 Ohm Coaxial Interface
This interface allows connections of units to a single section of 75 Ohm video cable. Each unit is
physically joined via a T or Y-piece connector. Each end of the section is terminated by a 75
Ohm resistor at each end of the cable. The data rate on this interface is 2.5 Mbps. Each section
of cable can be up to 400 m.
Example configuration
:
3U Box
3U Box
1U Box
75 Ohm Network
Front Panel
75 Ohm
Terminator
75 Ohm
Terminator