Harris Atlas DVL400, Техническое руководство

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2/25/03 888-2473-001 4-7
WARNING: Disconnect primary power prior to servicing.
Section 4 Theory of Operation
ATLAS Series™
4.3.4 System Control Bus
The System Control Bus is a multi-conductor ribbon cable which distributes the
CAN (Controller Area Network) bus and several parallel control lines to all micro-
controllers in the system. System Control Bus connection points include:
1. Main Controller
2.
Backplane Interface Board
3.
PA Module Controllers (via the Backplane Interface Board)
4.
RF Monitor Board
5. PS (Power Supply) Monitor Board
6. External I/O Board
7. Second PA Cabinet (for DVL 4300 and DVL 5700 only)
4.3.4.1 CAN Bus
The CAN bus is the primary communication and control system in the transmitter. It
is a high speed serial communications network in which information is merely
broadcast over the network. All of the system control boards are monitoring the
information on the network, but will only respond to information relevant to each
controllers operation. All control boards also have the ability to send information
over the CAN bus. All fault reporting and status and metering information displayed
on the GUI is sent on the CAN bus to the Main Controller and to the External I/O
board for remote monitoring. Transmitter control signals are also sent via CAN but
are also sent over hardwired parallel control lines.
4.3.4.2 Parallel Control Lines
The parallel control lines are used for quick actuation of critical functions, such as
ON, OFF, RF mute, PS mute, AC_Low and Fault Off. These lines are also the
backup control lines in Life Support mode when the Main Controller (and therefore
the CAN bus) is not operational. Each board in the control system can
independently activate some or all of the parallel control lines to protect the
transmitter in case of a fault or other condition that may adversely affect the
transmitter. These parallel control signals are duplicated in the CAN messages. The
following is a brief explanation of each of the parallel control lines included in the
system control bus.