User's Manual

Table Of Contents
4-6 888-2687-001 10/19/07
WARNING: Disconnect primary power prior to servicing.
Ranger ™ Mobile Series
Section 4 Theory of Operation
4.3.5 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
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.
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.
a. ON_/OFF
This command corresponds to the transmitter operator pushing the
“ON” or “OFF” button, thereby turning the transmitter on or off
respectively. This signal is high for ON and low for OFF. This is
driven only by the Main Controller and is a sense only line for the
rest of the control boards.