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Overall System Control

Overall System Control
There are three microprocessors in the control panel and either seven or
eight microprocessors in the switcher frame. In the switcher frame there are
two Control Processor Modules (Control Processor 1 and Control
Processor 2).
The multiple microprocessors are designed to prevent total loss of system
control if one of the processors fails. To accomplish this some of the
modules have address and data buses for more than one processor. If one
of the processors fails, the rest of the system continues to function but with
some reduced capability.
The control signals begin in the control panel. The push-buttons and shaft
encoders of the control panel are scanned and any change in the status of
the controls is noted by the appropriate controller and sent to the Control
Processor Modules in the switcher frame.
The Control Processor Modules interpret these signals and send each of the
modules in the switcher frame the correct signal to do the requested
operation. Information programmed in the system (i.e. which input is
assigned to which push-button) is stored on the Control Processor Modules
and is called upon to interpret the information from the control panel.
M/E 1 control is handled by the M/E Mezzanine Module (068916) installed
on Control Processor 1 (064805).
M/E 2 control is accomplished by the M/E Mezzanine Module (068916)
installed on Control Processor 2 (064806).
DSK control is handled by the Head of State (HOS) Mezzanine Module
(068919) installed on Control Processor 1 (064805).
The HOS processor has overall control of the system.
Strobe: There is a strobe from the processor modules to each of the other
modules to select that module.
Batteries: Each of the processor modules has a lithium battery installed.
They are the power source for the battery backed up RAM when power is
removed from the module.
CAUTION
Be careful not to short out the battery. This can cause permanent damage to the
battery and loss of the data in battery backed up RAM.

Control Processor 1 Module (064805) (Slot A1)

The Control Processor 1 Module has three processors, one on the processor
module and one on each of two mezzanine modules.