Figure 3-8.—Example of a maintenance console.
console is operational, its controls override those of the
operator panel but not the remote operator console. The
registers on the maintenance console are represented by
pushbutton indicators. During operations, the registers
provide status. Signals generated by the maintenance
console, CPU, and IOC are displayed by the pushbutton
indicators.
The indicators can indicate that the
computer is talking to other subsystems, such as the
display or link subsystems. Monitoring the registers
and controls is also performed during periods of
preventive maintenance or when a computer
malfunction occurs.
During maintenance you can set parameters or you
can manually control the computer using different
modes and varying speeds. Another useful function is
inspect and change, where you can manually interface
with the CPU and IOC for software enhancement. The
maintenance console has the following four levels of
controls and indications:
l Console indications
l Initiate computer operations
l Monitor computer operations
l Testing (automatic and manual)
KEYBOARDS
Keyboards are your primary means of controlling
the operations of microcomputers. They are also used
in minicomputers and mainframe computers. They will
probably be your main means for inputting programs
and data into microcomputers/PCs. A monitor (color
or monochrome) is used with the keyboard to view and
monitor the operations.
A monitor is a microcom-
puter’s principal means of providing information to
you. The monitor allows the microcomputer to
communicate its actions to you, so that you can act upon
those actions using the keyboard to accomplish
whatever job you are doing. From a keyboard,
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