DIGITAL COMPUTER.— The digital computer
processes the applied digital data in three phases.
After the three phases are completed, the entire cycle
is repeated. All steps of each phase are performed
sequentially according to a prewired program of
instruction contained in the program. When electrical
power is applied to the digital computer, clock pulses
are generated within the clock generator of the
program.
The clock pulses are distributed by the
control logic to the sequence control, input receivers,
symbol generator, and processor counter. The
processor counter is used to record a specific number
of clock pulses so that the demand-next instruction
(DNI) pulse is not arbitrarily initiated. However, if a
jump signal is received by the function decode, a DNI
pulse is initiated. The jump signal may be repeated
until the correct instruction is selected. When the
DNI pulse is initiated and is in coincidence with a
specific clock pulse in the sequence control, a data
request signal is applied to the program of
instructions.
SYMBOL
GENERATOR.—
The symbol
generator operates in three major modes. The three
modes of operation are the line, circle, and
analog-to-digital conversion (ADC). Each mode is
independently and completely performed before
repeating or starting a different mode. The mode to
be performed is initiated by the function decode in the
digital computer. Correct sequencing of each mode of
operation is provided by the timing pulses from the
control logic section of the digital computer. The
Figure 5-8.-Heads-up display set block diagram.
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