DR Von Neumann’s Computer –(4)

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After all standard “instructions”

Contained in the program

Are typed in by human engineer

(Onto the main memory

By means of a key board)

Are fully implemented

And final answer is finally worked out

(All this takes only a billionth of a second)

It is first kept in prescribed memory house

On the main memory board for a billionth of a second

And then sent to the out putting unit

Under orders of the versatile CPU.

Remember here that all the inputted “instructions”

In their standardized form

Are first converted to 010101 code

Letter by letter, number by number

And each symbol like comma and question mark

One after one carefully

Before being sent to main memory board.

Now about the second part of the instruction

Which is sent by DR to the IBR for safe custody

(The safe custody is only for a millionth of second.

But it is too long a time in the world of CPU and ALU!)

IBR which we know had twenty flip flop chambers

Is also divided by the internal electric circuits

Into an eight bit and a twelve bit parts.

The eight bit part denotes the binary code of the

Mathematical circuit to be switched on in ALU

For doing the mathematical operation

On the second part of instruction

Contained in the “forty bit combined instruction”.

This eight bit first part of the second instruction

Is sent to CPU which in its turn

Sends required electric signals to the alu

And switches on “add/subtract/multiply/ divide” circuit.

The remaining twelve bit code is the binary code

Giving the “house number” of memory house

On the main memory board

Where the numbers “to be operated upon”

Are resting before the operation!

(Just as done in the case of the first part)

The register IR supplies this “memory housenumber” .

To the MAR register which points directly

To that particular memory house, you may say.

A signal is given by the MAR to CPU

Which in turn sends the required electric signal

To that particular memory house.

A copy of the number’s eight bit/sixteen bit code travels

Via the superhighways to the ALU

But only after check by the versatile DR register.

All this work is done in a billionth of second

But it is too long a time in the world of CPU and ALU .

One other extremely important register

Called PCensures serial dispatch

Of the “forty bit instructions”

From the main memory board

To the versatile forty bit data register DR.

The PC also readies the address of the “next instruction”

And transfers this address to mar

For linking to the manufacturer’s

Serial number of the memory house

Where the “forty bit next instruction” is stored

Then only the CPU can issue electric signals

To that particular memory house

To immediately send a copy of the “forty bit instruction”

By the forty channel special superhighway

To the very long 40 bit DR register.

We already learnt how the DR

Processes the forty bit instruction.

All this work is done like a clock work

Till all the “forty bit instructions”

Forming the computer program

Are sent to DR register one by one

To be processed in billionth of a second

Under orders of the versatile CPU .

Let us take a long program (like a long algebraic problem)

It has two hundred serially numbered “instructions”, let us say

The CPU processes them in one go

Taking the instructions one by one

(Remember that these instructions

Are orders of the human engineer

In a strict serial arrangement

And in a strictly coded language

That is translated by a special machine into 010101 language

Which only is understood by the computer’s brain

And only then sent to main memory board

And taken from there

Instruction by instruction

By the commander-in- chief the CPU.)

The CPU processes all the hundred instructions

In one go in perhaps a billionth of second

And gives you the final answer in a “jiffy”!

(Has anybody studied the duration of a “jiffy” in seconds?)

This high speed computing became possible

Only after Dr von Neumann proposed the new architecture

In the “ancient times”(the 1940s)

Hats off to von Neumann of immortal fame!


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