Transcript How Micro Processors Works

MICRO-PROCESSORS
Objective
To demonstrate How a Microprocessor do
common calculations and the process involved
in it.
The type of calculations in which normally
my class fellows do big mistakes.
But First Of All
What a Microprocessor is?
• A microprocessor is also known as a CPU or Central Processing unit. It
is a complete computation engine that is fabricated on a single chip.
• The first microprocessor was the Intel’s 4004, introduced in 1971. The
4004 was not very powerful, all it could do was to add and subtract,
and it could only do that four bits at a time. But it was amazing that
everything was on one chip. The 4004 powered one of the first portable
electronic calculators.
• The first Microprocessor to make it into the house was Intel’s 8080, a
complete 8-bit computer on one chip introduced in 1974. The first
microprocessor to make a splash in the real market was the Intel’s 8088,
introduced in 1979 and incorporated into the IBM Pc( which first
appeared in 1982 or so).
In November 1971, Intel introduced the world's first
commercial microprocessor, the 4004, invented by
three Intel engineers. Primitive by today's standards,
it contained a mere 2300 transistors and performed
about 60,000 calculations in a second. Twenty five
years later, the microprocessor is the most complex
mass-produced product ever, with more than 5.5
million transistors performing hundreds of millions of
calculations each second.
• Pressing the 2 key alerts the
microprocessor and signals the Prefetch
Unit to ask the computer's main memory
for a specific instruction on the new data
since there is nothing about it in the
Instruction Cache.
• The new data instruction comes into the
microprocessor through the Bus Unit from
the computer's main memory and gets
stored in the Instruction Cache, where it is
assigned a code "2=X".
• The Prefetch Unit then asks the Instruction
Cache for a copy of the code "2=X" and sends
it to the Decode Unit for further processing.
•
In the Decode Unit the instruction "2=X" is
translated or decoded into a string of binary
code that is sent off to the Control Unit and
the Data Cache to tell them what to do
with the instruction.
•
Because the Decode Unit figured out that
the number 2 was to be stored for the future
in the Data Cache, the Control Unit now
performs the instruction for "2=X." This
causes the number 2 to be sent to an address
in the Data Cache called "X," where you see
it waiting for further orders.
• When you press the 3 key the Pre-fetch
Unit asks the computer's main memory
and the Instruction Cache for specific
instructions on this new data. No
matching instruction is found in the
Instruction Cache so the instruction
will come from the main memory.
• Similar to "2=X," the new data
instructions come into the
microprocessor from the computer's main
memory and get stored in an Instruction
Cache address where it is assigned the
code "3=Y."
• The Prefetch Unit then pulls a copy of the
code "3=Y" from the Instruction Cache and
sends it to the Decode Unit for further
processing.
• In the Decode Unit the instruction "3=Y" is
translated or decoded into a string of binary
code that is sent off to the Control Unit and
the Data Cache to tell them what to do with
the instruction.
• Because the Decode Unit figured out that the
number 3 was to be stored for the future in
the Data Cache, the Control Unit now
performs the instruction for "3=Y." This
causes the number 3 to be sent to an address
in the Data Cache called "Y," where it waits
like the "2" for further orders.
• When you press the "+" key the
Prefetch Unit asks the computer's
main memory and Instruction Cache
for instructions on the new data,
which must be fetched from main
memory
• Because this is a new instruction, the
"+" comes into the microprocessor from
the computer's main memory and gets
stored at an address in the
Instruction Cache as a code "X+Y=Z,"
showing that the act of adding is
going to take place.
• The Prefetch Unit then asks the
Instruction Cache for a copy of the
code "X+Y=Z" and sends it to the
Decode Unit for further processing.
In the Decode Unit, "X+Y=Z" is
translated or decoded and sent off to
the Control Unit and the Data
Cache to tell them what to do with
the instruction - also the ALU is
given a message that an ADD
function will be performed.
• In the Control Unit the code is
broken down and the ADD
command is sent to the ALU
where "X" and "Y" are added
together after they have been
sent up from the Data Cache.
The ALU then talks to its
buddy, the Registers, and sends
the "5" over to be stored in one of
the address locations there.
• When you press the "=" key the
Prefetch Unit once again
checks the Instruction Cache
for an instruction for the new
data, which it doesn't find.
The instruction for "=" comes
into the microprocessor from
the computer's main memory
through the Bus Unit and gets
stored in an Instruction Cache
address as the code "Print Z."
• The Prefetch Unit then asks the
Instruction Cache for a copy of
the code "Print Z" and sends it to
the Decode Unit for further
processing. .
In the Decode Unit the
instruction "Print Z" is
translated or decoded into a
string of binary code that is sent
off to the Control Unit to tell it
what to do with the instruction.
• Now that the value of Z has
been computed, and is residing in
register file entry #5, the print
command has only to retrieve
register 5's contents and display
them to a screen so you can
finally see the sum of 2+3. The
microprocessor has completed its
task for you.
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By: -
Muhammad Zohair Imtiaz.
CSU/F99/113
&
Mujeeb Alam
CSU/F99/121
Special Thanks To The Following.
•My Father Sabir Imtiaz.
•My Chacha Tariq Sarfaraz In US.
•Our friends In Which
•Rafia My Best Friend.
•Ibrahim Aslam(scharique)
.
My Another Best Friend
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