Name: Lee Long Kiat KJC0870131
Goh Seng Tong KJC0870547
Tan Vinkeat KJC0870651
Pentium
First Pentium CPU models. The Pentium had an L2 cache from 256KB to 1MB, used a 50, 60, or 66 MHz system bus and contained from 3.1 to 3.3 million transistors built on 0.6 to 0.35 process. Chips were housed in PGA packages.
To improve data transfer rates the size of data bus was increased to 64 bits.
At first Pentium processors featured separate 8 KB code and 8 KB data caches. The size of both data and code L1 caches was doubled in Pentium processors with MMX technology.
Intel Pentium CPU used branch prediction to improve effectiveness of pipeline architecture. Branch prediction was enhanced in Pentium MMX processors.
Many desktop Pentiums could work in dual-processor systems.
To reduce CPU power consumption the core voltage was reduced on all Pentium MMX, and many mobile and embedded Pentium processors.
a problem in the floating point unit that, in rare cases, resulted in reduced precision of division operations
Pentium Pro
Performance with 32-bit code was excellent and well ahead of the older Pentium at the time, by 25-35%; however, the Pentium Pro's 16-bit performance was approximately only 20% faster than a Pentium at running 16-bit code. It was this, along with the Pentium Pro's high price, due in part to the full speed L2 cache, that caused the rather lackluster reception for the chip among many home PC enthusiasts, given the dominance at the time of the 16-bit Windows 3.1x and MS-DOS. Windows 95 had already been released at the time of the introduction of the Pentium Pro, but some parts of Windows 95 itself (for example, USER) were still mostly 16-bit. To truly gain the full advantages of Pentium Pro's architecture, one was forced to run a fully 32-bit OS. Microsoft's only truly 32-bit OS at the time was Windows NT 3.51.
Pentium II
Pentium II has 32KB of L1 cache (16KB each for data and instructions) and has a 512KB of L2 cache on package. The L2 cache runs at ½ the speed of the processor, not at full speed. Nonetheless, the fact that the L2 cache is not on the motherboard, but instead in the chip itself, boosts performance. The original Pentium II was code-named "Klamath". It ran at a paltry 66 MHz bus speed and ranged from 233MHz to 300MHz. In 1998, Intel did some slight re-working of the processor and released "Deschutes". They used a 0.25 micron design technology for this one, and allowed a 100MHz system bus. The L2 cache was still separate from the actual processor core and still ran at only half speed. They would not rectify this issue until the release of the Celeron A and Pentium III. Deschutes ran from 333MHz to up to 450 MHz.
Pentium III
Pentium III It was very similar to the Deschutes Pentium II and used a 0.25 µm CMOS semiconductor process. The only differences were the introduction of SSE and an improved L1 cache controller, which was responsible for the minor performance improvements over the "Deschutes" Pentium IIs. It was first released at speeds of 450 and 500 MHz.
Pentium III variants
Katmai
The first Pentium III variant was the Katmai. It was very similar to the Deschutes Pentium II and used a 0.25 µm CMOS semiconductor process. The Katmai used the same slot based design as the Pentium II but with the newer SECC2 cartridge that allowed direct CPU core contact with the heat sink. This version of Katmai was officially rated for 450 MHz, but often contained cache chips for the 600 MHz model and thus usually was capable of running at 600 MHz.
Coppermine
The second version, Coppermine, or 80526, had an integrated full-speed 256 KiB L2 cache with lower latency and a 256-bit bus, named Advanced Transfer Cache by Intel, which improved performance significantly over Katmai. Under competitive pressure from AMD’s Athlon processor, Intel also re-worked the chip internally, and finally fixed the well known instruction pipeline stalls. The result was a remarkable 30% increased performance in some applications where these stalls happened.
Coppermine-T
This revision is an intermediate step between Coppermine and Tualatin, with support for lower-voltage system logic present on the latter but core power within previously defined voltage specs of the former so it could work in older system boards.
Intel used the latest Copper mines with the cD0-Stepping and modified them so that they worked with low voltage system bus operation (GTL) at 1.25 V AGTL as well as normal 1.5 V AGTL+ signal levels, and would auto detect differential or single-ended clocking. This modification made them compatible to the latest generation Socket-370 boards supporting FC-PGA2 packaged CPUs while maintaining combatility to the older FC-PGA boards. The Coppermine-T was also two way symmetrical multiprocessing capable but only in FC-PGA2 boards.
The Coppermine-T is the only Coppermine to feature an integrated heat spreader.
Tualatin
The third revision, Tualatin (80530), was a trial for Intel's new 0.13 µm process. Tualatin-based Pentium III CPUs can usually be visually distinguished from Coppermine-based processors by the metal integrated heat-spreader (IHS) fixed on top of the package. However, the very last models of Coppermine Pentium IIIs also featured the IHS — the heat spreader is actually what distinguishes the FC-PGA2 package from the FC-PGA — both are for Socket 370 motherboards. It was sometimes difficult to install a heatsink on a Pentium III. One had to be careful to not put force on the core at an angle because doing so would cause the edges and corners of the core to crack and could destroy the CPU. It was also sometimes difficult to achieve a flat mating of the CPU and heatsink surfaces, a factor of critical importance to good heat transfer.
Pentium 4
The Pentium 4 brand refers to Intel's line of single-core mainstream desktop and laptop central processing units. The Pentium 4 has an IHS (Integrated Heat Spreader) that prevents the CPU core from accidentally getting damaged when mounting and unmounting cooling solutions. Intel Pentium 4 microprocessors were based on completely new NetBurst micro-architecture, that differed significantly from P6 micro-architecture used in Pentium II/Pentium III microprocessor families. One of key features of Pentium 4 processor was Hyper-Pipelined Technology - 20-stage pipeline, which was two times longer than in previous generation of Pentium processors.
Willamette
Willamette core was expected to operate at frequencies of around 1 GHz, maximum. However, Willamette release delays saw the introduction of the Pentium III prior to its completion. Since the radical differences in these architectures meant Intel could not market Willamette as a Pentium III, it was named Pentium 4. This Pentium 4 was produced using a 0.18 micrometer (180 nm) process and initially used Socket 423, with later revisions moving to Socket 478. These variants were identified by the Intel product codes 80528 and 80531 respectively.
Northwood
Northwood core at 1.6, 1.8, 2.0 and 2.2 GHz. Northwood (product code 80532) combined an increase in the secondary cache size from 256 KiB to 512 KiB (increasing the transistor count to 55 million, up from 42 million) with a transition to a new 130 nm (0.13 micrometer) fabrication process. By making the chip out of smaller transistors, chips can run at higher clocks or at the same speed while producing less heat. Overclocking early stepping Northwood cores yielded a startling phenomenon. When core voltage (Vcore) was increased past 1.7 V, the processor would slowly become more unstable over time, before dying and becoming totally unusable. This became known as Sudden Northwood Death Syndrome, which is caused by
electromigration.
Gallatin (Extreme Edition)
A slight performance increase was achieved in late 2004 by increasing the bus speed from 800 MT/s to 1066 MT/s. Only one Gallatin-based chip at 3.46 GHz was released before the Extreme Edition was migrated to the Prescott core. The new 3.73 GHz Extreme Edition had the same features as a 6x0-sequence Prescott 2M, but with a 1066 MT/s bus. In practice however, the 3.73 GHz Extreme Edition almost always proved to be slower than the 3.46 GHz version.The 'Pentium 4 Extreme Edition' should not be confused with a similarly-named later model, the 'Pentium Extreme Edition', which is based on the dual-core Pentium D.
Prescott
Prescott the core used a 90 nm process for the first time, and "[it] is also a major reworking of the Pentium 4's microarchitecture—major enough that some analysts are surprised Intel didn't opt to call this processor the Pentium 5". Although a Prescott clocked at the same rate as a Northwood, benchmarks show that a Northwood performed slightly better than a Prescott in gaming applications. However, with video editing and other multimedia software, the Prescott's extra cache and SSE3 instructions give it a clear clock-for-clock advantage over the Northwood. The Prescott architecture allows it to be easily set at higher clock-rates. The fastest mass-produced Prescott-based processor was clocked at 3.8GHz.
Pentium D
Smithfield and Presler are the different in Pentium D. The each CPU of Pentium D comprised two single-core dies (CPUs) - next to each other - in one Multi-Chip Module package. For the Pentium D Smithfield Core, Intel produce the different multi-core processor . It added XD-Bit and new technologies to lower temperatures (C1E & TM2). Then, added EIST (Enhanced Intel Speed Step) technology for even better thermal properties as well as EMT64 support for next generation 64-bit applications. added EIST (Enhanced Intel Speed Step) technology for even better thermal properties as well as EMT64 support for next generation 64-bit applications. If do the comparison to Pentium Dual-Core, added EIST (Enhanced Intel Speed Step) technology for even better thermal properties as well as EMT64 support for next generation 64-bit applications.
Pentium Dual-Core
For more than a year now the enthusiast community has been hearing the benefits of dual core processors. AMD was the first to announce their move to a dual core solution, and much was made of them beating Intel to tape, only one problem... On April 4th, 2005 Intel made it clear to the whole industry that they have dual core ready and will be launching parts this quarter. For more than a year now the enthusiast community has been hearing the benefits of dual core processors. AMD was the first to announce their move to a dual core solution, and much was made of them beating Intel to tape, only one problem... On April 4th, 2005 Intel made it clear to the whole industry that they have dual core ready and will be launching parts this quarter. Compare to Pentium D, it can clearly be seen when comparing the specification to the Pentium D series. For example, the Pentium Dual Core has a maximum of 1MB of L2 Cache while the Pentium D processors can have up to 4MB of L2 Cache. But the major difference is the Pentium Dual Core processors only consume 65W peak while the Pentium D consumes a considerable 130W peak consumption which shows its relation to the Core power saving technology. Despite having a smaller L2 cache, the Pentium dual-core has proven to be much faster than the Pentium D under a variety of CPU intensive applications.
AMD Processor
Athlon
Athlon is the brand name applied to a series of different x86 processors designed and manufactured by AMD. The original Athlon, or Athlon Classic, was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intel's competing processors for a significant period of time. AMD has continued the Athlon name with the Athlon 64, an eighth-generation processor featuring x86-64 (later renamed AMD64) technology. Athlon is the brand name applied to a series of different x86 processors designed and manufactured by AMD. The original Athlon, or Athlon Classic, was the first seventh-generation x86 processor and, in a first, retained the initial performance lead it had over Intel's competing processors for a significant period of time. AMD has continued the Athlon name with the Athlon 64, an eighth-generation processor featuring x86-64 (later renamed AMD64) technology. Athlon's CISC to RISC decoder triplet could potentially decode 6 x86 operations per clock, although this was somewhat unlikely in real-world use.
Difference between AMD and Pentium
One of the difference between the AMD and Pentium is AMD run a bit faster than Pentium. AMD are difficult to do overclocking. Pentium are more less expensive to AMD. AMD are no hyperthreading capabilities. Pentium uses more power than AMD and slightly less audio capabilities, video capabilities and capabilities with Maxon cinema software than AMD. And then, AMD Athlons do run more hotter than Pentium 3 and4. AMD processors are more fragile. Unlike the Pentium 4, there is no heatplate to distribute the force applied by the clipping mechanisms of most heatsinks. The horror stories of cracked Athlons are true.
AMDAdvantages It uses less power than two coupled single core processors. This is because there is more power required to send the signals to an external chip and the smaller chip allows the cores to operate at lower power It runs a bit faster than the Pentium It has wide memory bandwidth It uses less power than the Pentium models It has slightly better audio capabilities than Pentium It has slightly better video capabilities than Pentium It has slightly better capabilities with Maxon cinema software than PentiumDisadvantages It makes it harder to do overclocking It has no hyperthreading capabilities It is a bit more expensive than Pentium
PentiumAdvantages It uses less power than two coupled single core processors. This is because there is more power required to send the signals to an external chip and the smaller chip allows the cores to operate at lower power It is less difficult to do overclocking It is less expensive than an AMD It has wide memory bandwidth It has hyperthreading capabilities
Disadvantages It uses more power than the AMD models It has slightly less audio capabilities than AMD It has slightly less video capabilities than AMD It has slightly less capabilities with Maxon cinema software than AMD
Tuesday, August 19, 2008
evolution of computer
Name: Lee Long Kiat
Metric .no: KJC0870131
Course code: CMB1003
Course Name: Computer Organization and Architecture
Section Number: 2
Date of Submission:19/8/2008
Assignment 1: The evolution of computer
· From 1945 to 2008, the generation of computer had been developed to fourth generation. The information below show that the information of every generation computer.
First generation -------vacuum tubes 1946-1958 (The Vacuum Tube Years)
First Generation computers are characterized by the use of vacuum tubes. ENIAC it means Electronic Numerical Integrator And Computer. The first vacuum tube computer, ENIAC, was developed by US army ordinance to calculate ballistic firing tables in World War II. The machine weighed 30 tons, covered about 1000 square feet of floor, and consumed 130 or 140 kilowatts of electricity. It programmed manually by switches.
The vacuum tubes computer is huge machine contents thousand of vacuum tubes. It needs a big room to content itself. It was very huge, slow, expensive, and often undependable. As we can see that the vacuum tubes are very easy overheating.
This is a vacuum tube which is overheating. Leaving a black stain on the inside of the glass tube. Constant overheating and burnout in the vacuum tubes of ENIAC, the first electronic computing device, in 1947 led AT&T Bell Telephone Laboratory engineers John Bardeen, William Shockley, and Walter Brattain to seek out a suitable alternative for the commercially unreliable vacuum tube. As we can know that this is the weakness of the vacuum tube computer.
Second generation-------transistor 1959-1964 (The Era of the Transistor)
In 1947 three scientists, John Bardeen, William Shockley, and Walter Brattain working at AT&T's Bell Labs invented what would replace the vacuum tube forever. This invention was the transistor which functions like a vacuum tube in that it can be used to relay and switch electronic signals.
The difference between first generation and second generation computer:
First generation—vacuum tube
Second generation-transistor
Process speed
Slow
fast
Weight
Heavy
Light
Size
Large
small
Overheating
Yes
no
Replacement cost
expensive
cheap
Compare
1 transistor = 40 vacuum tubes
Table 1
As we can see from the table 1, the comparison of both computers we know that the qualification of second generation computer is better than the first generation computer.
It got more complex arithmetic and logic unit (ALU) and control unit (CU), so it got condition to do high level programming languages, such as early versions of COBOL and FORTRAN.
Second generation computer is the first computer that store their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
Transistor
Transistor is made from the silicon. It is a abundant material can be find in beach sand and glass easily. Therefore it is very cheap to produce the transistor. The transistor was found to conduct electricity faster and better than vacuum tubes.
Third generation -------Integrated Circuit 1965-1970 (Integrated Circuits - Miniaturizing the Computer)
Transistors were a tremendous breakthrough in advancing the computer. In third generation computer the transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. This is a big change in the computer technology, because the size becomes smaller than the second generation computer.
Chip
A chip is a small piece of semiconducting material (usually silicon) on which an integrated circuit is embedded. It can contents about thousand up to millions of transistor onto the silicon of water.
Compare with previous 2 generation computer
Third generation computer
Previous generation computer
Function
Many
less
Size
tiny
huge
Produce cost
cheap
expensive
Speed
fast
slow
The function of the integrated circuit computer:
· Data storage-provided by memory cells
· Data processing-provided by gates
· Data movement-the paths between components that are used to move data
· Control-the paths between components that carry control signals
The function shows at top that mean the third generation is nearly similar with our PC now.
These third generation computers could carry out instructions in billionths of a second. The size of these machines dropped to the size of small file cabinets. Yet, the single biggest advancement in the computer era was yet to be discovered.
Fourth generation-------microprocessors 1971-Today (The Microprocessor)
The computer development came to this generation the computer become smaller and light.
This generation can be characterized by both the jump to monolithic integrated circuits (millions of transistors put onto one integrated circuit chip) and the invention of the microprocessor (a single chip that could do all the processing of a full-scale computer). By putting millions of transistors onto one single chip more calculation and faster speeds could be reached by computers. Because electricity travels about a foot in a billionth of a second, the smaller the distance the greater the speed of computers.
However what really triggered the tremendous growth of computers and its significant impact on our lives is the invention of the microprocessor. Ted Hoff, employed by Intel (Robert Noyce's new company) invented a chip the size of a pencil eraser that could do all the computing and logic work of a computer. The microprocessor was made to be used in calculators, not computers. It led, however, to the invention of personal computers, or microcomputers.
Intel's superscalar successor to the 486 was introduced on March 22,1993. It has two 32-bit 486-type integer pipelines with dependency checking. It can execute a maximum of two instructions per cycle. It does pipelined floating-point and performs branch prediction. It has 16 kilobytes of on-chip cache, a 64-bit memory interface, 8 32-bit general-purpose registers and 8 80-bit floating-point registers. It is built from 3.3 million transistors on a 262.4 square mm die with ~2.3 million transistors in the core logic. Its clock rate is 66MHz, heat dissipation is 16W. In burst mode, the Pentium loads 256 bits of data into its 16K on-board cache in one clock cycle. It is called "Pentium" because it is the fifth in the 80x 86 lines. It would have been called the 80586 had a US court not ruled that you can't trademark a number. The successors are the Pentium Pro and Pentium II. A floating-point division bug was discovered in October 1994.
Metric .no: KJC0870131
Course code: CMB1003
Course Name: Computer Organization and Architecture
Section Number: 2
Date of Submission:19/8/2008
Assignment 1: The evolution of computer
· From 1945 to 2008, the generation of computer had been developed to fourth generation. The information below show that the information of every generation computer.
First generation -------vacuum tubes 1946-1958 (The Vacuum Tube Years)
First Generation computers are characterized by the use of vacuum tubes. ENIAC it means Electronic Numerical Integrator And Computer. The first vacuum tube computer, ENIAC, was developed by US army ordinance to calculate ballistic firing tables in World War II. The machine weighed 30 tons, covered about 1000 square feet of floor, and consumed 130 or 140 kilowatts of electricity. It programmed manually by switches.
The vacuum tubes computer is huge machine contents thousand of vacuum tubes. It needs a big room to content itself. It was very huge, slow, expensive, and often undependable. As we can see that the vacuum tubes are very easy overheating.
This is a vacuum tube which is overheating. Leaving a black stain on the inside of the glass tube. Constant overheating and burnout in the vacuum tubes of ENIAC, the first electronic computing device, in 1947 led AT&T Bell Telephone Laboratory engineers John Bardeen, William Shockley, and Walter Brattain to seek out a suitable alternative for the commercially unreliable vacuum tube. As we can know that this is the weakness of the vacuum tube computer.
Second generation-------transistor 1959-1964 (The Era of the Transistor)
In 1947 three scientists, John Bardeen, William Shockley, and Walter Brattain working at AT&T's Bell Labs invented what would replace the vacuum tube forever. This invention was the transistor which functions like a vacuum tube in that it can be used to relay and switch electronic signals.
The difference between first generation and second generation computer:
First generation—vacuum tube
Second generation-transistor
Process speed
Slow
fast
Weight
Heavy
Light
Size
Large
small
Overheating
Yes
no
Replacement cost
expensive
cheap
Compare
1 transistor = 40 vacuum tubes
Table 1
As we can see from the table 1, the comparison of both computers we know that the qualification of second generation computer is better than the first generation computer.
It got more complex arithmetic and logic unit (ALU) and control unit (CU), so it got condition to do high level programming languages, such as early versions of COBOL and FORTRAN.
Second generation computer is the first computer that store their instructions in their memory, which moved from a magnetic drum to magnetic core technology.
Transistor
Transistor is made from the silicon. It is a abundant material can be find in beach sand and glass easily. Therefore it is very cheap to produce the transistor. The transistor was found to conduct electricity faster and better than vacuum tubes.
Third generation -------Integrated Circuit 1965-1970 (Integrated Circuits - Miniaturizing the Computer)
Transistors were a tremendous breakthrough in advancing the computer. In third generation computer the transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. This is a big change in the computer technology, because the size becomes smaller than the second generation computer.
Chip
A chip is a small piece of semiconducting material (usually silicon) on which an integrated circuit is embedded. It can contents about thousand up to millions of transistor onto the silicon of water.
Compare with previous 2 generation computer
Third generation computer
Previous generation computer
Function
Many
less
Size
tiny
huge
Produce cost
cheap
expensive
Speed
fast
slow
The function of the integrated circuit computer:
· Data storage-provided by memory cells
· Data processing-provided by gates
· Data movement-the paths between components that are used to move data
· Control-the paths between components that carry control signals
The function shows at top that mean the third generation is nearly similar with our PC now.
These third generation computers could carry out instructions in billionths of a second. The size of these machines dropped to the size of small file cabinets. Yet, the single biggest advancement in the computer era was yet to be discovered.
Fourth generation-------microprocessors 1971-Today (The Microprocessor)
The computer development came to this generation the computer become smaller and light.
This generation can be characterized by both the jump to monolithic integrated circuits (millions of transistors put onto one integrated circuit chip) and the invention of the microprocessor (a single chip that could do all the processing of a full-scale computer). By putting millions of transistors onto one single chip more calculation and faster speeds could be reached by computers. Because electricity travels about a foot in a billionth of a second, the smaller the distance the greater the speed of computers.
However what really triggered the tremendous growth of computers and its significant impact on our lives is the invention of the microprocessor. Ted Hoff, employed by Intel (Robert Noyce's new company) invented a chip the size of a pencil eraser that could do all the computing and logic work of a computer. The microprocessor was made to be used in calculators, not computers. It led, however, to the invention of personal computers, or microcomputers.
Intel's superscalar successor to the 486 was introduced on March 22,1993. It has two 32-bit 486-type integer pipelines with dependency checking. It can execute a maximum of two instructions per cycle. It does pipelined floating-point and performs branch prediction. It has 16 kilobytes of on-chip cache, a 64-bit memory interface, 8 32-bit general-purpose registers and 8 80-bit floating-point registers. It is built from 3.3 million transistors on a 262.4 square mm die with ~2.3 million transistors in the core logic. Its clock rate is 66MHz, heat dissipation is 16W. In burst mode, the Pentium loads 256 bits of data into its 16K on-board cache in one clock cycle. It is called "Pentium" because it is the fifth in the 80x 86 lines. It would have been called the 80586 had a US court not ruled that you can't trademark a number. The successors are the Pentium Pro and Pentium II. A floating-point division bug was discovered in October 1994.
Friday, August 1, 2008
forum
Memory Buffer Register
The memory buffer register is located in the centre processor.
It can store the data which is being transferred to and from the immediate access store.
It just works like buffer to let the centre processor and memory act independently without being affected by minor differences in operation. In other words, the data item can store in there for prepare either process in the centre processor or store directly in the memory unit.
Memory Address Register
The Memory Address Register is half of a minimal interface between and computer storage.
It holds the next address of memory location where the first instruction is being executed.
Explain in simplify, when the first instruction is executed and it hold the next address of memory location. After the first instruction has been completed the computer CPU will use the address bus to communicate which memory address it wants to access, then and the memory controller reads the address and then puts the data stored in that memory address back onto the address bus for the CPU to use.
Instruction Register
Instruction register is a part of CPU’s control unit which stores the instruction currently being executed. In a simple processor it loads every instruction to be executed and hold it while is decoded, prepared and ultimately executed.
Instruction Buffer Register
The instruction buffer register is employed to hold temporarily the right hand instruction from a word in memory.
Program Counter
The program counter, or shorter PC (also called the instruction pointer, part of the instruction sequencer in some computers) is a register in a computer processor which indicates where the computer is in its instruction sequence. Depending on the details of the particular machine, it holds either the address of the instruction being executed, or the address of the next instruction to be executed. The program counter is automatically incremented for each instruction cycle so that instructions are normally retrieved sequentially from memory. Certain instructions, such as branches and subroutine calls and returns, interrupt the sequence by placing a new value in the program counter.
Accumulator
In a computer's central processing unit (CPU), an accumulator is a register in which intermediate arithmetic and logic results are stored. Without a register like an accumulator, it would be necessary to write the result of each calculation (addition, multiplication, shift, etc.) to main memory, perhaps only to be read right back again for use in the next operation. Access to main memory is slower than access to a register like the accumulator because the technology used for the large main memory is slower (but cheaper) than that used for a register.
Multiplier Quotient
The multiplier-quotient unit is similar to factor storage units and, in addition, it may be used to store the multiplier factor when multiplying or to develop the quotient when dividing.
The memory buffer register is located in the centre processor.
It can store the data which is being transferred to and from the immediate access store.
It just works like buffer to let the centre processor and memory act independently without being affected by minor differences in operation. In other words, the data item can store in there for prepare either process in the centre processor or store directly in the memory unit.
Memory Address Register
The Memory Address Register is half of a minimal interface between and computer storage.
It holds the next address of memory location where the first instruction is being executed.
Explain in simplify, when the first instruction is executed and it hold the next address of memory location. After the first instruction has been completed the computer CPU will use the address bus to communicate which memory address it wants to access, then and the memory controller reads the address and then puts the data stored in that memory address back onto the address bus for the CPU to use.
Instruction Register
Instruction register is a part of CPU’s control unit which stores the instruction currently being executed. In a simple processor it loads every instruction to be executed and hold it while is decoded, prepared and ultimately executed.
Instruction Buffer Register
The instruction buffer register is employed to hold temporarily the right hand instruction from a word in memory.
Program Counter
The program counter, or shorter PC (also called the instruction pointer, part of the instruction sequencer in some computers) is a register in a computer processor which indicates where the computer is in its instruction sequence. Depending on the details of the particular machine, it holds either the address of the instruction being executed, or the address of the next instruction to be executed. The program counter is automatically incremented for each instruction cycle so that instructions are normally retrieved sequentially from memory. Certain instructions, such as branches and subroutine calls and returns, interrupt the sequence by placing a new value in the program counter.
Accumulator
In a computer's central processing unit (CPU), an accumulator is a register in which intermediate arithmetic and logic results are stored. Without a register like an accumulator, it would be necessary to write the result of each calculation (addition, multiplication, shift, etc.) to main memory, perhaps only to be read right back again for use in the next operation. Access to main memory is slower than access to a register like the accumulator because the technology used for the large main memory is slower (but cheaper) than that used for a register.
Multiplier Quotient
The multiplier-quotient unit is similar to factor storage units and, in addition, it may be used to store the multiplier factor when multiplying or to develop the quotient when dividing.
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