It is the oldest type of CPU which is available and employed in most of the personal and official computers. The single-core CPU can execute only one command at a time and its not efficient in multi-tasking. It signifies that there is a markable declination in performance if more than a single application is executed. If one operation is started, the second process should wait until the first one is finished. But if it is fed with multiple operations, the performance of the computer is drastically reduced.
The performance of a single-core CPU is based on its clock speed by measuring its power. Unlike the CPU with a single core, the processor must switch back and forth within a variable array of data streams and if or more thread is executed, the dual-core CPU manages the multitasking effectively.
To utilize the dual-core CPU effectively, the running programs and operating system should have a unique code called simultaneous multi-threading technology embedded in it. Similar to dual-core CPU, that divides the workload in between the cores, and quad-core enables for effective multitasking. Unless the applications and program executed on it by SMT code will fasten the speed and becomes unnoticeable. Such types of CPU are used in people who need to execute multiple different programs at the same time as gamers, series of supreme commander that is optimized in multiple core CPU.
It is another multiple core processor which is available with six cores and can execute the task which works rapidly than the quad-core and dual-core processors. For users of the personal computer, the processors of Hexacore is simple and now the Intel is launched with Inter core i7 in with Hexa core processor.
But here the users of smartphones use only quad-core and dual-core processors. Nowadays, smartphones are available with hexacore processors. The dual-core is built with two cores, four cores are built-in quad-core, Hexa comes with six cores where the octa processors are developed with eight independent cores to execute an effective task that is efficient and even acts rapidly than quad-core processors.
Trending octa-core processors comprises of a dual set of quad-core processors that divides different activities between the various types. Many times, the minimum powered core sets are employed to produce advanced tasks. If there is any emergency or requirement, the rapid four sets of cores will be kicked in.
How is a computer able to execute the commands that you input? The answer to that question is through the computer's microprocessor. Of course, knowing that doesn't provide much in the way of an explanation. The microprocessor is the central unit of a computer system that performs arithmetic and logic operations, which generally include adding, subtracting, transferring numbers from one area to another, and comparing two numbers.
It's often known simply as a processor, a central processing unit, or as a logic chip. It's essentially the engine or the brain of the computer that goes into motion when the computer is switched on. It's a programmable, multipurpose device that incorporates the functions of a CPU central processing unit on a single IC integrated circuit.
A microprocessor accepts binary data as input, processes that data, and then provides output based on the instructions stored in the memory. The data is processed using the microprocessor's ALU arithmetical and logical unit , control unit, and a register array. The register array processes the data via a number of registers that act as temporary fast access memory locations.
The flow of instructions and data through the system is managed by the control unit. But computer systems aren't the only devices that use microprocessors. Everything from smartphones to household appliances to cars use microprocessors these days. Here are a few reasons why microprocessors are so widely used:. When it comes to discussing microprocessors, their function, and more, you're likely to come across a number of terms that you may not be familiar with. The following are some common terms related to microprocessors:.
Word length refers to the number of bits in the processor's internal data bus--or the number of bits that a processor can process at any given time. For example, an 8-bit processor will have 8-bit registers, an 8-bit data bus, and will perform 8-bit processing at a time.
Simpler models might consist of a few thousand transistors etched onto a chip just a few millimeters square. It has become common to see chips in all kinds of devices with multiple cores, each of which is a processor. To understand how a microprocessor works, it is helpful to look inside and learn about the logic used to create one.
In the process you can also learn about assembly language — the native language of a microprocessor — and many of the things that engineers can do to boost the speed of a processor. A microprocessor executes a collection of machine instructions that tell the processor what to do. Based on the instructions, a microprocessor does three basic things:. There may be very sophisticated things that a microprocessor does, but those are its three basic activities.
The following diagram shows an extremely simple microprocessor capable of doing those three things:. Although they are not shown in this diagram, there would be control lines from the instruction decoder that would:. Coming into the instruction decoder are the bits from the test register and the clock line, as well as the bits from the instruction register.
The previous section talked about the address and data buses, as well as the RD and WR lines. In our sample microprocessor, we have an address bus 8 bits wide and a data bus 8 bits wide.
That means that the microprocessor can address bytes of memory, and it can read or write 8 bits of the memory at a time.
Let's assume that this simple microprocessor has bytes of ROM starting at address 0 and bytes of RAM starting at address ROM stands for read-only memory. A ROM chip is programmed with a permanent collection of pre-set bytes. The address bus tells the ROM chip which byte to get and place on the data bus.
RAM stands for random-access memory. RAM contains bytes of information, and the microprocessor can read or write to those bytes depending on whether the RD or WR line is signaled. One problem with today's RAM chips is that they forget everything once the power goes off. That is why the computer needs ROM. By the way, nearly all computers contain some amount of ROM it is possible to create a simple computer that contains no RAM — many microcontrollers do this by placing a handful of RAM bytes on the processor chip itself — but generally impossible to create one that contains no ROM.
When the microprocessor starts, it begins executing instructions it finds in the BIOS. The BIOS instructions do things like test the hardware in the machine, and then it goes to the hard disk to fetch the boot sector see How Hard Disks Work for details. The microprocessor then begins executing the boot sector's instructions from RAM. The boot sector program will tell the microprocessor to fetch something else from the hard disk into RAM, which the microprocessor then executes, and so on.
This is how the microprocessor loads and executes the entire operating system. Even the incredibly simple microprocessor shown in the previous example has a fairly large set of instructions that it can perform. The collection of instructions is implemented as bit patterns, each one of which has a different meaning when loaded into the instruction register.
Humans are not particularly good at remembering bit patterns, so a set of short words are defined to represent the different bit patterns. This collection of words is called the assembly language of the processor. An assembler can translate the words into their bit patterns very easily, and then the output of the assembler is placed in memory for the microprocessor to execute.
Here's the set of assembly language instructions that the designer might create for the simple microprocessor in our example:. A C compiler translates this C code into assembly language. Assuming that RAM starts at address in this processor, and ROM which contains the assembly language program starts at address 0, then for our simple microprocessor the assembly language might look like this:.
So now the question is, "How do all of these instructions look in ROM? For the sake of simplicity, let's assume each assembly language instruction is given a unique number, like this:.
You can see that seven lines of C code became 18 lines of assembly language, and that became 32 bytes in ROM. The instruction decoder needs to turn each of the opcodes into a set of signals that drive the different components inside the microprocessor.
Let's take the ADD instruction as an example and look at what it needs to do:. Every instruction can be broken down as a set of sequenced operations like these that manipulate the components of the microprocessor in the proper order. Some instructions, like this ADD instruction, might take two or three clock cycles. Others might take five or six clock cycles.
The number of transistors available has a huge effect on the performance of a processor. As seen earlier, a typical instruction in a processor like an took 15 clock cycles to execute. Because of the design of the multiplier, it took approximately 80 cycles just to do one bit multiplication on the With more transistors , much more powerful multipliers capable of single-cycle speeds become possible.
More transistors also allow for a technology called pipelining.
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