CSE Corner

In this type of CPU organization, the accumulator register is used implicitly for processing all instructions of a program and store the results into the accumulator. The instruction format that is used by this CPU Organisation is One address field. Instruction are fetched by the program control unit.Whose main register is the program counter PC . They are executed in the data processing unit with containing an n-bit (ALU) and 2 data register AC and DR . Most instructions perform operations of the form x1=f i (x 1 ,x 2 ) Memory address are stored in two address register in the PCU .Those are PC and AR . Quote: “There is nothing more dreadful than the habit of doubt. Doubt separates people. It is a poison that disintegrates friendships and breaks up pleasant relations. It is a thorn that irritates and hurts; it is a sword that kills.” ― Buddha Siddhartha Guatama Shakyamuni

In general functions of CPU : To carry out processing To perform arithmetic calcualtion such as addition,subtraction To communicate with peripheral devices using system bus To give commands to all parts of the computer system To control the timing of information flow To control the storage of data or instruction Quote: “All of the great leaders have had one characteristic in common: it was the willingness to confront unequivocally the major anxiety of their people in their time. This, and not much else, is the essence of leadership.”” – John Kenneth Galbraith

When an interrupt is pending the processor does the following thing: It suspends the execution of current program being executed and saves its context.This means saving the address of the next instruction to be executed and any other data relevant to the processors current activity. It sets the program counter to the starting address of an interrupt handler routine. Quote: “I'm selfish, impatient and a little insecure. I make mistakes, I am out of control and at times hard to handle. But if you can't handle me at my worst, then you sure as hell don't deserve me at my best.” ― Marilyn Monroe

DMA means Direct Memory Access ,When large amount of data are to be moved,a more efficient technique is DMA.Block of data are transferred between an external device and the main memory,without continuous intervention by the processor. DMA channels are used to communicate data between the peripheral device and the system memory Without the DMA channels, the CPU copies every piece of data using a peripheral bus from the I/O device. Using a peripheral bus occupies the CPU during the read/write process and does not allow other work to be performed until the operation is completed. With DMA, the CPU can process other tasks while data transfer is being performed. The transfer of data is first initiated by the CPU. During the transfer of data between the DMA channel and I/O device, the CPU performs other tasks. When the data transfer is complete, the CPU...

Associative memory in computer organization is when memory is accessed through content rather than through a specific address. Associative memory is also known as associative storage, associative array or content-addressable memory. Advantages : This is suitable for parallel searches. It is also used where search time needs to be short. It is very high speed searching application. Disadvantages : Associative memory is more expensive than a random access memory. Each cell must have an extra storage capability as well as logic circuits for matching its contents with an external arguement. Usually associative memories are used in applications where the search time is very critical and must be very short. ...

Memory Access time is how long it takes for a character in memory to be transferred to or from the memory. The memory access time depends on: the design of the memory hierarchy The size of blocks at each level The rules chosen to manage each level The time to access information at each level Quote: “Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover.” ― H. Jackson Brown Jr., P.S. I Love You

Flash memory is an electronic (solid-state) non-volatile computer storage medium that can be electrically erased and reprogrammed. Flash memory retains data for an extended period of time whether a flash equipped device is powered on or off. Quote: “I can’t give you a sure-fire formula for success, but I can give you a formula for failure: try to please everybody all the time.” -Herbert Bayard Swope

Memory is any physical storage device that is capable of storing information temporarily basis for use in a computer or other digital storage device. For example : Random Access Memory(RAM) is a volatile memory that stores information on an integrated circuit used by operating system ,software and hardware. Quote: Believe in yourself, take on your challenges, dig deep within yourself to conquer fears. Never let anyone bring you down. You got to keep going...|| Failure will never overtake me if my determination to succeed is strong enough. || As I look back on my life,I realize that every time I thought I was being REJECTED from something good, I was actually being RE-DIRECTED to something better...||

Free Discussion If the instruction processing is split into 6 phases then the pipelined CPU will have 6 different stages for the execution of the sub phases. The six stages are as follows : Fetch Instruction : Instruction are fetched from the memory into a temporary buffer before it gets executed. Decode Instruction : The intstruction is decoded by the CPU so that the necessary OP codes and operands can be determined . Calculate Operand : It is based on the addressing scheme used, either operands are directly provided in the instruction or the effective address has to be calculated. Fetch Operand : Once the address is calculated,the operands need to be ...

Free Discussion Instruction : Instruction is command which is given by user to computer.Computer instruction is a set of steps or documentation that include information or how to operate, performs or maintain particular computer software or hardware . First of all both of the program that acts upon the data are loaded into main memory (RAM) by operating system. Then the 'CPU carries out' is to fetch some data and instruction from main memory then store them in its own temporary memory areas,, this is called fetch. The next step is for the CPU to make sense of the instruction it has just fetched. The CPU is designed to understand a specific set of CPU commands. These are called ...

Free Discussion Instruction is command which is given by user to computer.The processing required for a single instruction is called an instruction cycle.The time period during which one instruction is fetched from memory and executed when a computer is given an instruction in machine language.There are typically 4 stages of an instruction cycle that the CPU carries out : Fetch the instruction from memory. This step brings the instruction into the instruction register,a circuit that holds the instruction so that it can be decoded and executed. Decode the instruction. Read the effective address from memory if the instruction has an indirect address. Execute the inst...

An interrupt is a signal from a device attached to a computer or from a program within the computer that requires the operating system to stop and figure out what to do next. Interrupt is a signal which has highest priority from hardware or software which processor should process its signal immediately. Although, interrupts have highest priority than other signals, there are many types of interrupts but basic types of interrupts are : 1. Hardware Interrupts : If the signal for the processor is from external device or hardware then then it is called Hardware interrupt For example: from keyboard we will press the key to do some action ..this pressing of key in keyboard will generate a signal which is given to the processor to do actio...

Operand : Operand is a term, used to describe any object that is capable of being manipulated. For example : in "1+2", the "1" and "2" are the operands. Operator : Operator is an object that is capable of manipulating a value. For example: in "1+2" the "+" symbol is the operator. Instructions : Instructions are the operations performed by the CPU. Addresses : Addresses are the locations in memory of specified data. Unfamiliar Word Meaning in Bangla Manipulate : নিপূণভাবে ব্যবহার করা Quote : Where there is a will, there is a way. If there is a chance in a million that you can do something, anything, to keep what you want from ending, do it. ...

Unit : This unit receives both data and program statements to function properly and be able to solve problems feeding data and programs. Example:Keyboard,Mouse,Scannar,Printer etc. Memory Unit : The computer memory is a temporary storage area. It holds the data and instructions that the Central Processing Unit (CPU) needs. Before a program can run, the program is loaded from some storage medium into the memory. This allows the CPU direct access to the program. Memory is needed in all computers Central Processing Unit(CPU) : The brain of a computer system is the central processing unit(CPU). The central processing unit (CPU) is the unit which performs most of the processing inside a computer. To control instru...

Pipelining is an implementation technique where multiple instructions are overlapped in execution. The computer pipeline is divided in stages. Each stage completes a part of an instruction in parallel. All the common steps involved in instruction processing by the CPU can be pipelined: Instruction Fetching -[IF] Instruction Decoding -[ID] Operand Loading -[OL] Execution -[EX] Operand Storing -[OS] A pipelined system is often compared to an assembly line on which many products are in various stages of manufacture at the same time. In a non-pipelined CPU, instructions are exexuted in strict sequence. Pipelining permits the situation shown in figure where each major step of instruction processing is assigned to,handled independently by, a separate subunit of the CPU pipeline. ...

In simple words primary memory is the storage device that is directly connected to the CPU and store data temporarily during execution. It implies CPU can directly access primary storage and stores instruction and data for execution or processing. The most popular example of this kind of memory is the RAM that we use in modern day computers. CPU registers, Caches and other memories connected to the CPU local bus falls in this category. Primary storage devices are comparatively faster than all other kinds of memory type. Usually primary storage devices are considered to be directly connected to the processor but in reality modern computers employ components like Virtual memory manager , DRAM controllers etc. In between processor and memory but the notion of direct connection is still valid since these components are transparent to ...