A02- Fetch, Execution and IO

 CPU (Central Processing Unit), also called the Processor is the "heart" of the computer.

Data is stored in Bits.

  • One byte is equal to 8 bits.
  • A bit can be either 0 or 1.
  • A pulse of 5 volt of electricity can represent 1 bit and a pulse of 0 volt can represent 0 bit.
  • With fiber optic cable, 1 bit is represented by the presence of light and 0 by the absence of light.
  • ASCII- American Standard Code for Information Interchange
Functional Units

  • Organized into words of typically 32 bits which contains 4 bytes.
Cache Memory
  • Adjunct to the main memory
  • Much smaller and faster than the main memory
  • Holds section of the data currently being executed.
Processor
  • Logic circuits for performing arithmetic and logic operations.
  • Timing and control Circuits for fetching program instructions and data from main memory, one after another
  • Registers (16 or 32), each of which hold one word of operand data sections of the program and data currently being executed.
Processor
Arithmetic and Logic Unit
  • Most computer operations are executed in the ALU of the processor.
Control Unit
  • Memory, ALU and I/O units store and process information and perform input and output operations.
  • Control Unit makes sure that the operations of this unit are coordinated.
  • It also directs all the activities in the computer.
Instruction Cycle or Machine Cycle
  • Computer system derives its power by being able to repeat the basic operations billions of times per second.
  • A single cycle consists of Fetch, Decode, Execute, Memory Access and Write Back phases.
Instruction Type
  • Load: Read a data operand from memory or an input device into the processor.
  • Store: Write a data operant from a processor register to memory or an output device.
  • Operate: Perform an arithmetic or logic operation on data operands in processor register.

Processor components
  • The program counter (PC) register holds the memory address of the instruction. In most processors, the PC is incremented after fetching an instruction, and holds the memory address of (" points to") the next instruction that would be executed.
  • The instruction register (IR) holds the current instruction.
  • General purpose registers hold data and addresses.
  • Control circuits and the arithmetic and logic unit (ALU) fetch and execute instructions.
PC: Program Counter
  • As each instruction gets fetched, the program counter increases its stored value by 1.
  • After each instruction is fetched, the program counter points to the next instruction in the sequence.
  • When the computer restarts or is reset, the program counter normally reverts to 0.
Handling I/O Devices
An application program can:
  1.  Read data from an input device.
  2. Write data to an output display screen.
  3. Sence the readiness of an input or output device to perform a transfer.
Performance
How quickly can program be executed?
  1. Speed of electronic circuits in the processor.
  2. Access time to cache and main memory.
  3. Design of the instruction set.
  4. Number of operations that can be done at the same time (parallelism).
Technology
Improvement in the materials used for transistors means instructions can be executed faster.
Improvement in process technology mean more transistors can be placed on a
chip leading to:
•More logic functionality
•More memory storage capacity
 
You want a fast CPU for the new computer you are building, and your motherboard only has one CPU socket. To increase the processing power, you need a CPU that provides more than one processor. What is this CPU called?
A. multicore 
B. multiple
C. multifaceted
D. multicast.


Comments

Post a Comment

Popular posts from this blog

Topic D02 Introduction to Linux

 Linux is an operating system. An operating system is software that manages all of the hardware resources associated with a desktop or laptop. The OS manages the communication between your software and your hardware. Without the OS, the software would not function. To manage files, we can use two methods: Terminal (Command Line Interface - CLI) File manager (Graphical User Interface-GUI). Some compelling uses of Command Line Interface (CLI): Commands offer more options and are flexible. Some configurations in GUI are 5 screens deep while in CLI it is just a single command. CLI loads fast and do not consume RAM as compared to GUI. There are two ways to launch CLI on Ubuntu: Go to search and type terminal CTRL + ALT + T $ sign suggests that you are working as a regular user in Linux. "#" is displayed while working as a root user. Present Working Directory Directory which is currently browsing is called the Present working directory. if we want to check the directory we are curr...
Read more

EO2-Linux Network and Process Managment

Image
Process A process is a set of instructions that is loaded in a memory.  A process in Linux is nothing but a running program. Each process will have a unique process ID (PID) and other resources, like memory and CPU time. A process can be in only one state at an instance. They can be of the following instances: Running: It is executing the code currently. Ready: It is ready to be executed but is waiting for CPU time. Sleeping: It is temporarily stopped so that other processes are finished first. Stopped: The process is stopped by the system or the user. Zombie: The execution is completed but it still has an entry in the process table. Process Management ps - report a snapshot of the current process. ps -a -- All terminals ps -e -- List of all the processes ps -o --(customer properties) ps -ao --tty, comm, pid, %mem, %cpu top - real-time process monitor that displays the information about all running processes. kill - it is used to stop a process Network Configuration ifconfig o...
Read more

Topic D01- Container Technology

  What are Containers? It can be defined as a standard package of software that bundles the code and all its dependencies so that the application is able to run quickly and reliably from one computing environment to another. It provides an infrastructure that allows application deployment to be packaged lightly and immutably. Container Image- The code, runtime, system tools, system libraries, and settings are packaged together as a container image. Linux Containers Is a set of one or more processes that are isolated from the rest of the system. All the files necessary to run them are provided from a distinct image. Linux containers are portable and consistent as they move from development to testing, and then finally to production. This makes it better to use than most development pipelines.  Linux containers help you alleviate issues and iterate faster—across multiple environments. Why should you use Linux Containers? Imagine you’re developing an application. You do you...
Read more