Studied by 24 people
Computer System
consists of hardware and software components and follow the concept of the input, process, output and storage model
other data needed during the processing phase
exists in the storage of the computer system and will be used during the processing phase.
Central Processing Unit
The brain of a computer, responsible for executing instructions and performing calculations
CPU can only access data in the…
primary memory.
Control Unit
Retrieves instructions from memory, decodes them, and controls the flow of data between the CPU and other components
Memory Address Register
Stores the address of the next instruction or data to be fetched or stored in the memory.
Memory Data Register
Storage location that holds the data being read from or written to the computer's memory. Acts as an interface between the memory and the processor, allowing the processor to access and manipulate data stored in memory
Arithmetic Logic Unit
ALU performs arithmetic and logical operations. CU is responsible for providing the ALU with the data and instructions.
Memory Address/Data Bus
The pathway that carries information between the CPU and memory. It consists of address lines for locating data in memory and data lines for transferring the actual data.
Random Access Memory
Volatile memory for random data access. It stores active data for program execution. MDR transfers data between CPU and RAM.
Read Only Memory
Stores data permanently. Non-volatile. Includes the computer's startup instructions and other essential software. Cannot be modified or written to by normal computer operations.
primary memory
only memory accessible by CPU. Stores in binary. only RAM and ROM
cache memory
Static RAM. Faster, smaller, more expensive. Placed between DRAM and processor. Hold info most often used quickly by the processor.
Machine Instruction Cycle
MEM Fetch → CU Decode → ALU Execute → MEM Store.
Fetching instruction
CPU sends the appropriate address through the memory (address) bus to the primary memory. The instruction that resides in the specific address is then copied into the data bus and sent to the control unit (CU).
Decoding instruction
Done by CU to allow the CPU to be aware of any additional data that is necessary for the execution of the instruction
Execute instruction
ALU executes operations from instruction and calculates a result to store or reprocess with more data
Store result and check for next instruction
Result stored in primary memory by finding an address and placing it there
Secondary Memory
Is a relatively slow memory that may be written to but is also non-volatile. Also known as persistent storage.
Virtual Memory
The process of temporarily loading memory from the ROM to secondary memory to create room for more storage
Operating System
set of software that controls the computer’s hardware resources and provides services for computer programs. intermediary between software applications and the computer hardware.
Services of OS
Peripheral Communication
Memory Management
Security
Networking
Resource Monitoring and multitasking
Disk access and data management
Peripheral Communication
Communicating directly with the hardware outside CPU and providing an interface between hardware devices and applications.
Memory Management
How the memory is used by applications and ensuring that one application does not interfere with memory that is being used by another.
Security
Protection of data on computer, commonly done by user authentication. Additional security measure is use of log files that keep track of any user activity in computer system.
Networking
Connections to and interactions with networks of other computer systems so as to allow the sharing of resources. OS is an intermediary between applications and networks.
Resource Monitoring and Multitasking
The allocation of resources so that an application can run effectively. Applications must share the CPU time in order to accomplish their goal. This is known as multitasking and it is a core OS service.
Disk access and data management
Keeping track of files stored in memory and disks, as well as which files are being used by which applications so that an application does not overwrite another applications‘ files.
Software Applications
Type of computer program that performs a specific personal, educational, or business function
Word Processors
Used for the production of any sort of document. It includes tools for the composition, formatting and possibly printing of documents.
Spreadsheets
Used for the organization and analysis of data. The data in spreadsheet application is represented as cells, organized in rows and columns. Can do operations and make graphs.
Database Management System (DBMS)
It manages (creates, queries, updates, stores, modifies, and extracts information) databases and is designed to provide an interface between users and a database.
Web Browser
Used to access, retrieve, and present content on the World Wide Web. Content may be identified by URL (Uniform Resource Locator)
Allows for the exchange of digital messages from a single author to one or more recipient(s).
Computer Aided Design (CAD)
Assists engineers to create, modify, analyze and optimize a design. Purpose is to increase productivity of the designer and the quality of the resulting design.
Graphic Processing Software
Allows user to manipulate visual images on a computer.
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