lesson presentation4
DESCRIPTION
System UnitTRANSCRIPT
- is the part of the computer which is responsible for
accepting and processing the data brought in by the input
devices.
- responsible for passing the resulting information to
the users via the output devices.
System Unit
Port is a connection from the main circuit board to a peripheral device such as a keyboard, a printer, or a video monitor.
Expansion card is a printed circuit card with circuitry that gives the computer additional capabilities. Used to connect the following devices to the motherboard such Disk drives, scanners, external CD-Rom, Modems, Audio, TV tuner, and networking.
Central Processing Unit/CPU is an integrated circuit chip containing the electronic circuitry that controls the interpretation and execution of instructions.
1. Control Unit/CU is the part of the CPU that directs the step-by-step operation of the computer.
3 Components of Microprocessor/CPU:
3. Registers are high-speed temporary storage areas which are used to hold both instructions and data during processing.
2. Arithmetic/Logic Unit/ALU is capable of performing arithmetic and logical operations.
1. Instruction Register holds instructions.
3 Types of Registers:
2. Buffer Register temporarily holds data retrieved from the primary memory, prior to processing.
3. Accumulator temporarily stores the results of continuing arithmetic and logical operations.
Computer Memory/Memory used to holds data and instructions before and after they are processed.
1. Read-Only Memory/ROM where permanent instructions are stored.
2 Classifications of Memory:
2. Random-Access Memo/RAM where data and instructions are temporarily stored.
Kilobytes/Kb. 1 Kb = 1,024 bytes
Gigabytes/Gb. 1Gb=1,073,741,824bytes
Megabytes/Mb. 1 Mb = 1,048,576 bytes
Tetrabytes/Tb. 1Tb=1,099,511,627,7776 bytes
Memory Equivalents:
Cache Memory is a place to keep something safe. Also, a special set of very fast RAM chips used to store data that that the CPU most frequently receives from RAM. These chips are called Static Random-Access Memory/SRAM.
is permanent storage that supplements primary storage, or RAM.
Secondary Storage
a non-volatile storage.
1. Sequential-Access Storage Device is stored and accessed in a set order.
2 Types of Secondary Storage:
Ex.
Reel-to-Reel tapes Quarter-Inch Cartridges/QIC
2. Direct-Access Storage Device, sometimes called Random Access, means that the data stored in a specific location so that any data can be found quickly.
Ex.
Floppy disk
Hard disk drive CD-ROM
Flash drive
Reel-to-Reel Tapes it was backup storage after disk storage was introduced. Tape Cartridges/Quarter-Inch Cartridges have greater capacity than reel-to-reel tapes.
Floppy Disk it is an inexpensive, removable storage device used for storing relatively small amounts of data. Hard Disk Drive are absolutely essential for most business PC applications where large amounts of information are processed. Compact Disk Read-Only Memory/CD-ROM is an optical disk that holds approximately.
• Flash Drive/Universal Serial Bus/USB consists of a flash memory data storage device integrated with a USB (Universal Serial Bus)