Central Processing Unit (CPU)

 

• Control Center of the Computer

• The Brains of the Computer - Responsible for interpreting and issuing instructions to the rest of the computer.

• The Arithmetic/Logic Unit (ALU) is a component of the CPU which performs arithmetic, comparions, and logical operations.

• The CPU completes a set of four basic operations:

• Fetches an instruction

• Decodes the instruction

• Executes the instruction

• Stores the results

 
• The clock synchronizes or controls the timing of all computer operations. The clock speed is measured in megahertz (MHz). The faster the speed of the clock cycle, the more instructions the CPU can execute per second.
 

Input - the flow of information into the computer through the keyboard, mouse, digitizer, scanner, microphone, and other input equipment

Output - the flow of results from the computer going to the monitor, printer, speaker, MIDI instrument, or other output equipment. Some equipment, such as MIDI musical instruments or plotters can be used as input and output devices.

Memory - (Storage) Instructions, data, annd results stored by the CPU until they are needed.

RAM - Random Access Memory - a memory chip that the processor can read from and write to. RAM contents are lost when the computer's power is turned off. Data, instructions, and results are stored temporarily.

ROM - Read-only Memory - a memory chip that can be only be read and used, but not modified. ROM contains a permanent store of instructions for the computer.

 

Communication - Modems, Networks, the Internet, the World Wide Web, FTP (file transfer protocol), etc.

The main printed circuit board in an electronic device, which contains sockets that accept additional boards. 

In a personal computer, the motherboard contains the bus, CPU and coprocessor sockets, memory sockets, keyboard controller and supporting chips.

Chips that control the video display, serial and parallel ports, mouse and disk drives may or may not be present on the motherboard. 

If not, they are independent controllers that are plugged into an expansion slot on the motherboard.