Hardware

Lesson 1

Hardware is all of the electronic equipment that a computer includes. If you can touch it, pick it up, or move it around, it is hardware.

A computer consists of a central unit, called the central processing unit (CPU), and external devices, called peripherals.

The central processing unit is the "brain" of the computer. Every instruction given to the computer passes through the electronic circuits of the CPU. When you program the computer to add two numbers together, the arithmetic is performed in the CPU. When you want something sorted, the CPU controls the task from start to finish.

CPU

The system processing unit contains all of the components of the computer system including the central processing unit. The SPU does not refer to the system console or any other single, peripheral device.

SPU

Peripherals are all of the other hardware connected to the CPU. Peripherals are often referred to as peripheral devices.The computer assigns to each device an identifying number called an LDEV number. This number is the "address" (of your terminal, for instance) that the computer uses when it sends and receives information.

Peripherals

Peripherals

There are five classes of peripherals that may be connected to a standard HP 3000

system:

Your terminal (the screen and keyboard) gives you a way of communicating with the computer. You can enter commands or run programs and see the results.

Terminals

Information and programs that are not being used by the SPU are stored on disk drives. The information could be the text of a letter, information in a database, or a program that you might use every day.

There might be one or many disk drives attached to your computer.

Information on a disk drive can be retrieved quickly.

Disk Drives

Information that is not accessed frequently but must be kept for a long time is stored on magnetic tapes. Tape drives are used to store information from the disk onto the tape.

Tape Drives

Printers come in all shapes and sizes. Some are designed for extremely high speeds. Some are designed for very high-quality, finished documents.There may be one or many printers attached to your computer. If there is only one, it may be referred to as the line printer.

Printers

The system console is a special terminal that your system operator uses almost exclusively to control the day-to-day functioning of the computer. The system console is usually located close to the CPU.

System Console

Lesson 1 Exercises

1.What is the name of the central unit of the computer?

1.Name four peripherals that make up a basic HP 3000 system.

1.What is the name of the terminal that is used by the system operator to control the entire HP 3000 system and that is usually located close to the CPU?