In this section, we cover the major hardware components of a microcomputer system used for input, output, processing, storage, electrical supply, and communication. Computer repair miami knows that most input and output devices are outside the computer case. Most processing and storage components are contained inside the case. The most important component in the case is the central process- ing unit (CPU), also called the processor or microprocessor. As its name implies, this device is central to all processing done by the computer. Data received by input devices is read by the CPU, and output from the CPU is written to output devices. The CPU writes data and instructions in storage devices and performs calculations and other data processing. Whether inside or outside the case, and regardless of the function the device performs, each hardware input, output, or storage device requires these elements to operate. A method for the CPU to communicate with the device.
The device must send data to and/or receive data from the CPU. The CPU might need to control the device by pass- ing instructions to it, or the device might need to request service from the CPU. Software to instruct and control the device. A device is useless without software to control it. The software must know how to communicate with the device at the detailed level of that specific device, and the CPU must have access to this software in order to interact with the device. Each device responds to a specific set of instructions based on the device’s functions. The software must have an instruction for each possible action you expect the device to accomplish. Electricity to power the device. Electronic devices require electricity to operate. Devices can receive power from the power supply inside the computer case, or they can have their own power supplied by a power cable connected to an electrical outlet. In the next few pages, we take a sightseeing tour of computer hardware, first looking outside and then inside the case.
I’ve tried to keep the terminology and concepts to a minimum in these sections, because in future chapters, everything is covered in much more detail. Most input/output devices are outside the computer case. These devices communicate with components inside the computer case through a wireless connection or through cables attached to the case at a connection called a port. Most computer ports are located on the back of the case, but some cases have ports on the front for easy access. The most popular input devices are a keyboard and a mouse, and the most popular output devices are a monitor and a printer. The keyboard is the primary input device of a computer. The keyboards that are standard today are called enhanced keyboards and hold 104 keys. Ergonomic keyboards are curved to make them more comfortable for the hands and wrists. In addition, some keyboards come equipped with a mouse port used to attach a mouse to the keyboard, although it is more common for the mouse port to be on the computer case.
Electricity to run the keyboard comes from inside the computer case and is provided by wires in the keyboard cable. A mouse is a pointing device used to move a pointer on the screen and to make selections. The bottom of a mouse has a rotating ball or an optical sensor that tracks movement and controls the location of the pointer. The one, two, or three buttons on the top of the mouse serve different purposes for different software. For example, Windows Vista uses the left mouse button to execute a command and the right mouse button to display a shortcut menu of commands related to the item. Computer repair miami use most storage and all processing of data and instructions are done inside the computer case, so before we look at components used for storage and processing, let’s look at what you see when you first open the computer case.
Most computers contain these devices inside the case. A motherboard containing the CPU, memory, and other components, a hard drive and optical drive (CD or DVD) used for permanent storage, a power supply with power cords supplying electricity to all devices inside the case, adapter cards used by the CPU to communicate with devices inside and outside the case, cables connecting devices to adapter cards and the motherboard, some of the first things you’ll notice when you look inside a computer case are adapter cards. An adapter card is a circuit board that holds microchips, or integrated circuits (ICs), and the circuitry that connects these chips. Adapter cards, also called expansion cards or simply cards, are installed in long narrow expansion slots on the motherboard. All adapter cards contain microchips, which are most often manufactured using CMOS (complementary metal-oxide semiconductor) technology. The other major components inside the case look like small boxes and include the power supply, hard drive, CD drive, and possibly a floppy drive. There are two types of cables inside the case: data cables, which connect devices to one another, and power cables or power cords, which supply power. If the cable is flat, it most likely is a data cable.
