Computer Ports and Multi-Media

Computer Ports Computer ports, normally just called ports, are the physical interfaces that connect external components such as monitor, printer, mouse, scanner to the computer. There are different types of computer ports, with majority located on the back of a motherboard, while there are some on the front of most computer cases

Characteristic of Ports External devices are connected to a computer using cables and ports. Ports are slots on the motherboard into which a cable of external device is plugged in. Examples of external devices attached via ports are mouse, keyboard, monitor, microphone, speakers etc.

Classification of Ports There are two classes of ports Serial Parallel. Both are bi-directional, meaning data can be sent and received. Serial ports send information one bit at a time down a single wire. You can look at it like a two-way street. Every car in a lane travels in a single line. A parallel port carries data several bits at once on multiple wires much like vehicles on a multi-lane highway. 

Classification of Ports Serial ports were used for devices that didn’t require speed such as the mouse and keyboards, while parallel ports were used for devices that needed data to be processed much faster, like printers. Many motherboards still have PS 2 ports for a mouse and keyboard which is now obsolete. These are round and color coded. The green one is the mouse connector and the purple for the keyboard. However, many people nowadays use a USB or wireless keyboard and mouse instead. 

Different Types of Ports Network /LAN Port Universal Serial Port Firewire Port Sound Card/Ports Video Port/Port Video Monitors

Local Area Network (LAN) Port: The LAN port is used to connect computers to each other in a network or to the internet through a network card/adaptor. It looks exactly like a regular telephone jack (RJ-11) except it's a little larger and its called RJ-45. Ethernet cable is used for the connection.

Universal Serial Bus The Universal Serial Bus port is a small rectangular port and is the primary way used today to attach all kinds of devices via a USB cable. USB was designed to standardize the connection of computer peripherals such as keyboards, pointing devices, digital cameras, printers, disk drives and network adapters to personal computers both to communicate and to supply electric power. USB has therefore effectively replaced a variety of earlier interfaces, such as serial and parallel ports, as well as separate power chargers for portable devices. 

USB Standards/Technology The USB standards are USB 1.1 (obsolete), 2.0, and 3.0 and the major difference is speed. USB 1.1 could transfer data up to 12 Mbps (megabits per second . USB 2.0, also called High-Speed USB, can transmit at a maximum of 480 Mbps, has 4 wires. USB 2.0 is grey in colour and has a maximum cable length of 5 metres The USB 3.0 standard (USB Super speed), introduced in late 2008, is 10x faster than USB 2.0, with a maximum rate of 4.8 Gbps (gigabits/sec, and is backward compatible with USB 2.0. USB 3.0 is blue in colour and has a maximum cable length of 3 metres

USB Standards USB 3.0 is bidirectional i.e. has full duplex capabilities - send and receive data simultaneously. It has 9 wires and this extra wires make the cable a lot thicker. It increases power output for charging USB devices, allowing you to use more than four devices per hub, and there's no power drain on non-active devices. USB 2.0 is half duplex. 

USB Standard USB devices are hot-swappable, meaning they can be plugged or unplugged without turning off the computer. Another nice feature is that you can attach numerous devices to a computer indirectly i.e., 127 devices can be connected via USB hubs. A USB hub is a small component that contains additional USB ports. You plug it into your computer, and immediately you can connect more devices.

USB Hub

Firewire Port Originally developed by Apple, Firewire is similar to USB and was mainly developed to transmit data between digital devices such as camcorders and video equipments. Firewire is also a competitor with USB and its speeds far surpass those of USB 2.0, making it ideal for transferring large files like audio and video. The first standard, had a data speed up to 400 Mbps and so is known as Firewire 400. The second standard, transfers data at a maximum speed of 800 Mbps and is known as Firewire800. 

Firewire Port and Connectors

Firewire The typical firewire port looks a lot like USB except it's triangular at one end. Like USB, they are hot-swappable, but unlike USB, devices can connect to each other without a computer (called peer to peer). You can also purchase a Firewire hub to attach several devices. A maximum of 63 devices can connect to each other. 

e-SATA eSATA is used to connect a computer to an external hard drive or external optical drive; this method offers much higher transfer rates between devices as compared to USB 2.0, but these devices typically require a standalone power supply

Multimedia Multimedia is defined as the use of computers to present text, graphics, videos and sound in an integrated manner. So no computer is complete without sound, graphics and videos. From listening to our favourite tunes to watching the latest video games and movies, multimedia plays an important role in making this possible. All these are made possible by sound, graphic and video cards. 

Sound Card In the natural world, sound travels in waves. We refer to these waves as analogue. Computers only understand digital, or 1's and 0's. Sound card technology converts analogue sound, such as from a microphone or other source, to digital, then back to analogue for output through speakers or headphones. While being converted to digital, sound effects or other enhancements are added before being sent to speakers

Sound Card A sound card is a printed circuit board that translate analog and digital information. To achieve this, the card uses Analogue to Digital Converter (ADC) and, Digital to Analogue Converter (DAC). In the absence of these two converters the sound card uses a codec (Code and Decode) which is a device used for encoding or decoding a digital data stream or signal

Sound Card Types of Sound Expansion Slots  Industry Standard Architecture (ISA)  Peripheral Component Interconnect (PCI) Interface ISA is now obsolete There are also external sound cards that connect through a USB port. Some people like buying their own card because many of them have more features than what's on a motherboard. But whichever you choose, there are three common ports: Line-In, Line-Out, and Mic. 

Line-In: This port is where sound from an external source enters the card, such as recording from a tape recorder, disc player, audio mixer. On many sound cards this port is light blue. Line-Out (Speaker Out or Front): Where sound is output; usually to headphones or stereo speakers. On many cards this port is lime green. Mic: Microphone port; usually pink.

Sound Card

External Sound Card

Graphics/Video Card A graphics card is what your computer uses to convert data in your machine to useful images on your monitor. Also known as video cards they come in a wide variety of models, with many different options available.

Graphic/Video Card Current video cards are designed for PCI Express slots (Peripheral Component Interconnect) because they provide excellent speed that is needed for today's video games and other applications that require superior video quality. Before PCI Express, AGP (Accelerated Graphics Port) was the main slot used for video cards, but is now too slow for today's standards. AGP slots can still be found on some motherboards, but they are practically obsolete. 

Graphic/Video Card Video cards contain their own processor ( Graphics Processing Unit or GPU), Memory, and BIOS. The GPU carries out all the difficult math calculations to produce images, especially real life-like 3D images like those in video games. They generate lots of heat like a computer CPU and also require a heat sink or fan on them. When it comes to memory, video adapters use a type of DDR called GDDR (the "G" is for graphical) to distinguish it from regular DDR memory used by the PC. Current Graphics card support GDDR3, GDDR4, or GDDR5. These differ in terms of the amount of data transmitted and power usage.  The type of processor technology and amount of memory are two key factors determining video performance.

Digital Video Connectors S-Video Carries only digital video Mobile High Definition Link Connecting mobile devices to TV High Definition Multimedia Interface (HDMI) Carries both digital sound and video on the same cable

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