16 Types of Computer Ports and Their Functions

09/10/2020 

A Computer Port is an interface or a point of connection between the computer and its peripheral devices. Some of the common peripherals are mouse, keyboard, monitor or display unit, printer, speaker, flash drive etc.

The main function of a computer port is to act as a point of attachment, where the cable from the peripheral can be plugged in and allows data to flow from and to the device.

A computer port is also called as a Communication Port as it is responsible for communication between the computer and its peripheral device. Generally, the female end of the connector is referred to as a port and it usually sits on the motherboard.

In Computers, communication ports can be divided into two types based on the type or protocol used for communication. They are Serial Ports and Parallel Ports.

A serial port is an interface through which peripherals can be connected using a serial protocol which involves the transmission of data one bit at a time over a single communication line. The most common type of serial port is a D-Subminiature or a D-sub connector that carry RS-232 signals.

A parallel port, on the other hand, is an interface through which the communication between a computer and its peripheral device is in a parallel manner i.e. data is transferred in or out in parallel using more than one communication line or wire. Printer port is an example of parallel port.

The article gives a brief introduction to different types of ports along with their applications.

PS/2

PS/2 connector is developed by IBM for connecting mouse and keyboard. It was introduced with IBM’s Personal Systems/2 series of computers and hence the name PS/2 connector. PS/2 connectors are color coded as purple for keyboard and green for mouse.

PS/2 is a 6-pin DIN connector. The pin out diagram of a PS/2 female connector is shown below.

Even though the pinout of both mouse and keyboard PS/2 ports are same, computers do not recognize the devise when connected to wrong port.

PS/2 port is now considered a legacy port as USB port has superseded it and very few of the modern motherboards include it as a legacy port.

Serial Port

Even though the communication in PS/2 and USB is serial, technically, the term Serial Port is used to refer the interface that is compliant to RS-232 standard. There are two types of serial ports that are commonly found on a computer: DB-25 and DE-9.

DB-25

DB-25 is a variant of D-sub connector and is the original port for RS-232 serial ommunication. They were developed as the main port for serial connections using RS-232 protocol but most of the applications did not require all the pins.

Hence, DE-9 was developed for RS-232 based serial communication while DB-25 was rarely used as a serial port and often used as a parallel printer port as a replacement of the Centronics Parallel 36 pin connector.

DE-9 or RS-232 or COM Port

DE-9 is the main port for RS-232 serial communication. It is a D-sub connector with E shell and is often miscalled as DB-9. A DE-9 port is also called as a COM port and allows full duplex serial communication between the computer and it’s peripheral.

Some of the applications of DE-9 port are serial interface with mouse, keyboard, modem, uninterruptible power supplies (UPS) and other external RS-232 compatible devices.

The pinout diagram of DE-9 port is shown below.

The use of DB-25 and DE-9 ports for communication is in decline and are replaced by USBs or other ports.

Parallel Port or Centronics 36 Pin Port

Parallel port is an interface between computer and peripheral devices like printers with parallel communication. The Centronics port is a 36 pin port that was developed as an interface for printers and scanners and hence a parallel port is also called as a Centronics port.

Before the wide use of USB ports, parallel ports are very common in printers. The Centronics port was later replaced by DB-25 port with parallel interface.

Audio Ports

Audio ports are used to connect speakers or other audio output devices with the computer. The audio signals can be either analogue or digital and depending on that the port and its corresponding connector differ.

Surround Sound Connectors or 3.5 mm TRS Connector

It is the most commonly found audio port that can be used to connect stereo headphones or surround sound channels. A 6 connector system is included on majority of computers for audio out as well as a microphone connection.

The 6 connectors are color coded as Blue, Lime, Pink, Orange, Black and Grey. These 6 connectors can be used for a surround sound configuration of up to 8 channels.

S/PDIF / TOSLINK

The Sony/Phillips Digital Interface Format (S/PDIF) is an audio interconnect used in home media. It supports digital audio and can be transmitted using a coaxial RCA Audio cable or an optical fiber TOSLINK connector.

Most computers home entertainment systems are equipped with S/PDIF over TOSLINK. TOSLINK (Toshiba Link) is most frequently used digital audio port that can support 7.1 channel surround sound with just one cable. In the following image, the port on the right is an S/PDIF port.

Video Ports

VGA Port

VGA port is found in many computers, projectors, video cards and High Definition TVs. It is a D-sub connector consisting of 15 pins in 3 rows. The connector is called as DE-15.

VGA port is the main interface between computers and older CRT monitors. Even the modern LCD and LED monitors support VGA ports but the picture quality is reduced. VGA carries analogue video signals up to a resolution of 648X480.

With the increase in use of digital video, VGA ports are gradually being replaced by HDMI and Display Ports. Some laptops are equipped with on-board VGA ports in order to connect to external monitors or projectors. The pinout of a VGA port is shown below.

Digital Video Interface (DVI)

DVI is a high speed digital interface between a display controller like a computer and a display device like a monitor. It was developed with an aim of transmitting lossless digital video signals and replace the analogue VGA technology.

There are three types of DVI connectors based on the signals it can carry: DVI-I, DVI-D and DVI-A. DVI-I is a DVI port with integrated analogue and digital signals. DVI-D supports only digital signals and DVI-A supports only analogue signals.

The digital signals can be either single link or dual link where a single link supports a digital signal up to 1920X1080 resolution and a dual link supports a digital signal up to 2560X1600 resolution. The following image compares the structures of DVI-I, DVI-D and DVI-A types along with the pinouts.

Mini-DVI

Mini-DVI port is developed by Apple as an alternative to Mini-VGA port and is physically similar to one. It is smaller than a regular DVI port.

It is a 32 pin port and is capable of transmitting DVI, composite, S-Video and VGA signals with respective adapters. The following image shows a Mini-DVI port and its compatible cable.

Micro-DVI

Micro-DVI port, as the name suggests is physically smaller than Mini-DVI and is capable of transmitting only digital signals.

This port can be connected to external devices with DVI and VGA interfaces and respective adapters are required. In the following image, a Micro-DVI port can be seen adjacent to headphone and USB ports.

Display Port

Display Port is a digital display interface with optional multiple channel audio and other forms of data. Display Port is developed with an aim of replacing VGA and DVI ports as the main interface between a computer and monitor.

The latest version DisplayPort 1.3 can handle a resolution up to 7680 X 4320.

The Display Port has a 20 pin connector, which is a very less number when compared to DVI port and offers better resolution. The pin out diagram of a Display Port is shown below.

RCA Connector

RCA Connector can carry composite video and stereo audio signals over three cables. Composite video transmits analogue video signals and the connector is as yellow colored RCA connector.

The video signals are transmitted over a single channel along with the line and frame synchronization pulses at a maximum resolution of 576i (standard resolution).

The red and white connectors are used for stereo audio signals (red for right channel and white for left channel).

Component Video

Component Video is an interface where the video signals are split into more than two channels and the quality of the video signal is better that Composite video.

Like composite video, component video transmits only video signals and two separate connectors must be used for stereo audio. Component video port can transmit both analogue and digital video signals.

The ports of the commonly found Component video uses 3 connectors and are color coded as Green, Blue and Red.

S-Video

S-Video or Separate Video connector is used for transmitting only video signals. The picture quality is better than that of Composite video but has a lesser resolution than Component video.

The S-Video port is generally black in color and is present on all TVs and most computers. S-Video port looks like a PS/2 port but consists of only 4 pins.

Out of the 4 pins, one pin is used to carry the intensity signals (black and white) and other pin is used to carry color signals. Both these pins have their respective ground pins. The pinout diagram of an S-Video port is shown below.

HDMI

HDMI is an abbreviation of High Definition Media Interface. HDMI is a digital interface to connect High Definition and Ultra High Definition devices like Computer monitors, HDTVs, Blu-Ray players, gaming consoles, High Definition Cameras etc.

HDMI can be used to carry uncompressed video and compressed or uncompressed audio signals. The HDMI port of type A is shown below.

The HDMI connector consists of 19 pins and the latest version of HDMI i.e. HDMI 2.0 can carry digital video signal up to a resolution of 4096×2160 and 32 audio channels. The pinout diagram of an HDMI port is as follows.

USB

Universal Serial Bus (USB) replaced serial ports, parallel ports, PS/2 connectors, game ports and power chargers for portable devices.

USB port can be used to transfer data, act as an interface for peripherals and even act as power supply for devices connected to it. There are three kinds of USB ports: Type A, Type B or mini USB and Micro USB.

USB Type A

USB Type-A port is a 4 pin connector. There are different versions of Type – A USB ports: USB 1.1, USB 2.0 and USB 3.0. USB 3.0 is the common standard and supports a data rate of 400MBps.

USB 3.1 is also released and supports a data rate up to 10Gbps. The USB 2.0 is Black color coded and USB 3.0 is Blue. The following image shows USB 2.0 and USB 3.0 ports.

The pinout diagram of USB Type – A port is shown below. The pinout is common to all standards of Type – A.

USB Type C

USB Type – C is the latest specification of the USB and is a reversible connector. USB Type – C is supposed to replace Types A and B and is considered future proof.

The port of USB Type – C consists of 24 pins. The pinout diagram of USB Type – C is shown below. USB Type – C can handle a current of 3A.

This feature of handling high current is used in the latest Fast Charging Technology where a Smart Phone’s battery will reach its full charge is very less time.

RJ-45

Ethernet is a networking technology that is used to connect your computer to Internet and communicate with other computers or networking devices.

The interface that is used for computer networking and telecommunications is known as Registered Jack (RJ) and RJ – 45 port in particular is used for Ethernet over cable. RJ-45 connector is an 8 pin – 8 contact (8P – 8C) type modular connector.

The latest Ethernet technology is called Gigabit Ethernet and supports a data transfer rate of over 10Gigabits per second. The Ethernet or a LAN port with 8P – 8C type connector along with the male RJ-45 cable is shown below.

The un-keyed 8P – 8C modular connector is generally referred to the Ethernet RJ-45. Often, RJ-45 ports are equipped with two LEDs for indicating transmission and packet detection.

As mentioned earlier, an Ethernet RJ-45 port has 8 pins and the following picture depicts the pinout of one.

RJ-11

RJ-11 is another type of Registered Jack that is used as an interface for telephone, modem or ADSL connections. Even though computers are almost never equipped with an RJ-11 port, they are the main interface in all telecommunication networks.

RJ-45 and RJ11 ports look alike but RJ-11 is a smaller port and uses a 6 point – 4 contact (6P – 4C) connector even though a 6 point – 2 contact (6P – 2C) is sufficient. The following is a picture of an RJ-11 port and its compatible connector.

The following image can be used to compare RJ-45 and RJ-11 ports.

e-SATA

e-SATA is an external Serial AT Attachment connector that is used as an interface for connecting external mass storage devices. Modern e-SATA connector are called e-SATAp and stands for Power e-SATA ports.

They are hybrid ports capable of supporting both e-SATA and USB. Neither the SATA organization nor the USB organization has officially approved the e-SATAp port and must be used at user’s risk.

The above image is of an e-SATAp port. It shows that both e-SATA and USB devices can be connected.

Create Resume in Ms Word.....

 

What is a Résumé?

A résumé, often referred to as a CV (curriculum vitae), is a summary of a person’s background and experience, including work experience, education, and even volunteer work, and its most common use is to send to potential employers when searching for a new career opportunity. In fact, though taking on a much different form than that of what you’d expect a résumé to look like today, Leonardo Da Vinci even did this himself, and he is often given credit as the first person to create a resume.

Of course, the résumé has undergone quite the transformation since Da Vinci’s 1482 version, drastically so during the age of word processors and digital typesetting in the 1970’s—40 years after résumés became an institution. Fast-forward to today and not only do you have your standard .doc or .pdf résumé, but you’ll also see people uploading video résumés on YouTube and using social media platforms like LinkedIn to sell themselves to companies.

We should be thankful for these developments because now we can skip the quill and ink and jump straight into Microsoft Word.

Using a Microsoft Word Résumé Template

Microsoft Word offers a bunch of résumé templates. Some are beautiful; some are not. We’ll let you decide which style fits you best, but here’s where you can find them.

Go ahead and open Word. As soon as you do, you’ll be greeted with several different templates to choose from, ranging from a simple blank document, cover letters, résumés, or even seasonal event flyers. Click the “Resumes and Cover Letters” link under the search box to see only those types of templates.

Now, you’ll see all the different resume styles Word has to offer. There are a lot of different styles and color schemes to choose one, so pick what feels right. If you scroll down the list a bit, you’ll also see some plainer resume templates designed for different purposes—like an entry-level, chronological, or extended CV style.

Some of the templates are already built into Word; others are a quick, free download from Office.com (and you won’t even have to leave Word to grab them). When you click to create a resume, Word will let you know the download size (if it needs to download the template). Click the “Create” button and a few seconds later, you’ll be in your document and ready to edit.

 

 

That’s all there is to it! But what if you didn’t find a résumé you liked? Luckily, Word has a few formatting tools to help you craft the perfect résumé.

Crafting a Custom Résumé in Microsoft Word

Before we start, it’s important to know that each résumé should reflect a person’s personal experience and education. Since everyone’s experience is different, it’s no surprise that their résumés will be too.

That being said, there are some general aesthetic guidelines for making a résumé that we highly recommend you follow.

Go ahead and open up a clean, blank document in Word.

The first thing we’ll want to do is set our margins. Go to the “Layout” tab and click the “Margins” buttons.

The drop-down menu displays several different margin options from which to choose. If you can’t find the one you’re looking for, you can click “Custom Margins” at the bottom and enter your specifications. Let’s go ahead and do that.

According to the experts, the best margin size is 1” for the top and bottom and 0.63” for the sides. This may seem like an oddly specific number, but the objective is to get as much (relevant) information about yourself as possible on a page without overwhelming the reader. With the above credentials, we leave enough white space on the page for the reader to not feel suffocated.

Click “OK” once you’ve entered the margin sizes you want.

Deciding What Information To Include

Now that our margins are set, it’s time to start inputting information.

The information you put mainly depends on what you’re trying to accomplish and where you are in your professional career. If you have over two years of working experience, then detailing that information is much more valuable than which high school you graduated from or which clubs you were a part of in college. Like a cover letter, your résumé should uniquely cater to the recipient. Dress to impress.

So, which information should you put? We’ll give you the overview, and you can decide which areas you should detail.

• Contact Information
• Professional Experience (It’s also ok to include any volunteer work at the bottom of this section)
• Education
• Additional Skills

For all of these, tailor the information to the job. You don’t need to fit irrelevant work experience in there unless not including it would create a gap in your work experience. But if you’re applying for a job as an accountant, nobody cares that you delivered pizzas 12 years ago. And you do list out any additional skills, make sure they’re relevant to the position for which you’re applying. Your high school friend might be impressed by how high you can kick, but your future employer—not so much.

Another thing to remember is that you should always list out your experience in reverse chronological order. That is, list out your most recent experience first, and go back from there.

Organizing That Information

There’re several ways to do this, but arguably the most effective way is by creating headings and then inserting a table for the content of each section. By doing so, you’re not only able to move content around in groups instead of individually, which can be a headache in itself, but you’re also able to give your résumé a unique touch by adding table designs. In the image below, for example, we’ve added a dashed border to the left side of the table to create a nice little visual element to tie the different experience elements together.

First things first, let’s go ahead and find a heading that we like. In the “Styles” section of the “Home” tab, you’ll find several default styles. If you can’t find one you like, then Word has a feature that lets you create your own. First, click the “More” arrow on the right-hand side of the different built-in styles.

You’ll see a menu with three different options. Go ahead and click “Create a Style.”

The “Create New Style from Formatting” window will appear. The only thing you can do here is to name the style, so click “Modify.”

Now you should see a window with many formatting options. For fonts, there’s no best option. Just make sure you use something that’s clean and readable. “Georgia” is a great example. A 14 pt font size is fine for headings, but make sure it’s bold so that each section is easier to find for the reader.

The “Add to the Styles gallery” option will automatically be selected. It’s good to leave this option selected so you’ll have easy access to your heading for the other sections of your résumé. If you plan to use this heading again in future documents, you can go ahead and deselect “Only in this document,” but since we only plan to use it for our résumé, we’ll keep that option selected.

Click “OK.”

Go ahead and type in your first heading and apply the new style to it. In this example, we’ll use “Experience” first.

Now, let’s use a table under our first heading so that we can keep all our content lined up correctly. Place your insertion point on the line under your new heading, switch to the “Insert” tab, and click the “Table” button.

You’ll see a 10×8 grid on the drop-down menu. You can create the table size by moving your mouse over the grid and clicking when it’s the size you want. For your résumé, you’ll need one column and enough rows to contain the separate pieces of information you have to list. For example, if you have three prior jobs to list in the Experience section, you’ll want a table that’s 1×3.

And here’s what it looks like after we’ve inserted the table into the document.

We’ll remove the border lines later. First, go ahead and put in your information. You’ll want the “Job Title, Company” text to be 1 or 2 pts larger than the rest of the text but be sure to keep it smaller than the heading of the section. If you want your job title to stand out, you can change the color or make it italic, but try to keep it simple.

Once that’s ready, let’s go ahead change the borders of our table. Select the table by placing your insertion point anywhere inside it. Switch to the “Design” tab in the “Table Tools” section of the Ribbon, and then click the “Borders” button.

If you want to keep it simple and remove all the lines of your table, select “No Border.” In this example, we’re going to give our table a little flavor, so we’ll select “Borders and Shading.”

Because we only want to customize the left border of our table, we will select “Custom” under the “Setting” section. This lets us use the “Preview” section to deselect the sides on which we don’t want borders. Click the boxes surrounding the preview to turn off all the borders except for the left one.

In the “Style” list, you can select the border design, color, and width you want. Click “OK” when you’re ready.

Now we should have an experience section on our résumé that’s starting to shape up. A little playing with colors and maybe spacing the table rows a bit, and you should be ready to go.

 

Types Of Printers

“A printer is an external output device that takes data from a computer and generates output in the form of graphics / text on a paper”.

There are two types of printers.

Impact Printers

An impact printer makes contact with the paper. It usually forms the print image by pressing an inked ribbon against the paper using a hammer or pins. Following are some examples of impact printers.

 Dot-Matrix Printers

The dot-matrix printer uses print heads containing from 9 to 24 pins. These pins produce patterns of dots on the paper to form the individual characters. The 24 pin dot-matrix printer produces more dots that a 9 pin dot-matrix printer, which results in much better quality and clearer characters. The general rule is: the more pins, the clearer the letters on the paper. The pins strike the ribbon individually as the print mechanism moves across the entire print line in both directions, i-e, from left to right, then right to left, and so on. The user can produce a color output with a dot-matrix printer (the user will change the black ribbon with a ribbon that has color stripes). Dot-matrix printers are inexpensive and typically print at speeds of 100-600 characters per second.

Daisy-Wheel Printers

In order to get the quality of type found on typewriters, a daisy-wheel impact printer can be used. It is called daisy-wheel printer because the print mechanism looks like a daisy; at the end of each “Petal” is a fully formed character which produces solid-line print. A hammer strikes a “petal” containing a character against the ribbon, and the character prints on the paper. Its speed is slow typically 25-55 characters per second.

Line Printers

In business where enormous amount of material are printed, the character-at-a-time printers are too slow; therefore, these users need line-at-a-time printers. Line printers, or line-at-a-time printers, use special mechanism that can print a whole line at once; they can typically print the range of 1,200 to 6,000 lines per minute. Drum, chain, and band printers are line-at-a-time printers.

Drum Printer

A drum printer consists of a solid, cylindrical drum that has raised characters in bands on its surface. The number of print positions across the drum equals the number available on the page. This number typically ranges from 80-132 print positions. The drum rotates at a rapid speed. For each possible print position there is a print hammer located behind the paper. These hammers strike the paper, along the ink ribbon, against the proper character on the drum as it passes. One revolution of the drum is required to print each line. This means that all characters on the line are not printed at exactly the same time, but the time required to print the entire line is fast enough to call them line printers. Typical speeds of drum printers are in the range of 300 to 2000 lines per minute.

Chain Printers

A chain printer uses a chain of print characters wrapped around two pulleys. Like the drum printer, there is one hammer for each print position. Circuitry inside the printer detects when the correct character appears at the desired print location on the page. The hammer then strikes the page, pressing the paper against a ribbon and the character located at the desired print position. An impression of the character is left on the page. The chain keeps rotating until all the required print positions on the line have filled. Then the page moves up to print the next line. Speeds of chain printers range from 400 to 2500 characters per minute.

Band Printers

A band printer operates similar to chain printer except it uses a band instead of a chain and has fewer hammers. Band printer has a steel band divided into five sections of 48 characters each. The hammers on a band printer are mounted on a cartridge that moves across the paper to the appropriate positions. Characters are rotated into place and struck by the hammers. Font styles can easily be changed by replacing a band or chain.

Non-Impact Printers

Non-impact printers do not use a striking device to produce characters on the paper; and because these printers do not hammer against the paper they are much quieter. Following are some non-impacted printers.

Ink-Jet Printers

Ink-jet printers work in the same fashion as dot-matrix printers in the form images or characters with little dots. However, the dots are formed by tiny droplets of ink. Ink-jet printers form characters on paper by spraying ink from tiny nozzles through an electrical field that arranges the charged ink particles into characters at the rate of approximately 250 characters per second. The ink is absorbed into the paper and dries instantly. Various colors of ink can also be used.

One or more nozzles in the print head emit a steady stream of ink drops. Droplets of ink are electrically charged after leaving the nozzle. The droplets are then guided to the paper by electrically charged deflecting plates [one plate has positive charge (upper plate) and the other has negative charge (lover plate)]. A nozzle for black ink may be all that’s needed to print text, but full-color printing is also possible with the addition of needed to print text, but full-color printing is also possible with the addition three extra nozzles for the cyan, magenta, and yellow primary colors. If a droplet isn’t needed for the character or image being formed, it is recycled back to its input nozzle.

Several manufacturers produce color ink-jet printer. Some of these printers come with all their color inks in a cartridge; if you want to replace on color, you must replace all the colors. Other color ink-jet printers allow you to replace ink individually. These printers are a better choice if user uses one color more than other colors. These printers produce less noise and print in better quality with greater speed.

Laser Printers

A laser printer works like a photocopy machine. Laser printers produce images on paper by directing a laser beam at a mirror which bounces the beam onto a drum. The drum has a special coating on it to which toner (an ink powder) sticks. Using patterns of small dots, a laser beam conveys information from the computer to a positively charged drum to become neutralized. From all those areas of drum which become neutralized, the toner detaches. As the paper rolls by the drum, the toner is transferred to the paper printing the letters or other graphics on the paper. A hot roller bonds the toner to the paper.

Laser printers use buffers that store an entire page at a time. When a whole page is loaded, it will be printed. The speed of laser printers is high and they print quietly without producing much noise. Many home-use laser printers can print eight pages per minute, but faster and print approximately 21,000 lines per minute, or 437 pages per minute if each page contains 48 lines. When high speed laser printers were introduced they were expensive. Developments in the last few years have provided relatively low-cost laser printers for use in small businesses.

Advantages Of Laser Printer

• The main advantage of Laser printer is its speed & efficiency at which it prints high-quality quality graphics & text.
• Laser printers produce high-quality output as compared to other printers.
• Laser printers are quite and does not produce disturbing sounds.
• They are also capable to produce color prints.

 Disadvantages Of Laser Printer

• The main disadvantage of Laser printer is its cost, they are relatively costly as compared to other printers.
• The maintenance, repair & servicing charges are also high of these printers.
• Laser printers emit small amount of ozone and are hazardous to health and the atmosphere.