What are computer ports for? Purpose and types of input/output ports on a computer

Greetings, friends. We continue to study the system unit. Today I’ll talk about computer ports. What it is? With the rapid development of Internet technologies, the concept of “port” or “socket” is familiar to many. This is another branch, and we will not talk about it today. The topic of this article contains information about purely “hard”, “real” connectors (or ports), which are designed to connect various devices to the system unit.

Hardware is also improving, and with each generation we discover new types of connectors (or ports) on purchased system units. Various so-called peripheral devices are connected to them. System unit + monitor = computer. Everything that is connected to them (printers, scanners, programmers, video cards, monitors, and so on) is a peripheral.

There are many ports on a computer. They are located on the motherboard of the system unit and are connectors (most of them are on the back). Some of the connectors are also displayed on the front panel and they are also connected to the motherboard.

You can also install additional devices on it through special expansion slots. Such devices include discrete video cards, network cards, Wi-Fi adapters, USB hubs, card readers, electronic locks, video cards and much more.

The presence of expansion slots allows you to independently assemble a computer like a construction set, based on your preferences, without spending an extra day. Because the developers have long standardized the equipment they produce. If necessary, you can update it. This is the main reason that IBM-PC compatible computers (as such a platform is called) once ousted the Apple Macintosh from the market.

Their system units were initially non-separable, and the equipment was not replaceable. It is impossible to upgrade such a device, and the maintainability of such a device is reduced.

A short list of computer ports

You need to be able to distinguish connectors from one another visually. The manufacturer does not always indicate their names. Since the connectors are grouped on the rear panel of the system unit, we’ll start there. All ports have an English name, nothing can be done about it. They can be briefly divided:

1. Serial ports;
2. Parallel port;
3. Ports for computer and mouse;
4. USB ports;
5. SCSI ports;
6. Video ports;
7. Network cable connectors;
8. Audio connectors;
9. Card readers;

Some of these varieties have already sunk into oblivion and can no longer be found on modern motherboards. Other varieties, on the contrary, expand their functionality and there are motherboards for gourmets - lovers of good quality audio or video.

Such boards can also support audio or video formats from third-party manufacturers (Sony, Philips), and then you can find a corresponding connector on such a computer. Audio and video ports today boast a particular variety.

Computer ports for connecting peripheral devices

Serial port- today it is already a morally outdated thing. But for specialists who repair electronic devices, they are valuable. Initially, this port was used to connect a modem. Typical data transfer rates range from 110 to 115,200 bits per second. There were usually two of them with connectors DB 9 type "dad":

The speed is quite enough for the programmer to flash a microcontroller or mobile phone. Or to exchange data with an uninterruptible power supply. These ports are called COM1 And COM2.

Parallel port- is familiar to many, because it was mainly intended for connecting a printer. Also an almost extinct species. It was also used to connect hardware security keys.

The connector is used for connection DB25 like "mom". The data transfer speed is low - but quite enough for a programmer or an old laser printer. Most old computers always had two serial ports and one parallel port.

Keyboard and mouse ports familiar to all users. In modern computers they are purple and green. The plugs on the mouse and keyboard are the same color. It's difficult to confuse. The connectors are six-pin (mini-Din) female type. They were invented in Germany and it became the standard. Another name for IBM/PC2

since they were first used on the already mentioned IBM PC platform. If the connectors are mixed up when connecting, the devices will not work. A definite plus is that USB ports save money. Minus - you must restart the computer if it is connected incorrectly. By the way, it is also an endangered species. On many modern computers, this port is left only one - and it is also painted purple-green. You can connect only one device or mouse or keyboard to it.

USB ports. Universal Serial Bus, ( Universal Serial Bus). Since 1998, it has been displacing other ports; Even on car radios and video cameras today you will find this connector. The first generations had a data transfer speed of about 12 MB/sec. - mind-blowing for those times. Today we use USB 3, which has a speed of 5 Gbps

These ports have not changed in appearance. The computer has type A connectors. The connector on any connected device is usually called “B”. It has four contacts, two for current, two for data transmission. Accordingly, there are twice as many pins on USB 3.0 ports.

SCSI ports(Small Computer Systems Interface) . Quite a specific and rare thing for us; I think that even abroad you will no longer find it among the average user. I believe that devices with such interfaces were made to order - for corporate use. This is a network interface for data exchange at speeds up to 160 Mbit/s.

I once came across a laptop brought from America, manufactured in 1999, from Dell. It had one of those multi-pin ports. It was located in such a way that it could only be used by placing the laptop on the table. The connector itself is closed with curtains on springs. Consequently, somewhere in America there were tables in which this connector was built in... You bring it, put it on the table, and it is connected to the corporate network.

The interface varieties are already familiar to us DB-25, as well as 50-High-Density, 68-pin -High-Density, 80-pin SCA, Centronics. It was also possible to connect hard drives to this interface. A special board, the host adapter, is responsible for the connection.

Video ports. They also cannot be confused with others. The standard video port is a 15-pin VGA blue D-type female connector. Used to connect a monitor. This is an old standard, adopted in 1987. Not all motherboards have it. If you don’t have it “on board”, then it can be found at the bottom of the system unit. A video card is installed in the expansion slot:

If you decide to install a video card in addition to the one you already have (“on board”), then the latter will no longer work. This is fine. The monitor will only work when connected to an installed one.

On modern video cards, the VGA port has become difficult to find; they are being replaced by another type - DVI. On a transition type motherboard it looks something like this:

Very often there are cases when a VGA video card fails. After purchasing a new one, it turns out that it only has DVI ports. In this case, you need to purchase an adapter and install it on the DVI connector:

Pay attention to the type of adapter. The fact is that the DVI connectors are different - new expensive video cards have DVI-D or DVI-I ports. The adapters are not interchangeable, check this point with the seller.

In this case, you will not need to buy a new monitor. New monitors also come with two types of connectors - VGA and DVI.

HDMI port. Where would we be without him in the 21st century? The multimedia interface is designed to transmit high-definition video and audio with copy protection. At the same time, it replaces both the above video and some audio ports (SCART, VGA, YPbPr, RCA, S-Video.). This interface will probably replace everything else over time. It can be found on any digital technology - from a camera to a computer (or laptop).

The size is comparable to a USB port, and the data transfer speed is enormous compared to those listed above - up to 48 Gbps. Data transmission is carried out via a cable with good interference protection. The cable can be connected to a laptop and to a TV and watch videos. The cable length should not exceed 10 meters, otherwise a signal amplifier/repeater is needed.

About audio connectors I won't go into detail. Everything looks about the same as on a home DVD player, if we are talking about something special. An example of this is the SPDiF connector, which could be installed on an expansion slot:

Audio standard from SONY and PHILIPS, this card is connected to the motherboard using a connector to the corresponding connector. Standard jacks for connecting a microphone, speakers, and headphones look like this:

If you want HD audio, you may have to connect the appropriate adapter here. Read the documentation for your motherboard:

Network ports. There is no way we can do without them these days. We receive the Internet through a network interface via cable or radio. Motherboards have a standard built-in connector RJ 45 to connect the internet cable:

On old computers, the speed standard was 100 Mbit/s; modern network cards provide 1000 Mbit/s. If one network card is not enough for you, you can buy an additional one and insert it into the expansion slot:

This card is suitable for a PCI slot. There are smaller options for PCI-express:

Check the data transfer speed of a particular card when purchasing. For fans of wireless networks, there is also a wide selection of Wi-Fi adapters:

They can also be connected to PCI or PCI - express expansion slots. However, if you don’t want to tinker with the system unit, you can also buy a USB version of this card:

You insert it into the port and enter the WIFI password. And you have another peripheral device connected. Many home printer models also have a WIi-Fi adapter, and with this setup you can print wirelessly. Fortunately, today there is a wide choice of network cards and printers.

How to disable USB ports when turning off the computer?

Finally, I’ll tell you how to solve one problem. I have a headset with a microphone for recording video and chatting on Skype. The Chinese have fallen in love with shoving LEDs wherever they need them for beauty. When the computer turns off, the backlight still remains on, since it is powered through the USB port.

The keyboard also glows, which is not entirely convenient at night, although not bad (if you type in the dark). To turn off power to the ports permanently, try typing the keyboard shortcut Win+R and in the “Run” line paste the command powercfg /h off.

After which you need to turn off the computer. The symptoms will likely go away. This command disables sleep mode and the computer shuts down completely. You can look at the power settings in the “Power Plan” in the control panel. But, there are board models where this setting is disabled through the BIOS. But on the most advanced ones this function is not disabled or is hidden very deeply. This is supposed to be convenient for charging gadgets at night.

In difficult cases, the motherboard documentation can help. Find the desired jumper (jumper) and manually turn off the power. But it's too difficult. And the easiest way is to buy a USB hub with switches and connect the necessary peripherals to it. And don't suffer. Bye, see you again!

A modern personal computer would never have gained such enormous popularity if it only performed computing functions. The current PC is a multifunctional device, with the help of which the user can not only carry out any calculations, but also perform a lot of different things: print text, control external devices, communicate with other users using computer networks, etc. All this enormous functionality is achieved with the help of additional devices - peripherals, which are connected to a personal computer through special connectors called ports.

Personal computer ports

Port- an electronic device running directly on the PC motherboard or on additional boards installed in a personal computer. The ports have a unique connector for connecting external devices – peripherals. They are intended for data exchange between a PC and external devices (printers, modems, digital cameras, etc.). Quite often, in the literature you can find another name for ports - interfaces.

All ports can be divided into two groups:

• External- for connecting external devices (printers, scanners, plotters, video devices, modems, etc.);
• Domestic- for connecting internal devices (hard drives, expansion cards).

External ports of a personal computer

1. PS/2- port for connecting a keyboard;
2. PS/2- port for connecting a mouse;
3. Ethernet- port for connecting a local network and network devices (routers, modems, etc.);
4. USB- port for connecting external peripheral devices (printers, scanners, smartphones, etc.);
5. LPT- parallel port. Serves to connect now outdated models of printers, scanners and plotters;
6. COM- RS232 serial port. Used to connect devices such as dial-up modems and old printers. Now outdated, practically not used;
7. MIDI- a port for connecting game consoles, midi keyboards, musical instruments with the same interface. Recently, it has been practically replaced by the USB port;
8. Audio In- analog input for linear output of audio devices (tape recorders, players, etc.);
9. Audio Out- analog audio signal output (headphones, speakers, etc.);
10. Microphone- microphone output for connecting a microphone;
11. SVGA- a port for connecting video display devices: monitors, modern LED, LCD and plasma panels (this type of connector is obsolete);
12. VID Out- the port is used to output and input low-frequency video signals;
13. DVI- a port for connecting video display devices, more modern than SVGA.

Serial port (COM port)

One of the oldest ports installed in PCs for more than 20 years. You can find it quite often in literature classic name – RS232. Data exchange using it occurs in serial mode, that is, the transmission and reception lines are one-bit. Thus, information that is transmitted from a computer to a device or vice versa is divided into bits that follow each other sequentially.

The data transfer speed provided by this port is not high, and has a standardized range: 50, 100, 150, 300, 1200, 2400, 4800, 9600, 14400, 38400, 57600, 115200 Kbps.

A serial port was used to connect such “slow” devices to a PC as the first printers and plotters, dial-up modems, mice, and even to connect computers with each other. No matter how slow its speed, in order to connect the devices to each other, only three wires were required - the data exchange protocol was so simple. It is clear that for full operation a larger number of conductors in the cord was required.

Today, the serial port is practically no longer used and is completely supplanted by its younger, but also faster “brother” - USB port. It should be noted, however, that some manufacturers still equip their motherboards with a COM port. However, the name itself - “serial port” is still used by software developers. For example, Bluetooth devices and cell phone ports are often presented as a “serial port.” This may be a little confusing, but this is done because they also transfer data serially, but at a higher speed.

If for some reason you may need a COM port, but your PC does not have one, then for this purpose you can use an adapter that connects to a modern USB port, which is available on all modern PCs, and on the other hand, such an adapter has serial port connector. There is, however, one limitation: if the software accessed directly the hardware of a real COM port, then it will not work with such an adapter. In this case, you need to purchase a special board that is installed inside your PC.

Structurally, the PC serial port has a male connector (with protruding pins):

Today, the 25-pin serial port connector has practically fallen out of use and has not been installed on a PC for several years. If the manufacturer provides the motherboard with a COM port, then it is a 9-pin DB9 connector.

It is an interface for connecting devices such as printers, scanners and plotters.

Allows you to simultaneously transmit 8 bits of data, albeit in one direction - from the computer to the periphery. In addition to this, it has 4 control bits (as with data bits, control bits are transferred from the PC to the external device), and 4 status bits (these bits can be “read” by the computer from the device).

In recent years, the LPT port has been improved, and it has become two-way, that is, it has become possible to transmit data bits through it in both directions. Today it is outdated and practically not used, although motherboard manufacturers still include it in its composition.

Enthusiasts and radio amateurs often use this port to control any non-standard devices (crafts, etc.).

USB interface

USB– this is an abbreviation of the full name of the port – universal serial bus (“universal serial bus”).

It is one of the most widely used ports on a personal computer today. And this is no coincidence - its technical characteristics and ease of use are truly impressive.

The data exchange speed for the USB 2.0 interface can reach 480 Mbit/s, and for the USB3.0 interface – up to 5 Gbit/s (!).

Moreover, all versions of this interface are compatible with each other. That is, a device using interface 2.0 can be connected to a USB3.0 port (in this case, the port will automatically reduce the speed to the desired value). Accordingly, a device using a USB 3.0 port can be connected to a USB 2.0 port. The only condition is that if normal operation requires a speed higher than the maximum speed of USB 2.0, then the normal functioning of the peripheral device will not be possible in this case.

In addition, the popularity of this port is also due to the fact that the developers included one very useful feature in it - this port can serve as a power source, for an external device connected to it. In this case, no additional unit is required to connect to the electrical network, which is very convenient.

For the USB 2.0 port version, the maximum current consumption can reach 0.5A, and for the USB3.0 version – 0.9A. It is not recommended to exceed the specified values, as this will lead to failure of the interface.

Developers of modern digital devices are constantly striving for minimization. Therefore, structurally, this port can have, in addition to a standard connector, also a mini-version for miniature devices - mini-USB. It has no fundamental differences from a standard USB port other than the design of the mini-USB connector itself.

Almost all modern devices have a USB port for connecting to a PC. Ease of installation - the connected device is recognized by the operating system almost immediately after connection, making it possible to use such a port without special “computer” knowledge. Printers, scanners, digital cameras, smartphones and tablets, external drives are just a small list of peripheral equipment that currently uses this interface. A simple principle - “plug and play” made this port truly a bestseller among all currently available personal computer interfaces.

Fire-Wire port (Other names - IEEE1394, i-Link)

This type of interface appeared relatively recently - since 1995. It is a high-speed serial bus. Data transfer rates can reach up to 400 Mbit/s in the IEEE 1394 and IEEE 1394a standard, 800 Mbit/s and 1600 Mbit/s in the IEEE1394b standard.

Initially, this interface was designed as a port for connecting internal drives (SATA type), but the licensing policy of Apple, one of the developers of this standard, required payment for each controller chip. Therefore, today only a small number of digital devices (some models of cameras and video cameras) are equipped with this type of interface. This type of port never became widespread.

The importance of this interface can hardly be overestimated; as a rule, it is what is used to connect a personal computer to a local network or to access the Internet in most cases. Almost all modern PCs, laptops and netbooks are equipped with an Ethernet port built into the motherboard. This is easy to verify if you examine the external connectors.

To connect external devices, a special one is used, which has identical connectors at both ends. connectors – RJ-45, containing eight contacts.

The cable is symmetrical, therefore, the order in which the devices are connected does not matter - any device of your choice can be connected to any of the identical cable connectors - a PC, router, modem, etc. It is marked with the abbreviation - UTP, common name is “twisted pair”. In most cases, for both home and office use, a cable of the fifth category, UTP-5 or UTP-5E, is used.

The speed of data transmitted over an Ethernet connection depends on the technical capabilities of the port and is 10 Mbit/s, 100 Mbit/s and 1000 Mbit/s. It should be understood that this throughput is theoretical, and that in real networks it is somewhat lower due to the peculiarities of the Ethernet data transfer protocol.

Also, you should keep in mind that not all manufacturers install high-speed chips in their Ethernet controllers, since they are very expensive. This leads to the fact that in practice, the actual data transfer speed is much lower than that indicated on the packaging or in the specification. As a rule, almost all Ethernet cards are compatible with each other and from top to bottom. That is, newer models that have the ability to connect at speeds of 1000 Mbit/s (1 Gbit/s) will work without problems with older models at speeds of 10 and 100 Mbit/s.

To visually monitor the integrity of the connection, the Ethernet port has Link and Act indicators. Link indicator - lights green when the physical connection is correct and working, i.e. the cable between the devices is connected, it is intact, the ports are working. The second Act indicator (“activity”) is usually orange and flashes while transmitting or receiving data.

Internal ports of a personal computer

As mentioned above, internal ports are designed for connecting peripherals such as hard drives, CDs and DVD-ROMs, card readers, additional COM and USB ports, etc. Internal ports are located either on the motherboard, or on additional expansion cards installed in the system bus.

A now outdated interface for connecting older models of hard drives (“hard drives”, HDD). After the creation of the SATA interface, it was called the PATA interface, or ATA for short. PATA – ParallelAdvanced Technology Attachment. This parallel data transfer interface for connecting drives was developed in mid-1986 by the now famous company WesternDigital.

Depending on the manufacturer, the motherboard may contain from one to four IDE channels. Modern manufacturers, as a rule, leave only one IDE port for compatibility, and recently it has also been excluded from the motherboard, having been completely replaced by the modern SATA interface.

The data transfer speed in the latest version of the EnhancedIDE interface can reach 150 Mbit/s. Devices are connected using an IDE cable having 40 or 80 cores for the old or new interface type, respectively.

Typically, you can connect up to two devices simultaneously to one IDE port using a single cable. In this case, using jumpers on the drives that determine the “seniority” of devices operating in pairs, the operating mode is selected - on one device - "master", and for the other "subordinate" (slave).

You can connect either the same type of device, for example, two hard drives or two DVD-ROMs, or different devices in any combination - DVD-ROM and HDD or CD-ROM and DVD-ROM. The connector for connection does not matter, you should just pay attention that the two connectors for connecting peripherals are shifted for convenience to one of the ends of the cable.

You should also keep in mind that by connecting a “fast” device designed for an 80-wire cable using an old 40-wire cable, you will greatly reduce the exchange speed. In addition, if one of the devices in the pair has an old (slow) ATA interface, then the data transfer speed in this case will be determined precisely by the speed of this device.

If there are two IDE ports and two drives inside the PC, to increase the data exchange speed, you must connect each drive to a separate IDE port.

This interface is a development of its predecessor, the IDE interface, with the only difference that, unlike its “older friend,” it is not a parallel, but a serial interface. SATA – SerialATA.

Structurally, it has only seven conductors for its operation and a much smaller area of ​​​​both the connector itself and the connecting cable.

The data transfer speed of this interface is significantly higher than the outdated IDE and, depending on the SATA version, is:

1. SATARev. 1.0 – up to 1.5 Gbit/s;
2. SATARev. 2.0 – up to 3 Gbit/s;
3. SATARev. 3.0 – up to 6 Gbit/sec.

Just like the IDE interface, the cord for connecting devices is “universal” - the connectors are the same on both sides, but unlike its “brother”, now you can connect only one device to one SATA port using one SATA cable.

But there is hardly any need to be upset about this. Manufacturers made sure that the number of ports was sufficient for a wide variety of applications, installing up to 8 SATA ports on one motherboard. The third revision SATA port connector is usually bright red.

Additional ports

Most motherboards are equipped by manufacturers with an additional number of USB ports, and sometimes with another, additional COM port.

This is done for the convenience of the user. Most modern desktop PC cases have USB connectors installed on the front panel for convenient connection of external drives. In this case, you do not need to reach to the back wall of the system unit and “get into” the USB connector, which is located on the rear panel.

This connector is on the front panel and connects to an additional USB port installed on the motherboard. Among other things, the USB interfaces located on the rear panel may simply not be enough, due to the large number of peripheral devices, in this case you can purchase additional bracket with USB connectors and connect them to additional ports.

All of the above also applies to other ports installed on the motherboard. For example, a COM or FireWireIEEE1394 serial port may simply not be displayed on the back panel of a personal computer, but it is still present on the motherboard. In this case, it is enough to buy the appropriate cable and take it out.

It would be technically incorrect to call these connectors ports, although the method of connecting additional cards to them is still somewhat similar to other conventional ports. The principle is the same - plug it in and turn it on. In most cases, the system will find the device itself and request (or install automatically) drivers for it.

Such buses are used to install, for example, an external graphics card, a sound card, an internal modem, a video input card, and other additional expansion cards that allow the PC to expand its functions and capabilities.

PCI and PCIe buses are incompatible with each other, so before purchasing an expansion card, you need to find out which system buses are installed on the motherboard of your PC.

PCIex 1 and PCIex 16 are modern implementations of the older PCI bus, developed in 1991. But unlike its predecessor, it is a serial bus, and in addition, all PCIe buses are connected in a star topology, while the old PCI bus was connected in parallel to each other. In addition, the new tire has the following advantages:

1. Possibility of hot replacement of boards;
2. The bandwidth has guaranteed parameters;
3. Control of data integrity during reception and transmission;
4. Controlled energy consumption.

PCI Express buses differ in the number of conductors connected to the slot, through which data is exchanged with the installed device (PCIex 1, PCIex2, PCIex 4, PCIex 8, PCIex 16, PCIex 32). The maximum data transfer speed can reach 16 Gbit/s.

In this article I will try to list the most common types of interfaces and ports that may be present on a computer, laptop, smartphone, or other similar device. Each type of port has its own structure and purpose, unique to it. It is clear that the presence of various ports in the device allows you to connect and use many different equipment, expanding the standard capabilities of a computer, laptop or smartphone.

The most common and common interface in computer equipment is . The USB port is designed for connecting various additional equipment to transfer digital data at high speed. Modern USB ports also allow you to transfer electricity, for example, by connecting a smartphone to a computer via USB, you can transfer data in both directions and at the same time charge the device’s battery.

There are several USB standards that differ in information transfer speed, currently this is . There are also several types of interfaces that differ in connector design. There are 4 types of USB ports, which are shown in the figure above.

In almost every laptop you can find the so-called. This connector is designed for data transfer, just like a USB port. The main advantage of this connector is its high data exchange speed, comparable to the USB 3.0 standard, as well as the ability to connect devices in a daisy chain with the ability to transfer data.

In a computer, laptop or all-in-one computer, also called an Ethernet connector is found almost everywhere. This type of interface is designed to connect an Ethernet cable used to create a wired Internet connection.

Firewire port, also called IEEE 1394. Outwardly, it looks a little like USB, but only a little. This interface is quite rare; the Firewire port is typical for Apple devices. This interface is designed for data transfer, similar to the first two ports. Most often it is used to connect video cameras.

Audio jack

This type of interface is found in almost all modern computer devices; it is designed to connect headphones and a microphone. It is typical for almost all devices to have exactly two connectors, one 3.5 mm jack for headphones and a similar one for a microphone. Less often you can find one combo interface for connecting both a microphone and headphones.

This interface is called, it is intended for connecting a monitor. It is found in computers, laptops and less often in other devices.

HDMI port

This interface is called HDMI. Lately it has become more and more popular and has several standards and versions. The HDMI port is designed to transmit high-quality video content. Used in almost all modern computer devices.

Kensington Lock

This hole is typical for laptops, it is called Kensington and is designed to secure the laptop to various surfaces through an appropriate cord, to protect against theft. Often such an interface is used at computer equipment exhibitions, where everyone can “use” the device and hold it in their hands, moving away from the stand by the length of the protective cord.

Card reader

This interface is called, it is designed for connecting memory cards of various formats, such as SD, microSD or SDXC. Memory cards store information such as photos, videos, text data, or any other such type.

PS/2 port

This connector is called PS/2, it is designed to connect a computer keyboard or a wired computer mouse. Found in computers, laptops, monoblocks. Recently, it has been used less and less, due to the transition to wireless types of connecting relevant devices.

S/PDIF port

- used to connect a digital optical audio cable.

DVI port

DVI interface intended for transmitting video data to a monitor or TV. Mainly found in computers or televisions. There are several types of DVI ports, DVI-A is designed to transmit only an analog signal, DVI-D allows you to transmit digital data, DVI-I allows you to transmit both an analog and digital signal.

eSATA port

eSATA— serial interface for data exchange with information storage devices. Used for external implementation of the SATA interface. Can be used to hot-plug a hard drive (BIOS requires AHCI mode). There is also a combined eSATA+USB connector.

COM port

COM– the so-called bidirectional serial interface. Currently, it has practically ceased to be used in computers. Previously used to connect network equipment.

LPT port

LPT- an international parallel interface standard for connecting peripheral devices of a personal computer, such as a printer. Currently not in use.

What are these or those computer connectors on the back wall for? How to connect a monitor? Where to plug in a microphone or multi-channel acoustics? Read about all this in the article on computer ports.

If you ask older people or not very advanced users what a computer is, they will, for the most part, point to the monitor. But, we know that a computer is what is located inside the system unit (which some call a processor :))).

However, even the most modern workstation or gaming PC is not self-sufficient and cannot function without connecting various devices to it. At a minimum, we need a monitor, a mouse and a keyboard... However, this is not all that can be connected to a computer. On its back wall there are a bunch of connectors that allow you to connect literally anything!

You most likely know the purpose of the most common ports, but each one has a couple of “holes” whose purpose is questionable. If you want to know everything about computer connectors, then the article below is just for you.

Minimum set of connectors

The set of ports on the back of your computer may be different for everyone. It depends on how old the PC is, who the motherboard manufacturer is, or what expansion cards you have installed. However, there are some connectors that are present in everyone:

1. PS2 ports for mouse and keyboard (in modern PCs they may be absent or represented by one combined port).
2. Connector for connecting a standard monitor (VGA or DVI).
3. RJ-45 network port for connecting to the Internet or local network.
4. Multiple universal USB ports.
5. Audio card connectors (if installed).

You can also add to this list the power connector on the power supply (usually located at the very top of the system unit). However, in essence, it does not serve to connect any peripherals to the computer and must be a priori to ensure the operation of the PC.

All of the above ports are usually found on the motherboard. However, there are boards that, for example, do not have separate connectors for a mouse and keyboard or do not have video/audio card connectors. In this case, the missing ports can only be compensated by connecting the appropriate expansion cards to them. You won't be able to work on a PC without them.

True, there is one nuance. Instead of connecting new boards, you can use external devices that replace them in functionality. You can connect such devices (for example, a USB mouse and keyboard or an external video card) to your computer using universal ports.

Universal connectors

Serial port

Even when there was no talk about personal computers, developers were already thinking about creating a universal interface for connecting various peripheral devices. So, at the end of 1969, the RS-232 standard (abbreviated as “Recommended Standard”) appeared, which was a 9-pin (less often 25-pin) connector, commonly called a COM port or serial port:

Initially, a COM port (from the English “communications port”) was used to connect a console to a computer, replacing a monitor. With the advent of traditional displays, they began to connect a mouse or modem to it. And with the spread of PCs, the serial port began to be widely used to connect various equipment, such as barcode scanners, cash registers, video surveillance consoles, etc.

Nowadays, this connector is practically not used, since it has been replaced by a more advanced USB port. At various enterprises where RS-232 is still in use, they often use an external COM port in the form of a USB adapter.

Parallel port

Another anachronism that can be found on some motherboards is the so-called parallel port or LPT (abbreviated as "Line Print Terminal" - "print terminal port"):

As the name suggests, this connector was originally (in 1981) developed as a standardized port for connecting printers, scanners and similar devices. This port earned its popular name “parallel” because, unlike a COM port, it could transmit several data streams in parallel.

The standard LPT connector, which can usually be found on not too old PCs, has 25 pins. Because of this, it is often confused with a 25-pin COM port. However, there is a significant difference between them: the COM port is always of the “male” type (with pins), and the LPT is of the “female” type (with holes):

Like the serial port, the parallel port over time began to be used not only for connecting printers. With its help, for example, it was possible to organize direct data transfer from computer to computer, connect storage devices, as well as various control, measuring and signaling devices.

USB

In modern computers, the parallel port, like the serial port, has almost universally been replaced by faster and more modern connectors. The main one, without a doubt, can be called USB (abbreviated as “Universal Serial Bus”), which appeared in 1995 and is still relevant today:

As the name suggests, USB transmits data serially, but at a higher frequency than an older COM port. Due to this, in modern connections based on USB 3.0, it becomes possible to achieve data transfer rates of up to 10 Gbit/s (Super-speed mode). True, the most common USB 2.0 works much slower and provides one of three modes:

• Low-speed - from 10 to 1500 kilobits per second (printers, scanners, mice and other input devices).
• Full-speed - from 0.5 to 12 megabits per second (video capture devices, external audio cards, modern printers and scanners).
• High-speed - from 25 to 480 megabits per second (external video cards, external hard drives).

There are quite a few modifications of USB ports, which indicates their demand and popularity, however, in computers you can usually only find type A connectors. On motherboards that were produced before 2011, you can only find USB 2.0 ports, however, modern PCs can be are also equipped with USB 3.0 ports, which are marked blue or red.

USB is truly universal. Having only 4 conductors (5 more were added in version 3.0), this connector allows you to simultaneously transmit and receive data, as well as power connected devices with a current of 5 volts (500 milliamps for versions 1.0-2.0 and up to 1 ampere for 3.0). This made it possible to use USB in almost any device that can be connected to a PC.

FireWire

However, not only USB is relevant today. In the same 1995, the IEEE 1394 specification was born, which became known under the FireWire brand from the well-known company Apple:

Initially, FireWire was conceived as a high-speed external interface for transmitting and processing multimedia data on the fly. This was facilitated by a throughput of 100 to 400 megabits per second. Subsequently, the speed was increased first to 800 Mbit/s, and later to 3.2 Gbit/s. This made it possible to use the port to create gigabit local networks and connect external hard drives.

Despite the good potential and obvious gains in data transfer speed, FireWire is still much less widespread than USB. And with the advent of high-speed USB 3.0, we can assume that this connector will remain niche and will be used only in professional equipment.

eSATA

Another “player” in the fight for versatility among computer ports is the eSATA connector (from the English “external SATA”), which appeared on the market in 2004-2005, almost 10 years later than USB and FireWire:

This port is primarily intended for connecting external hard drives and provides data transfer speeds of up to 3 Gbps. At the beginning of development, the port (like regular internal SATA) did not have its own power supply, however, almost all modern motherboards with this connector use the eSATAp specification ("p" - "power").

A characteristic feature of eSATAp is its compatibility with standard USB type A plugs. The internal bus of the connector has a similar 4-pin wiring and provides +5 Volt power. The external terminals in the side recesses of the port are supplied with +12 Volts. True, laptops do not have them due to irrationality: the maximum output voltage of standard laptops usually does not exceed 5 Volts.

eSATA is unlikely to be a strong competitor to USB and FireWire in terms of versatility, but it has a huge advantage when it comes to connecting hard drives. The fact is that when connecting external storage devices via the same USB, the signal must be recoded into SATA or PATA commands. Which takes extra time. eSATA transfers data immediately in SATA format, so there are no delays.

Video card connectors

So, I hope we have figured out the main common universal connectors on the back wall of the computer. And now it’s the turn to deal with ports for more specialized purposes. And in the first row here are the monitor connection interfaces that are available on the PC video card.

First of all, it should be said that video cards can be built-in (integrated), discrete (usually on the PCI-Express bus) or external (connected via USB or FireWire). The most productive solution is separate video cards, which are supplied as an expansion card for the internal PCI-Express port:

The advantage of integrated video cards is that the computer is ready to connect a monitor out of the box, and also that they, as a rule, consume significantly less energy than discrete ones. Some video cards are the best in terms of performance because they either do not consume PC resources at all or use a small amount of RAM for cache.

External video cards are usually used by owners of laptops with weak built-in graphics for gaming or working with video and 3D. In theory, they can be no worse than discrete ones, but the type of connection may impose its own limitations. For example, an external video card of the same model as a discrete one connected via a USB 2.0 port will work much slower...

Naturally, depending on the type of your video card, it may or may not have some connectors. Let's look at them all briefly.

VGA (D-Sub)

One of the oldest (developed in 1987) video card ports is the 15-pin analog video output VGA (Video Graphics Adapter) or D-Sub (D-subminiature). "D-shaped subminiature"):

This port is usually present as the only video output on integrated video cards (although modern integrated cards can be equipped with other connectors). It allows you to connect CRT monitors to your computer, as well as most LCD displays and projectors. The maximum video resolution from the port is 1280×1024 pixels.

S-Video (S-VHS)

Another old analog port that is often found on video cards is the S-Video connector (abbreviated as “Separate Video”):

This port was developed in the late 80s by JVC to connect their VCRs and camcorders to a PC. The connector got its name because it made it possible to transmit separately such video signal components as brightness and color. Due to this, the resulting image could be adjusted quite flexibly, adjusting its colors and saturation separately.

In fact, this connector was one of the first attempts to create something like a video capture card for digitizing an analog video signal. At that time, the S-Video bandwidth was sufficient to transmit a regular television signal (the connector, alas, is unsuitable for modern HDTV).

The port initially existed in a 4-pin version, and in the 90s its expanded version with 7 pins appeared. This version made it possible to implement direct compatibility of S-Video with composite connectors of household appliances (TVs, VCRs and cameras) of the RCA type ("tulip").

DVI (abbreviated as "Digital Visual Interface" - "digital video interface")

In 1999, when it became finally clear that the future lay not in analog technologies, but in digital ones, monitor manufacturers decided that VGA (manufactured in 1987) was outdated and issued a new standard, which was called DVI:

There are two types of DVI ports: DVI-I (supports analog VGA signal) and DVI-D (supports only digital signal). They differ in the presence (or absence) of four additional contact sockets on the left side. But there are already 5 types of plugs for DVI connectors:

1. DVI-I Dual Link is a plug with the most complete set of contacts. Supports transmission over one analog and two digital channels.
2. DVI-I Single Link - 9 central contacts are missing. Supports transmission over one analog and one digital channel.
3. DVI-A is a connector for transmitting data over only one analog channel. Used in DVI-VGA adapters.
4. DVI-D Dual Link - four pins on the left side have been removed. Supports transmission on two digital channels only.
5. DVI-D Single Link - four contacts on the left side and 9 in the center have been removed. Supports transmission on only one digital channel.

Modern video cards are usually equipped with a DVI-I connector, to which you can connect any DVI plugs. However, sometimes they skimp on compatibility with analog devices and install DVI-D. In this case, you will only be able to connect a fully digital monitor to your computer. The maximum video resolution from the port is 2560×1600 pixels.

HDMI (abbreviated as “High Definition Multimedia Interface”)

The introduction of DVI solved the problem of direct digital video signal transmission to the monitor. However, in practice the connector turned out to be quite bulky and not very convenient. Therefore, already in 2002, an association that included such large companies as Hitachi, Panasonic, Philips, Sony and others developed and implemented a new HDMI standard:

The HDMI port got rid of support for analog devices, decreased in size by almost half and gained the ability to transmit not only a video signal, but also multi-channel audio. In fact, HDMI has become a digital analogue of standards such as SCART and RCA (colloquially “tulip”).

In terms of technical characteristics, HDMI is the same as DVI-D, but with additional audio conductors. The maximum video resolution from the port is 2560×1600 pixels.

DisplayPort (from English "display connector")

Today, the newest and most promising is the DisplayPort connector, developed in 2006:

Like HDMI, DisplayPort can transmit both audio and video simultaneously. However, its maximum video resolution is higher and is 3840x2400 pixels. Also, due to the increased bandwidth, DisplayPort can transmit a 3D video signal to a TV or monitor.

There was also a version of the miniDP connector, however, today it is practically not used. You can find such ports, perhaps, in MacBook laptops from Apple. Regular DisplayPort has been an almost mandatory connector since 2010, so it can be found both on modern video cards and on any video equipment.

Audio card connectors

If the connectors of video cards differ in appearance and you can immediately determine what kind of port is in front of us, then on sound cards almost all sockets are ordinary “mini-jacks”. It is also complicated by the fact that each port has one-way data transfer only to the input or output.

Usually, the color coding of the ports allows you to understand the connectors. However, there are audio cards where all the connectors, for example, are black, and you can only understand where and what by reading the labels or instructions. Let's try to figure it out by combining knowledge about color and text markings.

MIDI port (from the English "Musical Instrument Digital Interface" - "digital interface of musical instruments")

Let's start, perhaps, with one of the oldest and noticeably different connectors in appearance - the game port:

The port is labeled DA-15 (15 pins) and was originally developed in the 80s to connect various game controllers, such as a joystick. With the spread of MIDI technology, this port was also adapted for connecting musical instruments (mainly synthesizers). For this purpose, a special MIDI cable with an adapter for DIN-5 plugs was used.

Nowadays, joysticks and most musical instruments have switched to the USB bus, so today a MIDI port is not common.

S/PDIF or S/P-DIF (short for "Sony/Philips Digital Interface Format")

In the 90s, personal computers and semi-professional consumer electronics began to spread widely throughout the world. There was a need to switch them, so around this time, top-end sound cards began to be equipped, in addition to other connectors, with an S/P-DIF port:

This port is designed to connect audio equipment (or audio outputs from video cameras and VCRs) using one of two types of cables: optical (TOSLINK specifications) or electrical coaxial (RCA (“tulip”) specifications).

Nowadays, S/PDIF is used mainly for outputting PC audio to semi-professional and professional-level audio reproducing equipment. Supports surround sound transmission in Dolby Digital and Digital Theater System (DTS) formats.

Mini-Jack

Here we come to those connectors that are found on any sound card (unless it is a highly specialized professional board for S/PDIF, of course). I mean those multi-colored mini-jacks, of which there are usually from 1 to 6 (there are also 8 and even 12, but these are special cases that are not so common):

The most common sets of minijacks are 1, 3 and 6. If there is only one port, it is usually intended for connecting speakers or headphones and is called a line output. In some laptops, the line output is combined with the microphone input using an additional contact.

A configuration of 3 mini-jacks is the most common on inexpensive and built-in audio cards. They typically provide a line output (light green), as well as line (blue) and mic (pink) inputs. The difference between line and microphone inputs is that the sound received by the microphone goes through additional processing (noise reduction), while in the linear there is no processing.

Finally, there are audio cards with 6 mini-jack connectors. Here, three additional outputs are added that allow you to connect a 5.1 or 7.1 speaker system to your PC. The color marking of additional ports may vary from manufacturer to manufacturer, but most often we have black, orange and gray. They connect the side speakers, subwoofer and rear speakers, respectively.

If all the connectors on the sound card are the same color, then they will definitely be labeled with port symbols:

1. Microphone input: Mic In or Mic.
2. Line input: Line In or Line.
3. Line output: Line Out, Out, Speaker or Front (means front speakers of multi-channel acoustics).
4. Side speaker output: Side Out or Side.
5. Subwoofer output: Sub Out, Sub or Sbw.
6. Rear speaker output: Rear Out or Rear.

Based on the above inscriptions, you can connect any audio devices to your computer without any problems.

conclusions

Initially, I planned to write a short review article about the most common computer connectors. However, with a more thorough study of the topic, many nuances began to emerge, without mentioning which I could not say that I had told all the most important things. Thus, the article turned out to be quite weighty...

Unfortunately, it is impossible to consider all possible ports even within the resulting “sheet”. Therefore, I limited myself to only those that can be found on computers most often, paying close attention to multimedia and universal connectors. In practice, with the help of additional expansion cards, you can equip your computer with literally any interface you need!

I hope the article will be useful and will be useful to anyone who is thinking of connecting this or that device to a PC. With that, I say goodbye and wish everyone less confusion in computer matters and in life in general :)

P.S. Permission is granted to freely copy and quote this article, provided that an open active link to the source is indicated and the authorship of Ruslan Tertyshny is preserved.

External devices are connected to connectors and sockets located on the outside of the PC system unit (back and front sides) or laptop (sides or back):

The response connectors look like this:

Power cables(220 V)

power unit ASUS laptop

PS/2 plugs for connecting a keyboard (purple) and mouse (green).

LPT cable. The LPT (parallel port) port was mainly used to connect printers. Modern printer models provide connection to a USB port.

COM cable. COM port (serial port) is mainly used to connect modems.

USB cable. The USB port was developed later than the above ports. Most peripheral devices are connected via the USB port: modems, printers, scanners, flash drives, portable hard drives, digital cameras, etc.

VGA cable. Used to connect a monitor. Cable for connecting to the Internet (Intranet) ( RJ-45 connector)

Slot connector types used on the motherboard (ISA or EISA, PCI, AGP):

Slots with PCI connector (female):

and sound card with PCI connector (male):

PCI connectors used to connect an internal modem, sound card, network card, SCSI disk controller.

ISA slots (Mother). The ISA interface is deprecated. In modern PCs, it is usually absent.

PCISA FlipPOST diagnostic board with connectors PCI and ISA (male) PCZWiz company

Slot with AGP connector(dad is at the top, mom is at the bottom).

The AGP interface is designed to connect a video adapter to a separate bus, with output directly to system memory.

UDMA slot(father is on the right, mother is on the left).
Hard drives and more are connected to it.

It should be noted that each slot type has its own color. By opening access to the motherboard, you can easily find your way around. But it’s better that you don’t need it. But the cables that connect external devices to the PC “you need to know by sight.” Remember that the mother and father of the connector must be the same color. Always remember to match the colors of the male and female connectors or know what the colors of the connectors on the PC (laptop) case indicate.

Take, for example, a standard sound card:

Linear audio output to the speaker is always green.

The line input for audio amplification is always blue.

The microphone connector is always pink.

Match them with plugs:

The color design of the connectors will help you. True, colors among PC manufacturers are not unified. For example, some may have a purple keyboard connector, while others may have a red or gray one. Therefore, pay attention to the special symbols that mark the connectors. In this case, it will not be difficult for you to find out.

Decoding computer connector symbols

Appearance of computer and laptop ports

The interface cables for external devices are unique. You cannot insert it into another connector on your PC (the design and number of sockets are different). All this will help you move your PC (laptop) from place to place without prompting from anyone. You will be able to connect devices and cables to your PC correctly. I hope that the material presented will help you with this.

Now let's look at each connector in more detail. Let's start from top to bottom in order. First on the list will be socket for connecting the power cable: Standard power cable, this cable connects all computer devices, from printers and scanners to faxes and monitors. A very convenient cable, differing only in the length of the wire and the thickness of the wire section. Accordingly, the thicker the cable, the greater the load it can withstand. PS/2 connector used for connecting mouse and keyboard. In their visual appearance they are absolutely identical, the only difference is in their color. The green port is for connecting a mouse, the purple port is for connecting a keyboard. In modern motherboards you can find one PS/2 port, which is painted in two colors at once, green and purple, which means that you can connect either a mouse or a keyboard to it. COM port– was once used to connect a mouse, modems, scanners. Now this port is practically not used. Over the past 7 years, I have had to use this port several times. To connect temperature sensors to it. It was through this port that the data accumulated on it was read. I also connected an attachment for satellite dishes through this port (updating the firmware). VGA port – for connecting a monitor. The port is very similar to the previous one, but has three rows of contacts and is always painted blue. This port has been used for connecting monitors for many years. Now new video cards with a DVI port are being actively introduced (photo on the right). When choosing a monitor with such a cable, I advise you to carefully check which DVI port you have on your motherboard, since there are at least five different types. LPT port– previously used to connect a printer or scanner. Now this port is obsolete and no one uses it. The outdated LPT port has been replaced by a new, more functional USB port. In modern motherboards this port is not installed as unnecessary. USB port- The most widely used connector in any modern computer. You can connect a mouse, keyboard, camera, flash drive, printer, scanner, video camera and much more to this connector. There are two types of USB ports – USB 2.0 and USB 3.0. The USB 3.0 port has a blue color inside; this port has a higher throughput speed. USB 2.0 ports are white and black. Network port – for connecting a network cable. A cable from the provider that provides you with Internet service is connected to this port. The same ports are present on your router (if you use one). This port can be used to connect audio devices. For connecting speakers, headphones, microphones, etc. Red connector for connecting a microphone, green connector for connecting speakers (headphones), blue connector for line output (for transmitting an audio signal to another device).

Hard drive connectors

In the process of computer development, HDD or hard drive changed several connector specifications; for many modern computer scientists, names such as IDE, SCSI and their modifications are already history. The dimensions of the hard drive have also changed significantly; the first bricks I had to work with weighed more than a kilogram!

At the moment, the following hard drive connectors are relevant:

The SATA connector is the most popular nowadays; hard drives with this interface are found in computers, laptops, servers, video recorders and other computer equipment.

There are from 4 to 8 SATA connectors on the computer motherboard. Not only hard drives are connected through this interface. CD-ROM, DVD-ROM drives also use it.

MSATA connector— Variety SATA connector, designed specifically for solid state drives (SSDs), which have replaced mechanical hard drives. SSD drives with this interface are found in computers, laptops, servers, video recorders and other computer equipment.