Internet connection
Fragments of microelectronics are now stagnating almost everywhere, and developments are taking place at a great pace, the situation has been reduced if standards and transmission interfaces are constantly being compromised.
A number of more modern interfaces, such as RS-485, are in use and older ones, for example, RS-232. Let's take a look at the features, advantages and shortcomings of some of the most popular ones. RS-232
(Recommended Standard) is still victorious in the impersonality of computer devices
digital technology
However, if the current equipment is released with the help of new interfaces, the RS-232 fragments will no longer serve any purpose.
Although very similar in its characteristics to RS-422, however, the emergence of much greater width in all types of electrical equipment is due to the fact that on this basis there is a possibility that all devices can not only receive a signal, but also transmit it.
This is due to the fact that RS-485 is a full-duplex interface and devices do not conflict with each other.
It also features a high maximum data transmission speed - 10 Mbit/s - and a long-distance connection - up to 1200 m. The network can accommodate 32 devices with standard support features. Since the network has less support, it is possible to combine one network with up to 256 subscribers. CAN
The CAN interface is a full-duplex interface with a maximum data transmission speed of 1 Mbit/s. Like RS-485 and RS-422, signal transmission uses a differential pair. CAN is characterized by even high resistance to the transfer of the channel and a large number of checks for errors, which is why the reliability of their culpability is almost equal to zero.
Vikorist is involved in the organization of measures, where we first need a reliable connection.
Just like in RS-485, CAN can have a number of transmissions. The USB interface is affected by high data transfer speeds, especially in remaining versions
(USB 2.0 – 480 Mbit/s, USB 3.0 – 4.8 Gbit/s).
However, the distance between the surface and the stagnation everywhere is very short (about 5 meters).
When using a USB connection, you can create a point-to-point connection.
Other types of interfaces are also explored.
We have great respect for the internal interfaces found on the PC case.
Internal interfaces
1.SATA
This is an updated version of the old ATA. For additional SATA, storage devices are connected to the motherboard, for example, hard drive 
.
As a rule, this is the internal interface, otherwise it is called out.
2. ATA/133 (Parallel ATA, UltraDMA/133 or E-IDE).
This is a parallel bus. It is required to transmit the signal from/to hard and soft drives. Drotya has forty contacts.
With this help, you can connect up to two devices at the same time, operating in the “slave” and “master” modes.
The cable has a small protrusion on one side, so it’s simply impossible to connect it “in the wrong way.” However, with old wires there may be such a protrusion, so, in order not to have mercy, remember the rule. The color scheme, applied on one side of the dot, may coincide with contact No. 1 on the motherboard. 3. AGP. There is a special bus for connecting a video card.
AGP is important
old version PCIe has come to replace it..
No less, this interface can be expanded, since a great number of platforms have been released under it.
The interface has a number of versions, the remaining ones – AGP 8x – have a throughput of 2.1 GB/s.
4. PCI and PCI-x.
Standard parallel buses, in addition to which the meshes and
sound cards
, modems, pay for stored video.
The largest power supply among computer users is the PCI 2.1 bus with a throughput capacity of up to 133 Mbit/s.
PCI-X has a lot of features, which is why we're talking about
motherboards and work stations and servers. 5.PCIe. The tires described in the fifth paragraph have a similar name. This is not a parallel, but a serial interface. 
2. "Tulip" (Cinch / RCA).
These roses show different colors depending on the type of signal (sound, video, brightness, etc.).
3.PS/2.
We connect them as they are used in stationary computers to connect a bear and a keyboard.
They are characterized by the following code: green color - Misha, purple - keyboard.
If you mix them up, nothing bad will happen, you just won’t connect to the device properly.
To rectify the situation, simply change the forks in places.
4. DVI.
A slot for a monitor that transmits digital signals.
5. VGA.
A monitor is connected to the additional Video Graphics Array connector.
There are blue, green and red colors used for transmitting information.
6. RJ45 for LAN and ISDN.
A fencing port that is used for connecting to Ethernet.
7. RJ11.
The port used to connect to the modem.
Similar to RJ45, but with fewer contacts.
8. HDMI.
This is a multimedia digital connector suitable for HDTV signals with a maximum resolution of 1920x1080.
New products have a copyright protection mechanism (DRM). It’s cool that even though you’re using an HDMI cable, you can’t stretch fifteen meters. 9. SCART.
From the very beginning, one important thing is to clearly separate the connection interface and the data transfer interface. With some dart devices, this feature can be used to equip a mouse, keyboard, or other device that is tightly connected with a cable to the output port.:
For drone-free peripherals, the connection interfaces are limited to the same PS/2, COM, LPT, USB, etc., but only the receiver is connected to the port, and the mouse itself exchanges data with it via an additional radio channel or infrared exchanges.
Knit here tightly myth the first Droneless devices are completely different from wired ones.
It's not true.
Regardless of the specific data transfer interface, the mouse is connected to the PS/2 port (either directly or through the receiver) for the computer using the “PS/2 Bear”.
The computer began to work out the differences between them at the same time as “simple” receivers. The situation becomes more complicated at the Bluetooth connection, but through those in which it is not the passive receiver that is stuck, but the Bluetooth adapter and the peripheral device itself. , not at all simple, And the axis here has already begun to fail: the separate part has 320 x 200 pixels, which looks funny, the screen has already 64 thousand addressable positions, so if you need to It’s easy to waste water in any way, without keyboard keys you'll get by. Those PZ developers realized that the graphics are not only bad in games. graphic editors
: how to acquire a graphical interface to the basic program, which is not practical, and the axis for mastering the unprepared system is shorter, less textual.
Well, for work in graphic environments, the most suitable one is the Misha, which has been specially divided up for this purpose, and in the meantime there was no choice: either the Misha or the light pen, which can lead to less accuracy, less These are the first mice.
Alas, bad luck does not have a special teddy bear port for the PC!
Even in those shaggy rocks of my life (for whom it is already practically impossible to understand at once), a wonderful idea came to mind.
In fact, every computer has, for example, one serial port on which you can connect as much as possible. Why can’t you buti Misha? there was more than enough for all traders. It’s not surprising that many of us, having started to work on computers equipped with such mice themselves, and with their help, mastered the first versions of Windows systems for the PC. Moreover, such targets can be concentrated until now, although many companies are no longer disrupted, and the decision has significantly shortened their share (for example, Genius has no more than 10% of the target mass, and Microsoft and Logitech don’t cut your necks at all).
In 2000, such a mouse can still be easily purchased, but just going to the market is not enough: the latest mice from Genius, A4 Tech and other companies are being bought up quite quickly, since in rich places they are still selling but old computers can cope completely with your own treasures, and not work with new mice.
Those long-released mice with the latest interface can be quite sharp, which has a lot to do with the fact that at that time not a lot of trees were larger and technology was more reliable.
Back in 1987, when the launch of the PS/2 line began, IBM bought all the advances.
Unfortunately, they created new ones, so that the architecture, revolutionary at that time, ingloriously froze a few rocks, until it died completely. Alas, they are still called mini-DIN ports for keyboards and mice, which were started by this line itself. So in these computers a special mouse port appeared, and mouse support was sent to the BIOS (both in the original case and in the ABIOS).
The government structure was destroyed in 1997.
By dissolving the ATX standard, Intel, wisely, took advantage of the elasticity of the mouse, so that the PS/2 type port became an obligatory accessory of a computer that claims to be new.
Well, since everyone has a port, why not use it quickly? Motherboards in the AT format, however, were widely known on the market, and soon became a mandatory component. Thus, mice with the PS/2 interface quickly became a standard. USB mice Meanwhile, having given PS/2 a green light, Intel quickly tried to turn the process of the new rack around.
Well, the supply of USB mice to the market has become more feasible.
However, it’s even easier to ensure connectivity between USB and PS/2, since the remaining buses are insured for 5 V, so it’s true that USB mice have begun to conquer the place in the sun: it turned out that It is not obligatory for them to release models that are only insured With one interface you can practically provide support for both for the same amount of money. The first to “sell” were the box mice, especially those models that were not planned to be released in the OEM version: it’s not cheap to buy them in any situation, or two or three tens of cents for an adapter for two or three (or even five) (sixty) tens of dollars, don’t waste time.:
For OEM companies, they chose USB as the main standard, and an adapter (for those who need it) can be added independently.
However, the majority of mice are based on these same controllers, with a more complex design to support USB, and a number of “middle class” mice will continue to be released and have a version for PS/2 (packed with oh, there are many varieties), and the models oriented We haven’t started switching to USB yet in the budget segment. The world has a growing number of special teddy bear controllers supported only by USB, this interface will gain new positions, and now the PS/2 port can be installed painlessly and without marking anything. Before speaking, about old ownership and, obviously, about old programs. She's been sleeping for a long time myth is different
USB drives do not work with DOS, Windows 95 and NT4.
They appeared quite recently both in the historical and computer worlds. Ale with them already knitted:
myth three
Mishas with a Bluetooth interface are analogues of basic droneless models with a radio or IR interface. In fact, it is no more a myth that Bluetooth is not a data exchange interface, but a connection interface. Introduce into confusion those that such models are now equipped with Bluetooth adapters, just like the original ones dartless models supplied together with receivers. In addition, for example, the Logitech MX900 at first glance is in no way different from the MX700: it’s the same mouse, the same base, only it uses Bluetooth, which, in fact, is the same radio communication (the frequency increases, but and at a frequency of 2.4 GHz they work richly radiomish models). However, the adapter is not at all a simple converter of a wired to wireless interface. This is a useful adapter that allows your computer to work with Bluetooth devices.
And one of them (if it appears consistent with the profile) may be a mouse.
Theoretically, these models can work with adapters that are included in the package, and they themselves “don’t know” what the adapter is: a built-in one, on the PCI bus, or most USB extensions. And in the end it is not possible to draw parallels with dartless mice
, receivers that are connected to the USB port - this pretty I don’t mind, the fragments of the coral XP and the subsequent target are unknown to me, I don’t want to die out myself, since no one needs it, and the maximum possible value is still impossible to determine, the fragments will be manually Unfortunately, you don’t regulate the frequency of the experience. With USB there is manual control when Wikoristannya Windows
It is impossible (acknowledged, the methods of its extinction are still unknown), the frequency of training will never be possible.
And this is the current situation for each PS/2 port - the usual results are under 9x, so that we can gradually expand into the world of a fully-equipped OS, but not reach USB, and as much as 200 Hz maximum (the repeat is higher, lower than USB!) with manual adjustment i.
You can get a little lost here. Since PS/2 will provide the highest frequency, then what about USB?:
The axis is yours
myth of the fourth
For gaming you definitely need a mouse with a PS/2 interface - you are guaranteed to achieve the best results.
On the right, in what we saw above the frequency of the port.
However, Misha herself may appear unpaid to see tributes with such splendor.
And it turns out that the “crap” PS/2 Misha will really give you 80 Hz (older drone-free models did not reach more than 50 Hz), while the “good” USB honestly delivers its 125 Hz.
If the mouse's operating frequency is set to more than 100 Hz, it's all the same to which ports to connect to, and there's no need to run PS/2 under XP.
If you want the most beautiful (from a gamer's point of view) PS/2 mice can effectively adjust the position at 200 Hz or close to that, and allow you to obtain maximum accuracy from the game, but not make it a rule. In real minds, everything, most often, comes down to the fact that PS/2 has greater potential, which is worth remembering., but your axis will not work, which means everything, will not be (which is why a lot of people started immediately after these adapters appeared. However, the collar butts are tightened deyaki mice (mostly recently released) s active Use adapters, but there will be no culprits, as a rule.
Mishas with a PS/2 interface, obviously, simply connect to the output port. To connect them to USB, you need special active adapters, which is consistent with the fact that most current laptops and desktops desktop computers There are no longer any PS/2 ports. There are no problems with life in this case (and there, and there is 5 V), please use this adapter to transform your mouse and keyboard (how to connect both) to a standard USB device with everything that works zocrema, as special equipment is supplied with the devices security software, then you won’t be able to use it if you use the adapter.
Connect the PS/2 mouse to the serial port in Zagalny Vipadka It’s not possible, but in due course there were more popular models that supported the same standards.
Behind the scenes, there was a small PS/2 connector and an adapter that went into the kit, which was built into the 9th pin COM port. However, not all mice behave this way, and the stench has not been released for a long time.:
So don’t be fooled by the fact that a newly purchased PS/2 mouse can be easily connected to the serial port using an adapter bought on the market, but only up to two-standard mice.
In fact, no matter how you unplug the PS/2 connector: either directly on the cable or unplug the additional adapter from USB, the result will be absolutely the same. The whole design will be much tighter, so you don’t have to touch the cable too much: forget about the hot connection.:
Other powers are similar to PS/2, and are not reduced by USB.
Zokrema, unfaithful
myth sosty
There is no sense in overclocking the PS/2 port when a USB mouse is connected via an adapter, since the actual operating frequency will not rise above 125 Hz.
You don’t have to comment – it’s just a myth.
Those who, having verified, know a lot of models run up to 200 Hz, do not care about those that stink, after all, “at a girl’s place” (by the plug) of USB.
You won't have to look at the power supply - you can connect a USB mouse to the serial port (which, as it turns out, can be done).
If you have carefully read the remaining two parts, then you yourself can explain to anyone why this is impossible.
USB The main goal of this meta-standard is to provide home users with the real ability to operate in Plug&Play mode with peripheral devices.
This means that the device must transfer the connection to the operating computer and automatically recognize it after connecting and installing appropriate drivers. The cream must be supplied to low-pressure life-giving devices from the tire itself. The bus fluidity is sufficient for most important peripheral devices. The historical problem of lack of resources on the internal buses of the IBM PC of a large computer persists - the USB controller takes up only one interruption, regardless of the number of connections to the device bus. Pererivannya Pererivannya - this is the application of a threaded command or a threaded sequence of commands for processing a song. special program a compiler of the interrupted program, with further turns to the Viconnian interrupted program.
This may be caused by a special situation that arose during the program's completion, or by a signal external building . Interruption is designed to allow the processor to react quickly to specific situations that occur when programs are installed and interact with external devices. The interruption mechanism is provided by compatible hardware programmatically
computer. Technical characteristics USB high speed signaling bit rate – 12 Mb/s;
maximum dozhina cable for high speed exchange – 5 m; on the twists of the bet, call it the “zirka”.
The terminology is similar - multiplying buses are also called HUB. Connection diagram USB devices
to the computer, in any device there may be a HUB. The main difference in the topology of a local network is that there may be only one computer (or host device). The HUB can be either connected to a power supply unit or supplied to peripheral devices.
Most often, HUBs are built into the monitor and keyboard.
Cables and connections
USB Scheme
USB cable: GND - to the “body” for the development of peripheral devices;
VBus +5 V – for Lanzyugiv life; bus D+ – for transmitting data, bus D – for receiving data Cables and USB connectors The cable for maintaining full speed of the bus (full-speed) is twisted like a twisted pair, protected by a screen and can also be twisted for operation in the mode of minimum speed (low-speed). A cable for operation at a minimum speed (for example, for connecting a mouse) may be either unshielded. Cables and USB sockets have the following numbering of contacts: Contact number Assignment Color 1 V BUS Red 2 D ‑ White 3 D + Green 4 GND Black Screen Braided
Socket type "A" Socket type "B" Plug type "A" Plug type "B" Which devices are vikorist or vikorist USB In low speed mode: keyboards; mishi; joysticks; dot matrix printers;
IEEE 1394 Interface Name IEEE 1394: Sony: i. Link, Apple: Fire. Wire, Toshiba: S 400 Others: DV in/out The standard for the cable section transmits three speeds of data transmission over the bus – 98.304, 196.608 and 393.216 Mbit/s.
Call ci meanings in
various documents round up to 100, 200 and 400 Mbit/s, vikorista for stylosti values S 100, S 200 and S 400. Main characteristics of IEEE 1394 speed of data transmission up to 400 Mbit/s according to the IEEE-1394 a standard and 800 Mbit/s according to the IEEE-1394 b standard, approved by the 1394 Trade Association for example, published in 2001;
16-bit addresses allow addressing up to 64 K nodes on the bus; The theoretical maximum tire depth is 224 m;"hot" connection/connection without wasting data;
automatic configuration, similar to Plug
The main characteristics of IEEE 1394 are a sufficient bus topology - by analogy with local boundaries, both a “mirror” and a side bus can be distinguished (only in the form of a lanyard, at the same time as a boundary on coaxial cable); no need for terminators at the end of the connector of connecting devices; The operating system, for example, is not guaranteed.
Merezha on IEEE-1394 V operating system Microsoft Windows Millennium Edition, which was released in the spring of 2000, first introduced support for measurements based on IEEE-1394 controllers. Such a measure allows the speed of data transmission to be 4 times higher, lower Fast Ethernet, and very handy for home or small office.
The inconsistency in this case lies in the small limit of one segment, a total of 4.5 m. For this purpose, repeaters are available for 2 or 3 connections. IEEE-1394 Cables and Connectors The standard IEEE-1394 cable is folded into 2 torsion pairs
transmission of bus signals, two life wires, which are placed in a shielded shell.
Conduct life insurance on the circuit up to the second ampere and voltage from 8 to 40 V.
Cables and connectors IEEE-1394 6/6 wire cable, supporting transmission speed up to 400 Mbps.
Mains voltage up to 40 V with current up to 1.5 A. Extension from 0.7 to 4.5 m. Cable with 6/4 wires, boosting transmission speed up to 100 Mbit/s.
Specifications RS 232 (COM port) Standard EIA RS‑ 232‑C, CCITT V. 24 Transmission speed 115 Kbps (maximum) Transmission range (maximum) Character of the signal asymmetrical due to voltage Driver strength 1 Number of drivers Notes 1 Connection diagram duplex, point to point
Specifications RS 232 (COM port) Data (5, 6, 7 or 8 bits) are accompanied by a start bit, a parity bit and one or two stop bits. Having picked up the start bit, the receiver selects from the data bit line at regular intervals. Be very respectful, please
clock frequencies
However, when accepting and transferring the bullets, separation is permissible - no more than 10%.
The transmission speed via RS-232 C can be selected from a range of: 110, 150, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps. All RS‑232 C signals are transmitted by specially selected levels to ensure high resistance to communication failure.
It is important that the data is transmitted in inverse code (a logical one indicates a low value, a logical zero indicates a high value). mobile phones. Remains most important, fragments Stilnikov phone
This is the most advanced way to access the Internet from a laptop. The transmission speed through the infrared port reaches up to 115.2 Kbps. The laptop can have two infrared ports: one for establishing a connection with other digital devices, and the other one is for the remote control
remote therapy(Fig. 4.5).
The “Vichko” port assigned to the remote control may be located on the front end of the laptop, or perhaps an external one (in this case it is “attached” to the USB port). The remote control (in common parlance – “linyvchik”) is used when using a laptop as an audio player for video files.
For other purposes, the IrDA port for the remote control cannot be used: communication with digital devices cannot be ensured. Small 4.5.
You can connect a remote control to the laptop, which will make it easier to carry out a presentation. Bluetooth– devices that transmit data at speeds up to 722 Kbps will certainly become serious competition for IrDA. Vikoristan radio channel for security dartless connection
Today the word hotspot is in sight, perhaps, in full. This is the name given to a remotely accessible area with Wi-Fi coverage, a place where you can come with your laptop and connect to local network resources (connect to the Internet, or other options). Access can be free of charge, paid, or given to the best of our ability (for example, to a restaurant that asks people to drink).
Today, in Zakhad, such points can be found in all major hotels, train stations, airports and other public places.
mobile correspondents
: at many cafes, restaurants, Internet cafes, libraries, business centers (div. sites www.jiwire.com, www.wifinder.com, www.totalhotspots.com and others).
Zones with Wi-Fi coverage (both paid and cost-free) are becoming increasingly widespread in Russia.
Sites with information about the development of such points in various places (for example, www.freewifi.ru, http://wifi.yandex.ru or http://wifi.ru/) are becoming one of the most popular categories of Internet resources. One look at its passage is enough to understand: connecting via Wi-Fi is not a European or metropolitan “thing,” as long as the access point can be found in most places in any country., To which you can connect almost all current peripheral devices.
The USB 2.0 interface ensures data transfer at speeds up to 60 Mbit/s and is comparable to USB 1.1. This term means that up to USB 2.0 ports you can connect devices that support USB 1.1, and these devices will function correctly, although the speed of data exchange will not exceed 12 Mbps (total If so, the “younger” version of the standard will be provided) . Equipping a laptop in good manners FireWire ports(The official name of the interface is IEEE 1394, known as i.Link). This interface is not necessary, but may become manual when connecting peripheral devices that involve intensive data exchange: digital video cameras, devices for reading memory cards (Card-Reader), external hoarders(both CD and DVD drives, and based on
hard drive ), digital cameras with great sensors, etc. Data transmission speed via FireWire is up to 400 Mbit/s.і Types of ports of older formats – LPT,COM
PS/2
(they are called legacy - downgraded) - laptop manufacturers are gradually being released. That’s right, fewer and fewer people work, for example, with printers that connect to LPT, and with mice that use a COM interface. With such a rank, it is no longer practical to become stagnant, but koristuvachev will have to attract additional vantage.
Don’t forget to become less than a few tens of grams, but still... Vinyatok – PS/2 port.
Its presence in the laptop is still relevant. First of all, USB keyboards can be compared to the price of a PS/2 keyboard. In other words, there are still a large number of mice that are connected through this interface, and any user will be able to use the same manipulator. All laptops are secured The Ai‑Box proprietary interface has been installed, which allows you to connect disk drives.
However, the range of peripheral devices that connect to firm interfaces is innumerable, they are not very wide and they are expensive to purchase, so it is rare for them to become stagnant.
When choosing a laptop, pay attention to the mutual arrangement of ports (Fig. 4.7). Since their connectors are distributed close to one, it will be difficult to handle: connecting one external device can practically block access to other ports.
As practice shows, there is no harm in interfaces that are arranged one above the other: when a device is connected to one of them, the other appears inaccessible.
Small
4.7.
Mutual expansion of the ports significantly affects the handiness of the robot
Porada The laptop is obviously guilty of having more USB ports; Legacy ports are over-the-top, FireWire is used infrequently (if you have a DV video camera, you need such an interface), and proprietary ports are no longer relevant.
Fax modem
Modems for telephone lines are available on all current laptops.
We were not able to find a model on the market that would have a 56 Kbps modem integrated every day.
Laptop modems are nothing special; one type does not change, the speed of data transmission that is achievable with local Russian telephone lines approximately the same.
Obviously, modems installed in laptops can send and receive faxes, but today this form of communication is considered obsolete and is rapidly becoming obsolete by e-mail.
However, fax will continue to be used for transmitting documents, images, etc., so the fax warehouse of the laptop’s communication subsystem will likely continue to be relevant for a long time. It should also be noted that the primary connection through the modem begins to be actively interrupted by ADSL and satellite technologies. Most of the time, you may not need a modem in your laptop.
It’s difficult to evaluate the ease of input-output system, so before opening your laptop, you’d like to type a short text on the keyboard so you can understand and process it manually. Don’t expect any particular comfort when you first get acquainted with an unnamed keyboard, otherwise there is no need to blame yourself for teasing with your fingers on the keys. If the keyboard of the laptop you are planning to buy is disappointing you, better try to find a different model - a keyboard in
mobile computer
It’s made, but it’s impossible to replace it!
Respect!
The laptop keyboard does not have to bend under your fingers when you hit the keys! The type of portable computer that has such a special feature is to be seen. Additional tricks to improve the ergonomics of the keyboard are not available on laptops.
Although the Acer company sometimes arranges the keys on its models in slightly curved rows, it does not change the situation much. On the laptop keyboard, select the additional keys (Fig. 4.8).