Most modern users of computers, mobile devices or television panels have come across a concept such as VGA. What is a connector, video adapter, monitor, driver, cable or adapter? Unfortunately, many of us, as a rule, do not have a clear understanding of this issue. Therefore, it is worthwhile to dwell on this standard in more detail.
VGA: what is it in a general sense?
First, a few words about the standard itself. In its broadest sense, VGA is not a single component listed above, but a holistic component-type video interface, originally developed by IBM for its computers.
Thus, both hardware and software components are included in understanding the entire technology of image reproduction or transmission, and the operation of the interface consists in their interaction.
History of the standard
Now a few words about the appearance of the VGA video standard. What is it, a little understood. Video Graphic Array was first introduced by IBM in 1987 on PS / 2 computers.
The VGA adapter, unlike its predecessors and followers, used (and uses) an analog signal for high-quality image transmission. But along the way, the question arises as to why the introduction of a new standard was needed. For a complete understanding of this solution, you need to turn to the main parameters of the devices themselves.
Main characteristics
The first and one of the main factors in the transition to this standard, most experts call the moment that initially it was necessary to reduce the number of wires in the main cable with the ability to connect system units via the VGA graphics adapter to the corresponding monitors, which were able to transmit much more colors and shades than before. At the same time, a higher resolution of the picture was achieved.
The VGA graphics adapter itself today has a structure that includes the following elements:
- a graphics controller for exchanging data between video memory and a central processor based on bitwise data operations;
- 256 KB DRAM, divided into four color layers;
- serial converter of video memory data into bits for transferring attributes to the controller;
- an attribute controller for converting input data to color values based on a palette;
- synchronizer for controlling layer switching and time parameters of the graphics adapter;
- cathode ray tube controller for generating synchronization signals with a monitor.
Provided that a VGA driver is installed in the system, the maximum resolution leaves 640x480 pixels per inch with a color depth of up to 32 bits. Of course, at the time the standard appeared, it was truly a revolution. But today you can find much greater resolutions, which is achieved through the use of digital technology. But as it turns out, even at the current stage in the development of computer technology, you cannot discount the VGA standard. What does it mean? The only thing is that for the transmission of the image, as already mentioned, an analog signal is used, which can be converted to any other. In addition, the size of the adapter itself is significantly reduced, and it can be integrated directly into the motherboard or additionally into a video card.
Here it is worth paying attention also to the fact that the digital signal has a wider bandwidth, and MPEG encoding technology is used to transmit such a signal. And this, in turn, leads to a loss of quality.
VGA monitors and TVs
Since the appearance of the main standard, the corresponding monitors have been actively used, and after that the television panels of this interface (for example, LCD devices) have been actively used.
Today, such an abbreviation is used to denote all graphic modes, including monitors, which are capable of supporting a resolution of 640x480 pixels, regardless of the hardware component. At the current stage of development, they are practically not used, although at one time they were very popular.
Graphics Adapters
Almost all modern graphics accelerators (video cards), whether integrated or discrete, support the main modes of the described interface and are equipped with corresponding outputs (ports), which are sometimes referred to as D-Sub.
In other words, a video card can have several video outputs. And the VGA-connector is present without fail. By the way, such connectors can be found on the rear panels of stationary system units and on the side walls of laptops.
Drivers
It goes without saying that not a single graphics accelerator will work if the corresponding driver is not installed for it (including the VGA driver).
But for modern video cards, you need to install such control programs not from operating system databases, but from distributions of equipment manufacturers. In addition, today the control or overclocking tools supplied for the most popular NVIDIA and Radeon cards are widely used.
The fact that the VGA driver works correctly, many gamers can verify by setting the video settings in the game settings to 640x480 or its non-standard variations. Actually, the same situation is observed when connecting a computer or laptop to a high-definition TV panel if a VGA cable is used (and not only with the same type of connectors on both sides).
Types of cables and adapters
Since you can find quite a lot of connection options for completely different video interfaces, it is worthwhile to dwell on cables with adapters that can be used to convert image transmission according to a scheme that will be recognized by both the receiving and transmitting devices.
As an example, consider a VGA cable with different transition options. Among the main ones (except for the usual type), the following can be distinguished:
- VGA-DVI (used on some video cards that do not have a VGA connector, although they support the corresponding operating modes);
- VGA-HDMI (can be used to connect older computers or laptops to modern TVs and projectors);
- VGA-RCA or VGA- “tulip” (used to connect modern computer systems that are not equipped with VGA connectors to old televisions or monitors with EBT tubes);
- VGA-HDMI-RCA-mini-Jack (a variation of combining the two previous adapters for connecting with sound transmission - sound is not transmitted through VGA);
- VGA-S-Video (a less popular option for connecting to TVs).
The main connector of the standard, also referred to as DE15F, in any of the options is a 15-pin connector on the one hand, which allows transmitting a signal based on progressive scanning technology in which the voltage change corresponds to the change in the EBL brightness (the intensity of the beam of a monitor’s gun or kinescope).
Summary and conclusions
That's all for understanding VGA. What it is? In fact, this is the interface, and not its individual components necessary for the correct functioning. And as you can already see, it is present in most modern computer devices. Although the prospects for the development of such technologies look rather vague, no one is going to refuse them yet.
It remains to be added that this standard, despite the appearance of its followers in the form of the same Super VGA or XGA interface, still remains one of the most popular and sought-after in the whole world and on all types of devices, including computers, laptops, television panels or even mobile gadgets.