Programming video adapters CGA, EGA and VGA. Monochrome graphical PKD displays for microcontroller circuits Monochrome PKD display

Monochrome monitors it is cheaper for colors, maybe more clear image and a greater diversity of buildings, allow you to imagine dozens of shades of “gray color, less harsh for a healthy person. To that, a lot of professional programmers give priority to themselves.

In the middle of monochrome, they are most often vicorated:

● monochrome monitors of direct carving, which will ensure a high degree of diversity when displaying textual and pseudographic characters, but not suitable for forming graphic images, prompted by okremih pіkselіv; work together with monochrome video controllers;

● Composite monochrome monitors ensure that both symbolic and graphical information is displayed in a dual robot with a color graphics adapter (you can see, naturally, one-color, mostly green or Burshtinov, images).

The largest distribution of buildings with a good transmission of pvttones from monitors, which can be installed at a given hour, can be monochrome composite monitors with black and white images of the “paper white” type (often found in floor viewing systems); їх razdіlna zdatnіst іn a sleeping robot with a good video adapter move 1600 x 1200 pixels.

Color monitors

The color CRT-monitor has three electronic harmonics, while one harmonic is used, which is fixed in monochrome monitors. Skin garmata is available for one of the three main colors: red (Red) greenery (green) and blue (Blue), with a way of changing them, all other colors and colors are created, up to 16 million different colors, transferred by the TrueColor standard. The luminophore of the color tube contains different groups of points, in the skin there are three types of elements (stars and the name of the group of phosphor elements - triads), it shines with the main colors, and the flow of electrons in the skin electronic harmonica is direct on the visible groups of points. Such monitors are sometimes called RGB monitors, after the first letters, name the main colors that form the spectrum.

Electronic promin, appointments for red phosphor elements, is not guilty of pouring green chi blue color onto the phosphor. To achieve such

dії, vikoristovuєtsya special mask, the structure is to lie in the type of kinescopes spring pickers, which ensures the discreteness (disintegration) of the image.

EPT can be divided into two classes:

● with delta-like expansion of electronic garmats;

● for planar expansion of electronic harmonics.

Often, EPT (tubes) with planar expansion of electronic garmats is also called EPT with the same change, so like pouring magnetic field However, when changing the position of the tube of the second field, it is not necessary to carry out additional adjustments. Two types of masks are installed in these tubes: 0 "Shadow Mask" (shadow mask);

● Slot Mask (shіlinna mask).

Tinova mask is the widest type of masks for CRT monitors. A shade mask with a metal mesh in front of the screen of a glass tube with a phosphor ball. Open in the metal grid to be sure to exchange only the necessary phosphor elements and more in the singing areas. The minimum difference between luminescent elements of the same color is called dot pitch. The shade mask is stuck on modern monitors, Hitachi, Panasonic, Samsung, Daewoo, LG, Nokia, ViewSonic monitors.

The shield mask is folded from parallel metal conductors in front of the screen of a glass tube with a phosphor ball. Shchilini between the conductors will ensure that the exchange gets on the necessary smog of the screen. The luminous elements are shaded at the vertical elliptical centers, and the mask is broken from the vertical lines. The vertical smugs are actually divided into elliptical centers, like avenging groups of phosphor elements in three main colors. The minimum gap between two middles is called slot pitch. Width mask victorious, crim monitors by NEC (retailer of this technology), in Panasonic monitors flat screen PureFlat and LG's Flatron flat screen.

Sony has developed flat tubes with aperture grills (Aperture Grill), which are bigger than Trinitron tubes. Aperture grati є metal gratings with vertical lines. The replacement of the elitist middle screens is to replace a series of threads that are made up of luminescent elements in three main colors, evoking vertical smogs. Such a system ensures high image contrast and good color saturation, which at the same time ensures high clarity of monitors with tubes based on the same technology. The mask, which is victorious in Sony handsets, as well as CTX, Mitsubishi, ViewSonic, is thin foil, on which thin vertical lines are cut. Vaughn is trimmed on one (at the great monitors - on dekilkoh) horizontal dart-string, the shadow of which can be seen on the screen. Tsya tyaganina is zastosovuetsya for extinguishing coliving and is called a damping (stabilizing) thread (damper wire).

The minimum distance between two single-colour threads on the screen is called strip pitch. The introduction of a better understanding: "crook of a point", "smooth crop", "croc of smuga" can be related to the broader broader term "grain size", let's look below.

In the yakost color monitors composite color monitors are also used to ensure color, graphics, and ale h to finish with a low distribution of buildings.

RGB-monitors are more illustrative, which may have a high diversity of buildings and graphics and color details, they have their own wires for skin s main color signals (for composite ones - all three color signals pass through one wire).

RGB monitors work at once with a color graphics controller. Three types of video monitors: CD (Color Display), ECD (Enhanced CD) and PGS (Professional Graphics System), set the standard for color monitors for a wide range of applications, but in this hour, only a few of them deserve respect.

Personal computers vicorate for displaying text and graphic images different types display. Below, the classification of the displays is inferred from the interface they have with the computer.

• Composite screen. May have one analog input line. The display can be both colorful and monochrome. The video signal must be connected to the display using the NTSC (National Television System Committee) standard. Tsey standard vikoristovuєtsya also in television. The composite display is installed at once with the CGA video adapter.
• Digital screen. May in one to six input lines. Up to 2n different colors can be displayed on the digital display, de n more number of input lines. Tsey type The display can be switched between EGA and CGA.
• Analog RGB display. Maє three analogue input lines (keruyuchi chervonim, green and blue colors). The value of the tension of the skin line is determined by the intensity of the visible color on the screen. The number of colors that can look like an analog display is actually limited by the capabilities of a video adapter. The analog display is mixed with VGA, Super VGA and XGA.

The parameters of the widest displays that can be installed on computers that are compatible with the IBM PC / XT / AT are shown in the table:

Table 2.1 Display types

1.1. Monochrome display

At first, the IBM PC came with an IBM monochrome display (MD) and a monochrome video adapter (MDA). Although MDA does not allow for the possibility of choosing graphics and different colors, but for the rahunka of a high distribution building - 720x350 The next step for a perfect video system was the creation of Hercules Technology, INC. a new Hercules video adapter (Hercules), which was designed at the same time from a monochrome display from IBM (MD). This adapter is summіsnyy iz MDA and naє koristuvachevі mozhlivіst vikoristannya graphics.

The monochrome display of the IBM company and the sum of the frame rates with it, which is as high as 50 Hz.

1.2. color display

The IBM color display (CD - Color Display) is mixed together with a color graphics adapter (CGA) and provides a choice of colors for graphics and a maximum color for text. The color display itself can display sixteen different colors. The size of the color display is smaller, the lower one for monochrome is 640x200 and the size of the symbols is 8 pixels (a pixel is the smallest element of the image) for the height and 8 pixels for the width. As a result, you can see that the symbols are added up with eight pixels. With the appearance of a painted color display, which may have a great diversity of buildings, which is not enough time to fall asleep.

The color screen can change the frame rate, equal to 60Hz.

1.3. Color display

Improved color display of creations for vikoristnya at once with the EGA video adapter. Vіn mає more razdіlnu zdatnіst - 640x350 and you can choose more number of colors (whether 16 z 64), lower sizable color display. Symbols can be 8 pixels wide and 14 pixels high.

1.4. Rich frequency color display

This display can be used with a different frame rate, which allows you to adjust the modes with a different distribution building. Sound different displays 640x350 (what EGA supports) and more - 640x400, 640x480, 800x600, 1024x768. The remaining two modes are implemented only by Super VGA and XGA video adapters.

The rich frequency color display can display more colors, lower the color display. When working in digital mode, the number of colors can be 64, which is ECD, and when working in analog mode, you can practically change the number of colors. More high-frequency displays can be switched from VGA at once. The first models of NEC's high-frequency screen did not support the VGA video adapter.

1.5. VGA display

For the VGA video adapter by IBM, there is a large scale analog RGB display, as well as a high capacity monochrome analog display. On a monochrome display, different colors are displayed with different gradations of gray colors. Two displays (monochrome and color) and interchangeable - programs written for one of the displays can be used with another display.

The first black-and-white TV set with RK-display appeared in 1976. (Sharp) and mac screen 160×120 pixels. The idea of ​​using similar screens for amateur designs long hour nashtovhuvalsya on a banal problem - too expensive for home sales. In the rest of the years, the situation has fundamentally changed, and monochrome graphic RK-displays GLCD (Graphic Liquid Crystal Display) have become not richly expensive for alphanumeric counterparts.

The advantages of graphical indicators in front of symbolic ones are obvious, even if they allow you to display a two-dimensional raster image on the screen with images that are really visible. The widcodes of current MK are sufficient to display streaming video on a RK display. What is not an analogue of the first black-and-white TV in the intestinal microcontroller version?

Of the impersonal parameters by which to choose GLCD, the type of internal graphics controller is important. There is a system of commands, a physical interface and a software algorithm.

There are close to a dozen different BIS controllers from various manufacturing companies. Similar to the "alphanumeric" RK modules in the GLCD - innovations - controllers can be added to the segment driver. A couple is established, which can be seen as a "chipset", by analogy to motherboards personal computers

For extended GLCDs that are combined with the command system of the KS0108 controller (Samsung), the chipset is indicated through either KS0107/KS0108 or KS0107B/KS0108B. Dosvedcheni retailers know that the name KS0107 is assigned to the segment driver, and KS0108 - to the key controller. Sometimes in the documents they indicate only the type of controller KS0108, but the presence of the driver microcircuit on the other board of the RK display is self-evident.

Rice. Figure 2.43 shows a block diagram of the GLCD KS0107/KS0108 standard with a 128×64 pixel layout. The basis is a matrix of RK-elements, arranged over a width of 128 columns and over a height of 64 rows. To illuminate the skin from 8192 dots of the screen, 192 transistor switches are required, which are found in one KS0107 driver and in two KS0108 controllers. The skin controller has an internal RAM capacity of 4 Kb, as well as the logic of obtaining outbuildings. The driver has its own line of synchronizing signals for the entire system from the RC generator, which is set (details in).

Rice. 2.43. Structural diagram GLCD with organization 128×64 pixels.

Why are there two controller microcircuits in the GLCD, but not one? It is possible to allow, for unification, the shards of the skin from them are shown for their own quadrant 64 × 64 pixels. A proportionally larger number of quadrants can be adjusted whether the screen size is 64×64 to 640×480 pixels.

Graphic RK-displays can be seen as a footwear attribute bright one day screen. Її color determines the body of the picture. For example, black letters on a yellow background. There is no stitched alphabet generator in the display. The programmer is responsible for formulating letters, numbers, symbols, signs. The alphabet can be like that from the world, and there is no need to overdo it.

Unification in the socle and names of contacts, unfortunately, every day you can find y GLCD with one and the same controller. Tse minus, which zmushui is respectful of the data. At Tab. 2.6 for the stock, a collection of signal values ​​is selected, which are recorded in the GLCD, summed from KS0107/KS0108. I especially respect the next name of the display. For example, Winstar WG12864A has a KS0108 controller, and WinstarWG12864D has a T6963C controller, which has a different command system. GLCD is increasing with a decrease in eating +2.4…+3.6 U

Table 2.6. Decryption of GLCD signals according to KS0107/KS0108 standard

The electrical circuits for connecting GLCD to MK are similar one to one, but with different "chipsets" in the middle (Fig. 2.44, a ... g), however software security you will be thoroughly reprimanded. For cheruvannya yaskravistyu pidsvіchuvannya it is possible, by analogy with vikoristovuvat, to look at the earlier scheme from Mal. 2.42, a ... p.

a) a typical connection diagram for the GLCD module, combined with the KS0108 command system. Shinadanih "DB0"…"DB7" is bidirectional. Resistor L2 determines the brightness of the transition. Resistor R1 regulates the contrast between the entire light to dark screen. Negative voltage on the contacts "UEE" -5 ... -8 vibrates in the middle of the GLCD;

b) the type of controller is the same as in Fig. 2.44, a, alepiate and name vysnovkіv GLCD іnші. To regulate the contrast, one constant resistor R1 is sufficient. Yogo opir is indicated by the datasite. Yaskravіst podsvіchuvannya is not regulated;

c) anti-phase signals are sent to the windows CSL, CS2 of the graphic display HG1 (128×64), that is. at the skin moment, the time is spent less than one of two quadrants of pixels (64 × 64). Inverter on transistors VT1 changes the number of lines MK; Pro

About Mal. 2.44. Schemes for connecting graphic RK modules to MK (completed):

d) GLCD HG1 module has an internal controller T6963 from Toshiba. The negative voltage of the contrast ratio control is applied by the resistor R2. Resistor R1 determines the brightness of the signal. Diode VD1 protects the display of the positive voltage applied to the input "Vo" more, lower +0.7;

e) GLCD HG1 module may have an internal controller SED1330 manufactured by Seiko Epson Corp. To adjust the contrast ratio, you need a bipolar life of +5;

f) replacement circuit for the negative voltage GLCD. The contrast is regulated by a changeable resistor R4. Temperature stability is supported by a thermistor RK1. Resistor R3 linearizes the temperature characteristic, which is chosen experimentally;

g) the signal of the cob skid for the display "RES" of the graphic PK-module HG1 is not obv'yazkovo submit to MK. Yogo can be formed with the lantern R1, С/. Transportation - economy of line ports MK.