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67-527: EGA was introduced in October 1984 by IBM, shortly after its new PC/AT . The EGA could be installed in previously released IBM PCs, but required a ROM upgrade on the mainboard . Chips and Technologies ' first product, announced in September 1985, was a four-chip EGA chipset that handled the functions of 19 of IBM's proprietary chips on the original Enhanced Graphics Adapter. By that November's COMDEX , more than

134-469: A anaglyph stereoscopic color scheme, uses the RG color space to simulate a broad spectrum of color in one eye, while the blue portion of the spectrum transmits a black-and-white (black-and-blue) image to the other eye to give depth perception. Here are grouped those full RGB hardware palettes that have the same number of binary levels (i.e., the same number of bits ) for every red, green and blue components using

201-412: A dual-sync design which could switch from the 15.7 kHz of 200-line modes to 21.8 kHz for 350-line modes. Many EGA cards have DIP switches on the back of the card to select the monitor type. If CGA is selected, the card will operate in 200-line mode and use 8×8 characters in text mode . If EGA is selected, the card will operate in 350-line mode and use 8×14 text. Some third-party cards using

268-433: A (2 ) = 32 = 32,768-color palette (commonly known as Highcolor ) as follows: 15-bit systems include: Systems with an 18-bit RGB palette use 6 bits for each of the red, green, and blue color components. This results in a (2 ) = 64 = 262,144-color palette as follows: 18-bit RGB systems include the following: Often known as truecolor and millions of colors , 24-bit color is the highest color depth normally used, and

335-490: A HD read head would only pick up the half track that drive had written, the wider DD read head would pick up the half-track written by the HD drive mixed with the unerased half-track remnant of the track written earlier by a DD drive. Thus, the DD drive would end up reading both new and old information together, causing it to see garbled data. Due to a US antitrust consent decree with IBM,

402-659: A battery-backed real-time clock (RTC) using the Motorola MC146818. This was an improvement from the PC, which required setting the clock manually or installing an RTC expansion card. The RTC also included a 1024 Hz timer (on IRQ 8), a much finer resolution than the 18 Hz timer on the PC. In addition to keeping the time, the RTC includes 50 bytes of CMOS memory which is used to store software-adjustable BIOS parameters. A disk-based BIOS setup program which saved to this memory took

469-660: A byte indicating the result of comparing all four planes can be read on the I/O bus. IBM Personal Computer AT The IBM Personal Computer AT (model 5170, abbreviated as IBM AT or PC/AT ) was released in 1984 as the fourth model in the IBM Personal Computer line, following the IBM PC/XT and its IBM Portable PC variant. It was designed around the Intel 80286 microprocessor . IBM did not specify an expanded form of AT on

536-476: A color from the EGA palette, two bits are used for the red, green and blue channels to signal values of 0, 1, 2 or 3. For instance, to select the color magenta, the red and blue values would be medium intensity (2, or 10 in binary) and the green value would be off (0). The table below displays an example palette matching the standard 16 CGA colors, with their representations in rgbRGB binary (internal card bit order), where

603-540: A comparable computer at COMDEX Las Vegas that year. The AT is IBM PC compatible , with the most significant difference being a move to the 80286 processor from the 8088 processor of prior models. Like the IBM PC, the AT supported an optional math co-processor chip, the Intel 80287 , for faster execution of floating point operations . In addition, it introduced the AT bus , later known as

670-403: A display of up to 16 colors (using a fixed palette , or one selected from a gamut of 64 colors (6-bit RGB) , depending on mode) at several resolutions up to 640 × 350 pixels, as well as two monochrome modes at higher resolutions. EGA cards include a ROM to extend the system BIOS for additional graphics functions, and a custom CRT controller (CRTC) . The IBM EGA CRTC supports all of

737-614: A fairly good job of reducing visible banding of the level changes: A monochrome 4-bit palette is used on: In an 8-bit color palette each pixel's value is represented by 8 bits resulting in a 256-value palette (2 = 256). This is usually the maximum number of grays in ordinary monochrome systems; each image pixel occupies a single memory byte . Most scanners can capture images in 8-bit grayscale, and image file formats like TIFF and JPEG natively support this monochrome palette size. Alpha channels employed for video overlay also use (conceptually) this palette. The gray level indicates

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804-569: A half dozen companies had announced EGA-compatible boards based on C&T's chipset. The first EGA-compatible board was Vega in December 1985, released by Video Seven and using C&T's chipset. The Vega was half the width of the original IBM EGA board. Between 1984 and 1987, several third-party manufacturers produced compatible cards, such as the Autoswitch EGA or Genoa Systems ' Super EGA chipset. Later cards supporting an extended version of

871-527: A hard drive were shipped with a 5-ohm, 50-watt resistor connected on the +12 V line of the hard disk power connector. In normal operation this resistor drew 2.4 amperes (dissipating 28.8 watts), getting fairly hot. In addition to the unreliable hard disk drive, the high-density floppy disk drives turned out to be problematic. Some ATs came with one high-density (HD) disk drive and one double-density (DD) 360 KB drive. High-density floppy diskette media were compatible only with high-density drives. There

938-544: A heavy reliance on dithering to make up for the limits of the technology. In some systems, as Hercules and CGA graphic cards for the IBM PC , a bit value of 1 represents white pixels (light on) and a value of 0 the black ones (light off); others, like the Atari ST and Apple Macintosh with monochrome monitors, a bit value of 0 means a white pixel (no ink) and a value of 1 means a black pixel (dot of ink), which it approximates to

1005-571: A minimum of 64 KB additional RAM, and up to 192 KB if fully populated with the Graphics Memory Module Kit . Without these upgrades, the card would be limited to four colors in 640 × 350 mode. Output was via direct-drive RGB , as with the CGA, but no composite video output was included. MDA and CGA monitors could be driven, as well as newly released enhanced color monitors for use specifically with EGA. EGA-specific monitors used

1072-462: A variable blue tint due to the indeterminate state of the unconnected secondary blue. The IBM 5154 EGA monitor has a special IBM 5153 CGA compatibility mode when operating with CGA sync signals and automatically changes to the CGA pinout to avoid all of the mentioned problems when operating in this mode. The original IBM EGA card includes a feature connector (blue connector J4, see first photo on this page), providing access to two RCA connectors at

1139-561: Is a notable example of a commercial game that runs in 640 × 350 with 16 colors mode. Modern adventure games, like The Crimson Diamond , use freeware tools like the Adventure Game Studio to create games with EGA-style color palettes but with modern features. The original IBM EGA was an 8-bit PC ISA card with 64 KB of onboard RAM . An optional daughter-board (the Graphics Memory Expansion Card ) provided

1206-434: Is available on most modern display systems and software. Its color palette contains (2 ) = 256 = 16,777,216 colors. 24-bit color can be represented with six hexadecimal digits. The complete palette (shown above) needs a squared image of 4,096 pixels wide (48 MB uncompressed), and there is not enough room in this page to show it at full. This can be imagined as 256 stacked squares like the following, every one of them having

1273-500: Is backward-compatible with CGA, allowing EGA monitors to be used on CGA cards and conversely. When operating in EGA modes, pins 2, 6 and 7 are repurposed for EGA's secondary RGB signals (see pinout table below). When operating in 200-line CGA modes, the EGA card is fully backward compatible with a standard IBM CGA monitor; however, third-party monitors had varying compatibility. Third-party monitors sometimes connected pin two to ground internally. When connected to an EGA card, this shorts

1340-524: Is commonly used in web design. The palette is as follows: 12-bit RGB systems include the following: The Allegro library supported in the (legacy) version 4, an emulated 12-bit color mode example code ("ex12bit.c"), using 8-bit indexed color in VGA/SVGA. It used two pixels for each emulated pixel, paired horizontally, and a specifically adapted 256-color palette. One range of the palette was many brightnesses of one primary color (say green), and another range of

1407-515: Is divided into four "planes" (except 640 × 350  × 2, which has one plane), one for each component of the RGBI color space. Each pixel is represented by one bit in each plane. If a bit in the red plane is on, but none of the equivalent bits in the other pages are, a red pixel will appear in that location on screen. If all the other bits for that particular pixel were also on, it would become white, and so forth. Planes are different sizes depending on

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1474-432: Is represented by a series of color patches. When the number of colors is low, a 1-pixel-size version of the palette appears below it, for easily comparing relative palette sizes. Huge palettes are given directly in one-color-per-pixel color patches. For each unique palette, an image color test chart and sample image ( truecolor original follows) rendered with that palette (without dithering ) are given. The test chart shows

1541-433: Is specific to each machine. Therefore, the number of colors that can be simultaneously displayed in a given text or graphic mode might be different. Also, the actual displayed colors are subject to the output format used - PAL or NTSC , composite or component video , etc. - and might be slightly different. For simulated images and specific hardware and alternate methods to produce colors other than RGB (ex: composite), see

1608-406: Is that those palettes have 2 different shades of gray, where n is the number of bits needed to represent a single pixel . Monochrome graphics displays typically have a black background with a white or light gray image, though green and amber monochrome monitors were also common. Such a palette requires only one bit per pixel. Where photo-realism was desired, these early computer systems had

1675-510: The List of 8-bit computer hardware palettes , the List of 16-bit computer hardware palettes and the List of video game console palettes . For various software arrangements and sorts of colors, including other possible full RGB arrangements within 8-bit color depth displays, see the List of software palettes . These palettes only have some shades of gray, from black to white (considered the darkest and lightest "grays", respectively). The general rule

1742-455: The 130-watt XT power supply. According to IBM's documentation, in order to function properly, the AT power supply needed a load of at least 7.0 amperes on the +5 V line and a minimum of 2.5 amperes on its +12 V line. The power supply would fail to start unless these minimum load requirements were met, but the AT motherboard did not provide much load on the +12 V line. To solve this problem, entry-level IBM AT models that did not have

1809-423: The 640 × 350 high-resolution mode, which requires an enhanced EGA monitor, 16 colors can be selected from a palette comprising all combinations of two bits per pixel for red, green and blue. This is four levels of intensity for each primary color and 64 colors overall. The 640 × 200 and 320 × 200 graphics modes provide backward compatibility with CGA software and monitors, but they can use

1876-569: The AT as the best desktop computer when "price is no object" for 1984, describing it as "an innovative, state-of-the-art computer that has the competition gasping for breath". An industry analyst wrote in Computerworld in 1985 that the AT's power was evidence of IBM's belief that personal computers were more important for the company than minicomputers. On April 2, 1987, IBM announced the Personal System/2 (PS/2) line, which they marketed as

1943-552: The AT, originally a Seagate ST506 compatible interface on IBM's disk controller card, was updated and standardized as ATA ("AT Attachment") by Western Digital and Compaq in 1986, and later renamed PATA ( Parallel AT Attachment ). The ATA interface was also known as IDE, because the drive controller, instead of being on the interface card, was integrated into the drive ( Integrated Drive Electronics ). As of January 1985 AT sales were so strong that IBM and its suppliers could not keep up with demand. Creative Computing chose

2010-473: The CGA pin assignment in 200-line modes, so the monitor can also be used with a CGA card. Some EGA monitors are switchable , meaning that they can be set up to use the full palette even in 200-line modes, often through a mechanical switch. Only a few commercial games were released with support for the extended color palette in 320 × 200 or 640 × 200 (including the DOS version of Super Off Road ). When selecting

2077-535: The EGA specification were sold with the full 128 KB of RAM from the factory, while others included as much as 256 KB to enable multiple graphics pages, multiple text-mode character sets , and large scrolling displays. A few third-party cards, such as the ATI Technologies EGA Wonder , built on the EGA standard to additionally offer features such as extended graphics modes as high as 800 × 560 and automatic monitor type detection. EGA produces

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2144-482: The EGA's secondary red output to ground and can damage the card. Also, some monitors were wired with pin two as their sole ground, and these will not work with the EGA. Conversely, an EGA monitor should work with a CGA adapter, but if it is not set to CGA mode, the secondary red signal will be grounded (always zero), and the secondary blue will be floating (unconnected), causing all high-intensity colors except brown to display incorrectly, and all colors to potentially have

2211-450: The EGA, all 16 CGA colors can be used simultaneously, and each can be mapped in from a larger palette of 64 colors (two bits each for red, green and blue). The CGA's alternate brown color is included in the larger palette, so it can be used without any additional display hardware. The later VGA standard built on this by mapping each of the 64 colors in from a larger, customizable, palette of 256. Standard EGA monitors do not support use of

2278-493: The EGA, the video memory begins at address A0000h and occupies 64 KB. The different base addresses for color vs. monochrome modes makes it possible for an EGA to be used simultaneously with a monochrome graphics card in the same computer, or for an EGA in MDA text mode to be used simultaneously with a CGA in the same computer. EGA's native graphics modes are planar , as opposed to the interleaved CGA and Hercules modes. Video memory

2345-602: The IBM PC AT. In the United States, popular brands of AT clones included the Tandy 3000 , Compaq Deskpro 286, HP Vectra, Zenith Z-286, Epson Equity Models II+ and III, and Commodore PC-30 and PC-40 . In Europe, on the other hand, most AT-clones sold were more or less anonymous. The AT bus became the de facto ISA ( Industry Standard Architecture ), while PC XT slots were retroactively named 8-bit ISA . The disk interface for

2412-501: The ISA bus, a 16-bit bus with backward compatibility with 8-bit PC-compatible expansion cards. The bus also offered fifteen IRQs and seven DMA channels, expanded from eight IRQs and four DMA channels for the PC, achieved by adding another 8259A IRQ controller and another 8237A DMA controller. Some IRQ and DMA channels are used by the motherboard and not exposed on the expansion bus. Both dual IRQ and DMA chipsets are cascading which shares

2479-639: The PC AT architecture was functionally an open design, and IBM's efforts to trademark the AT name largely failed. Many 286-based PCs were modeled after it and marketed as AT-compatible . The label also became a standard term in reference to PCs that used the same type of power supply, case, and motherboard layout as the 5170. AT-class became a term describing any machine which supported the same BIOS functions, 80286 or greater processor, 16-bit expansion slots, keyboard interface, 1.2 MB 5 + 1 ⁄ 4 inch floppy disk drives and other defining technical features of

2546-494: The PC keyboard, but a different, bidirectional electrical interface with different keyboard scan codes . The bidirectional interface allows the computer to set the LED indicators on the keyboard, reset the keyboard, set the typematic rate, and other features. Later ATs included 101-key keyboards, e.g. the Model M keyboard . The AT is also equipped with a physical lock that prevents access to

2613-567: The VGA were similarly named Super VGA . The EGA standard was made obsolete in 1987 by the introduction of MCGA and VGA with the PS/2 computer line. Commercial software began supporting EGA soon after its introduction, with The Ancient Art of War , released in 1984. Microsoft Flight Simulator v2.12 , Jet , Silent Service , and Cyrus , all released in 1985, offered EGA support, along with Windows 1.0 . Sierra's King's Quest III , released in 1986,

2680-475: The back of card, in addition to several analog and digital signals that the EGA adaptor can be configured to use. A light pen interface was also present on the original card. For color text and CGA graphics modes, video memory is mapped to 16 KB of addresses beginning at address B8000h, and in monochrome (MDA-compatible) text mode, video memory occupies 16 KB beginning at B0000h. These address mappings are for backward compatibility. For modes new to

2747-425: The colors of any given palette, and the sample image indicates how the color selection of such palettes could represent real-life images. These images are not necessarily representative of how the image would be displayed on the original graphics hardware, as the hardware may have additional limitations regarding the maximum display resolution , pixel aspect ratio and color placement. Implementation of these formats

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2814-460: The computer by disabling the keyboard and holding the system unit's cover in place. ATs could be equipped with CGA , MDA , EGA , or PGA video cards. The 8250 UART from the PC was upgraded to the 16450 , but since both chips had single-byte buffers, high-speed serial communication was problematic as with the XT. The IBM PC AT came with a 192-watt switching power supply , significantly higher than

2881-565: The direct replacement for the AT for customers who wanted to buy a true IBM system. List of monochrome and RGB color formats#6-bit RGB This list of monochrome and RGB palettes includes generic repertoires of colors ( color palettes ) to produce black-and-white and RGB color pictures by a computer's display hardware . RGB is the most common method to produce colors for displays; so these complete RGB color repertoires have every possible combination of R-G-B triplets within any given maximum number of levels per component. Each palette

2948-401: The diskette would be problematic. Conversely, the high-density drive's heads had a track width half that of the 360 KB drive, so they were incapable of fully erasing and overwriting tracks written by a 360 KB drive. Overwriting a DD disk that had been written in a DD drive with an HD drive would result in a disk that read on an HD drive, but produced read errors in a DD drive. Whereas

3015-471: The entire sixteen-color CGA palette simultaneously, instead of the smaller four-color palettes that the actual CGA is limited to in those modes. EGA's 16-color graphic modes use bit planes and mask registers together with CPU bitwise operations for accelerated graphics . The same techniques went on to be used in the VGA . EGA supports: Text modes: Extended graphics modes of third-party boards: With

3082-490: The extended color palette in 200-line modes, because the monitor cannot distinguish between being connected to a CGA card or being connected to an EGA card outputting a 200-line mode. EGA redefines some pins of the connector to carry the extended color information. If the monitor were connected to a CGA card, these pins would not carry valid color information, and the screen might be garbled if the monitor were to interpret them as such. For this reason, standard EGA monitors will use

3149-486: The following: Systems with a 9-bit RGB palette use 3 bits for each of the red, green, and blue color components. This results in a (2 ) = 8 = 512-color palette as follows: 9-bit RGB systems include the following: Systems with a 12-bit RGB palette use 4 bits for each of the red, green, and blue color components. This results in a (2 ) = 16 = 4096-color palette. 12-bit color can be represented with three hexadecimal digits, also known as shorthand hexadecimal form , which

3216-472: The form of the PS/2 Model 30 , the AT did not. Users either had to forgo all their 16-bit ISA expansion cards and switch to the proprietary Micro Channel architecture , or settle for a clone if they wanted to upgrade their machine while keeping their expansions. Eventually, in September 1988, IBM announced the PS/2 Model 30 286 , which featured an Intel 80286 processor and 16-bit ISA expansion slots, serving as

3283-448: The full RGB color model. Thus, the total number of colors are always the number of possible levels by component, n , raised to a power of 3: n × n × n  =  n . 3-bit RGB dithering: Systems with a 3-bit RGB palette use 1 bit for each of the red, green and blue color components. That is, each component is either "on" or "off" with no intermediate states. This results in an 8-color palette ((2 ) = 2 = 8) that has black, white,

3350-410: The full 256 levels of the red, green, and blue (RGB) primary colors and cyan, magenta, and yellow complementary colors, along with a full 256-level grayscale. Gradients of RGB intermediate colors (orange, lime green, sea green, sky blue, violet, and fuchsia), and a full hue spectrum are also present. Color charts are not gamma corrected. These elements illustrate the color depth and distribution of

3417-459: The lowercase letters are the low-intensity bits, and uppercase letters are high-intensity bits. Decimal and hexadecimal values (converted to equivalent 24-bit sRGB web colors ) are also shown. The following images illustrate the full EGA palette in detail. EGA uses a female nine-pin D-subminiature ( DE-9 ) connector for output, identical to the CGA connector. The signal standard and pinout

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3484-564: The machine, press releases, brochures or documentation, but some sources expand the term as Advanced Technology , including at least one internal IBM document. IBM 's 1984 introduction of the AT was seen as an unusual move for the company, which typically waited for competitors to release new products before producing its own models. At $ 4,000–6,000, it was only slightly more expensive than considerably slower IBM models. The announcement surprised rival executives, who admitted that matching IBM's prices would be difficult. No major competitor showed

3551-455: The mode: All planes reside at segment A000 in the CPU's address space. They are bank-switched, and only one plane can be read on the CPU bus at once; however, the programmer may set the control registers on the card to select which planes are written to and write to several at once. An exception is read mode 1, in which all four planes are read and compared with programmed "Color Compare" data, and

3618-720: The modes of the IBM MDA and CGA adapters through specific mode options, but it is not fully register-compatible with the Motorola MC6845 used in those cards, so software that directly programs the registers to select modes may produce different results on the EGA. Supported resolutions are 320 × 200 and 640 × 200 (on a CGA or EGA monitor), 720 × 350 and 640 × 350 (on an MDA monitor) and 320 × 350 and 640 × 350 (on an EGA monitor). EGA scans at 21.8 kHz when 350-line modes are used and 15.7 kHz when 200-line modes are used. In

3685-530: The opacity of the blended image pixel over the background image pixel. The RG or red–green color space is a color space that uses only two primary colors: red and green . It was used on early color processes for films. It was used as an additive format, similar to the RGB color model but without a blue channel, on processes such as Kinemacolor , Prizma , Technicolor I, Raycol , etc., producing shades of black, red, green and yellow. Alternatively, it

3752-430: The other two primaries mixed together at different amounts and brightnesses (red and blue). It effectively reduced the horizontal resolution by half, but allowed a 12-bit "true color" in DOS and other 8-bit VGA/SVGA modes. The effect also somewhat reduced the total brightness of the screen. [REDACTED] Systems with a 15-bit RGB palette use 5 bits for each of the red, green, and blue color components. This results in

3819-639: The place of the DIP switches used to set system settings on PCs. Most AT clones have the setup program in ROM rather than on disk. The standard floppy drive was upgraded to a 1.2 MB 5 + 1 ⁄ 4  inch floppy disk drive (15 sectors of 512 bytes, 80 tracks, two sides), which stored over three times as much data as the 360 KB PC floppy disk, but had compatibility problems with 360k disks (see Problems below). 3 + 1 ⁄ 2  inch floppy drives became available in later ATs. A 20 MB hard disk drive

3886-438: The primary pair. In addition to these chipsets, Intel 82284 Clock Driver and Ready Interface and Intel 82288 Bus Controller are to support the microprocessor. The 24-bit address bus of the 286 expands RAM capacity to 16  MB . PC DOS 3.0 was included with support for the new AT features, including preliminary kernel support for networking (which was fully supported in a later version 3.x release). The motherboard includes

3953-408: The printing logic. In a 2-bit color palette each pixel's value is represented by 2 bits resulting in a 4-value palette (2 = 4). 2-bit dithering: It has black, white and two intermediate levels of gray as follows: A monochrome 2-bit palette is used on: In a 4-bit color palette each pixel's value is represented by 4 bits resulting in a 16-value palette (2 = 16): 4-bit grayscale dithering does

4020-593: The range of luminance , or gray scale, offered in a 30-bit color system would have 1,024 levels of luminance rather than the 256 of the common standard 24-bit, to which the human eye is more sensitive than to hue. This reduces the banding effect for gradients across large areas. These also are full RGB palette repertories, but either they do not have the same number of levels for every red, green and blue components, or they are bit levels based. Nevertheless, all of them are used in very popular personal computers . For further details on color palettes for these systems, see

4087-922: The same given value for the red component, from 0 to 255. The color transitions in these patches must be seen as continuous. If color stepping ( banding ) inside is visible, then probably the display is set to a Highcolor (15- or 16- bits RGB, 32,768 or 65,536 colors) mode or lesser. This is also the number of colors used in true color image files, like Truevision TGA , TIFF , JPEG (the last internally encoded as YCbCr ) and Windows Bitmap , captured with scanners and digital cameras , as well as those created with 3D computer graphics software. 24-bit RGB systems include: Some newer graphics cards support 30-bit RGB and more . Its color palette contains (2 ) = 1024 = 1,073,741,824 colors. However, there are few operating systems or applications that support this mode yet. For some people, it may be hard to distinguish between higher color palettes than 24-bit color offers. However,

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4154-553: The second-generation of IBM PC. The company promised to continue manufacturing certain models of the first-generation PC, including the AT, for the coming months. In June 1987, they announced the full withdrawal of the PC/XT and the imminent discontinuation of the PC/AT. The last units of PC/AT (model 339) rolled off the assembly line in July. While the PC/XT received a directly compatible replacement in

4221-445: The three RGB primary colors red, green and blue and their correspondent complementary colors cyan, magenta and yellow as follows: The color indices vary between implementations; therefore, index numbers are not given. The 3-bit RGB palette is used by: Systems with a 6-bit RGB palette use 2 bits for each of the red, green, and blue color components. This results in a (2 ) = 4 = 64-color palette as follows: 6-bit RGB systems include

4288-460: Was included as standard. Early drives were manufactured by Computer Memories and were found to be very unreliable. The AT included the AT keyboard , initially a new 84-key layout (the 84th key being SysRq ). The numerical keypad was now clearly separated from the main key group, and indicator LEDs were added for Caps Lock, Scroll Lock and Num Lock. The AT keyboard uses the same 5-pin DIN connector as

4355-420: Was no way for the disk drive to detect what kind of floppy disk was inserted, and the drives were not distinguished except by an asterisk molded into the 360 KB disk drive faceplate. If the user accidentally used a high-density diskette in the 360 KB drive, it would sometimes work, for a while, but the high- coercivity oxide would take a very weak magnetization from the 360 KB write heads, so reading

4422-439: Was one of the earliest mainstream PC games to use it. By 1987, EGA support was commonplace. Most software made up to 1991 could run in EGA, although the vast majority of commercial games used 320 × 200 with 16 colors for backward compatibility with CGA and Tandy , and to support users who did not own an enhanced EGA monitor. 350-line modes were mostly used by freeware/shareware games and application software, although SimCity

4489-444: Was used as a subtractive format on Brewster Color I, Kodachrome I , Prizma II, Technicolor II, etc., producing shades of transparent, red, green and black. Until recently, its primary use was in low-cost light-emitting diode displays in which red and green tended to be far more common than the still nascent blue LED technology, but full-color LEDs with blue have become more common in recent years. ColorCode 3-D ,

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