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69-537: 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

138-412: 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

207-429: A transparent color, in order to perform a simple video overlay : superimposing a given image over a background in such way that some part of the overlapped image obscures the background and the remaining not. Superimposing film/TV titles and credits is a typical application of video overlay. In the image to be superimposed (indexed color is assumed), a given palette entry plays the role of the transparent color. Usually

276-474: A CLUT are called indexed color images. As of 2019, the most common image colorspace in graphics cards is the RGB color model with 8 bits per pixel color depth . Using this technique, 8 bits per pixel are used to describe the luminance level in each of the RGB channels , therefore 24 bits fully describe the color of each pixel. The full system palette for such hardware therefore has 2 colors. The objective of

345-496: 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,

414-673: 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

483-681: 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

552-399: A certain color space 's color reproduction range are assigned an index, by which they can be referenced. By referencing the colors via an index, which takes less information than needed to describe the actual colors in the color space, this technique aims to reduce data usage, including processing, transfer bandwidth, RAM usage, and storage. Images in which colors are indicated by references to

621-479: 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

690-550: 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

759-403: 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

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828-581: 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

897-527: 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

966-531: A limited 8-bit depth graphic display, it is necessary to load a given image's adaptive palette into the color hardware registers prior to loading the image surface itself into the frame buffer . To display different images with different adaptive palettes, they must be loaded one by one, as in a slideshow . Here are samples of four different indexed color images with color patches to show their respective (and largely incompatible) adaptive palettes: A single palette entry in an indexed color image can be designated as

1035-585: 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

1104-462: 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

1173-582: 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

1242-500: 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

1311-519: 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

1380-480: Is not being used to hold any translucency data and is set to zero. By contrast, PNG supports alpha channels in palette entries, enabling semi-transparency in paletted images. When dealing with truecolor images, some video mixing equipment can employ the RGB triplet (0,0,0) (no red, no green, no blue: the darkest shade of black, sometimes referred as superblack in this context) as the transparent color. At design time, it

1449-497: Is placed anywhere over the background image, and it is blended in such way that if the pixel color index is the transparent color, the background pixel is kept, otherwise it is replaced. This technique is used for pointers, in typical 2-D videogames for characters, bullets and so on (the sprites ), video titling and other image mixing applications. Some early computers, as Commodore 64 , MSX and Amiga supports sprites and/or full screen video overlay by hardware. In these cases,

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1518-404: Is replaced by the so-called magic pink . The same way, typical desktop publishing software can assume pure white, RGB triplet (255,255,255) from photos and illustrations to be excluded in order to let the text paragraphs to invade the image's bounding box for irregular text arrangement around the image's subjects. 2-D painting programs , like Microsoft Paint and Deluxe Paint , can employ

1587-421: Is sometimes referred to as a uniform palette . The normal human eye has sensibility to the three primary colors in different degrees: the more to the green, the less to the blue. So RGB arrangements can take advantage of this by assigning more levels for the green component and fewer to the blue. A master palette built this way can be filled with up to 8R×8G×4B = 256 colors , but this does not leave space in

1656-560: The Win32 API . The applicability of palettes in Highcolor and Truecolor display modes becomes questionable. These APIs deals with the so-called "system palette" and with many "logical palettes". The "system palette" is a copy in RAM of the color display's hardware registers, primarily a physical palette, and it is a unique, shared common resource of the system. At boot, it is loaded with

1725-529: The default system palette (mainly a "master palette" which works well enough with most programs). When a given application intends to output colorized graphics and/or images, it can set their own "logical palette", that is, its own private selection of colors (up to 256). It is supposed that every graphic element that the application tries to show on screen employs the colors of its logical palette. Every program can manage freely one or more logical palettes without further expected interference (in advance). Before

1794-437: The truecolor original one by using adaptive palettes (sometimes termed adaptative palettes ), in which the colors are selected or quantized through some algorithm directly from the original image (by picking the most frequent colors). This way, and with further dithering , the indexed color image can nearly match the original. But this creates a heavy dependence between the image pixels and its adaptive palette. Assuming

1863-455: 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

1932-423: 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

2001-584: 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

2070-552: 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

2139-476: 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

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2208-546: 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

2277-482: 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

2346-450: 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

2415-496: 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

2484-618: 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

2553-504: 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

2622-643: 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

2691-501: 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

2760-574: 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,

2829-475: 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

Enhanced Graphics Adapter - Misplaced Pages Continue

2898-463: 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

2967-418: The direct replacement for the AT for customers who wanted to buy a true IBM system. Palette (computing) In computer graphics , a palette is the set of available colors from which an image can be made. In some systems, the palette is fixed by the hardware design, and in others it is dynamic, typically implemented via a color lookup table (CLUT), a correspondence table in which selected colors from

3036-401: 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

3105-474: 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

3174-490: 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

3243-537: The fact that many programs fail to handle this event, and their windows will become corrupt in this situation. An application can force the system palette to be loaded with specific colors (even in a specific order), "tricking" the system by telling it they are color entries intended for animation (quick color changes of the colors in the physical palette at specific entries). The system will then assume that those hardware palette entries no longer are free for its palette color management algorithm. The final result depends on

3312-478: 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

3381-404: The index number 0, but other may be chosen if the overlay is performed by software . At design time, the transparent color palette entry is assigned to an arbitrary (usually distinctive) color. In the example below, a typical arrow pointer for a pointing device is designed over an orange background, so here the orange areas denoted the transparent areas (left). At runtime , the overlapped image

3450-409: The least-used color in the system palette (generally, one used by another window in the background) and substitutes it with the new color. Due to there being limited room for colors in the system palette, the algorithm also tries to remap similar colors together and will always avoid creating redundant colors. The final result depends on how many applications are trying to show their colors on screen at

3519-466: 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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3588-564: 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

3657-454: The master palette (after dumping this into the hardware color registers), and writes the result in the video buffer. Here is a sample of a simple mosaic of the four image thumbnails using a master palette of 240 RGB arranged colors plus 16 additional intermediate shades of gray; all images are put together without a significant loss of color accuracy: When using indexed color techniques, real life images are represented with better fidelity to

3726-458: 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

3795-732: 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

3864-406: The output is effectively made, the program must realize its logical palette: The system tries to match the "logical" colors with "physical" ones. If an intended color is already present in the system palette, the system internally maps the logical to the system palette indexes (because they rarely coincide). If the intended color is not present yet, the system applies an internal algorithm to discard

3933-482: The palette for reserved colors, color indices that the program could use for special purposes. It is more general to use only 6R×6G×6B = 216 (as in the Web colors case), 6R×8G×5B = 240 or 6R×7G×6B = 252 , which leaves room for some reserved colors. Then, when loading the mosaic of image thumbnails (or other heterogeneous images), the program simply maps every original indexed color pixel to its most approximated in

4002-645: 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

4071-438: 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

4140-427: The same time in the hardware color registers. A solution is to use a unique, common master palette or universal palette , which can be used to display with reasonable accuracy any kind of image. This is done by selecting colors in such way that the master palette comprises a full RGB color space "in miniature", limiting the possible levels that the red, green, and blue components may have. This kind of arrangement

4209-405: The same time. The foreground window is always favored, so background windows may behave in different ways: from become corrupted to quickly redraw themselves. When the system palette changes, the system triggers a specific event to inform every application. When received, a window can quickly redraw itself using a single Win32 API function. But this must be done explicitly in the program code; hence

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4278-565: 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

4347-412: The transparent palette entry number is defined by the hardware, and it used to be the number 0. Some indexed color image file formats as GIF natively support the designation of a given palette entry as transparent , freely selectable among any of the palette entries used for a given image. The BMP file format reserves space for Alpha channel values in its Color Table, however currently this space

4416-525: The usage of smaller palettes via CLUTs is to lower the number of bits per pixel by reducing the set of possible colors that are to be handled at once (often using adaptive methods). Each possible color is assigned an index, which allows each color to be referenced using less information than needed to fully describe the color. An example is the 256-color palette commonly used in the GIF file format, in which 256 colors to be used to represent an image are selected from

4485-485: The user designated background color as the transparent color when performing cut, copy, and paste operations. Although related (due to they are used for the same purposes), image bit masks and alpha channels are techniques which do not involve the use of palettes nor transparent color at all, but off-image added extra binary data layers. Microsoft Windows applications manage the palette of 4-bit or 8-bit indexed color display devices through specialized functions of

4554-457: The whole 24 bit color space, each being assigned an 8 bit index. This way, while the system can potentially reproduce any color in the RGB color space (as long as the 256 color restriction allows), the storage requirement per pixel is lowered from 24 to 8 bits per pixel. In an application showing many different image thumbnails in a mosaic on screen, the program may not be able to load all the adaptive palettes of every displayed image thumbnail at

4623-463: 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

4692-420: 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

4761-439: 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

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