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Enhanced Graphics Adapter

The Enhanced Graphics Adapter is an IBM PC computer display standard from 1984 that superseded and exceeded the capabilities of the CGA standard introduced with the original IBM PC, was itself superseded by the VGA standard in 1987. EGA was introduced in October 1984 by IBM, shortly after its new PC/AT; the EGA standard was made obsolete by the introduction in 1987 of MCGA and VGA with the PS/2 computer line. Shortly before the introduction of VGA, Genoa Systems introduced a half-size graphics card built around a proprietary chip set, which they called Super EGA. Around that time, Byte Magazine reviewed various proprietary enhanced EGA adapters described with the term "EEGA". EGA produces a display of sixteen simultaneous colors from a palette of sixty-four, at a resolution of up to 640×350 pixels; the EGA card includes a 16 KB ROM to extend the system BIOS for additional graphics functions, includes a custom CRT controller that has limited backward compatibility with the Motorola MC6845 chip used to generate video timing signals in earlier IBM PC graphics controllers.

The EGA CRTC can support all of the modes of the IBM MDA and CGA adapters through specific mode options intended for this purpose, but in its maximum-compatibility mode configuration it is not register-compatible with an MC6845, so programs that directly program the 6845 to set up video modes will fail on an EGA. When an MDA or CGA mode is set up on the EGA by calling the BIOS the raster timing, video memory layout, data format, some other low-level hardware details such as cursor control are identical to those aspects of the operation of an MDA or CGA, providing a high degree of direct software and hardware compatibility. In the 640×350 high resolution mode, each of the sixteen colors can be selected from a palette comprising all possible combinations of two bits per pixel each for red and blue, allowing four levels of intensity for each primary color and sixty-four possible colors overall. EGA includes full sixteen-color versions of the CGA 640×200 and 320×200 graphics modes. Depending on the monitor, only the sixteen CGA/RGBI colors are available in these modes.

EGA four-bit graphic modes are notable for a sophisticated use of bit planes and mask registers together with CPU bitwise operations, which constitutes an early graphics accelerator inherited by VGA and numerous compatible hardware design models. EGA is dual-sync; the original CGA modes are present, though EGA is not 100% hardware compatible with CGA, as was mentioned. EGA can drive an MDA monitor by a special setting of switches on the board. In summary, the EGA supports all BIOS-standard video modes of all previous IBM PC video adapters except the enhanced CGA of the IBM PCjr; the standard MDA and CGA modes are supported 100% at the BIOS level, with additional support in some details at the hardware register level. The three enhanced graphics modes of the PCjr—160x200 16-color, 320x200 16-color, 640x200 4-color—are not supported by the EGA, IBM lists their BIOS video mode numbers as reserved. However, the EGA can generate displays equivalent to these modes using different modes; the EGA 320x200 16-color mode is not the same as nor compatible with the PCjr mode of the same format: the PCjr mode uses 4-bit pixels that are packed 2 pixels to a byte in a 32 KB video buffer, split into 4 banks of interleaved lines, whereas the EGA mode uses the linear bit-plane format, native to the EGA.

EGA cards were available starting in both eight - and sixteen-bit versions. The original IBM EGA card had 64 KB of onboard RAM and required a daughter-board to add an additional 64 KB. All third-party cards came with 128 KB installed and some 256 KB, allowing multiple graphics pages, multiple text-mode character sets, large scrolling displays. A few third-party EGA clones feature a range of extended graphics modes, as well as automatic monitor type detection, sometimes a special 400-line interlace mode for use on CGA monitors. EGA supports: 640×350 w/16 colors, pixel aspect ratio of 1:1.37. 640×350 w/2 colors, pixel aspect ratio of 1:1.37. 640×200 w/16 colors, pixel aspect ratio of 1:2.4. 320×200 w/16 colors, pixel aspect ratio of 1:1.2. Text modes: 40×25 with 8×8 pixel font 80×25 with 8×8 pixel font 80×25 with 8×14 pixel font 80×43 with 8×8 pixel font Extended graphics modes of third party boards: 640×400 640×480 720×540 The EGA palette allows all 16 CGA colors to be used and it allows substitution of each of these colors with any one from a total of 64 colors.

This allows the CGA's alternate brown color to be used without any additional display hardware. The VGA standard built on this by allowing each of the 64 colors to be further customized. However, standard EGA monitors do no

Battle of Bi

The Battle of Bi was fought during the Spring and Autumn period in 597 BC, between the major states of Chǔ and Jìn, in what is now modern day China. Occurring three and a half decades after the Battle of Chengpu, where Jin decisively defeated Chu, the battle was a major victory for Chu, cementing the position of its ruler King Zhuang as a hegemon among the states of the Zhou Dynasty; the states of Jin and Chu were both among the most powerful of their time, but while Jin was considered a legitimate Zhou state in terms of culture and lineage, the state of Chu - whose territory encompassed many non-Chinese cultures in the middle Yangtze River - was considered a half-civilised state at best. Jin-Chu rivalry last came to a head with the decisive defeat of Chu at the Battle of Chengpu, where Duke Wen of Jin became hegemon among the states; this situation would change with the death of Zhao Dun in 601 BC, as well as the death of Duke Cheng of Jin the following year, followed by that of Zhao's successor Xi Que in 598 BC.

King Zhuang made use of the resulting instability among the Jin leadership, led a campaign northward. King Zhuang targeted the state of Zheng, an ally of Jin, forced Zheng to switch allegiance to Chu. Meanwhile, Xun Linfu, the new commander of the Jin armies, led his forces to relieve Zheng, only to learn of the surrender of Zheng en route, while camped along the northern bank of the Yellow River; this created a rift about whether to meet the Chu forces in battle. At the same time, Chu's armies decamped, awaiting the Jin offensive. Xun Linfu, after hearing of Zheng's switch of allegiance, was in favour of retreating; this forced the rest of the army to follow suit. Meanwhile, on the Chu side, King Zhuang was intimidated by the presence of the Jin army. Wu Can, a Chu commander, advised against this, citing the inexperience of Xun Linfu as the supreme commander, the rashness of Xian Hu as adjutant, the conflict between the Jin commanders. King Zhuang thus resolved to face down the Jin army though negotiations for a truce continued between the two armies.

The battle began only when two generals from the Jin army, dissatisfied at Xun Linfu's hesitation, decided to provoke the Chu forces. King Zhuang pursued the generals. Fearing that the king could be cut off by the army, Sunshu Ao ordered a general advance from the Chu army. King Zhuang, upon winning the battle, led his generals to water their horses from the Yellow River. Peers, C. J. Ancient Chinese Armies: 1500-200 BC, Osprey Publishing

Ian Chapman (professor)

Professor Ian Chapman is a British physicist, the chief executive of the United Kingdom Atomic Energy Authority. After graduating from Durham University with an M. Sci. in Mathematics and Physics in 2004, Chapman joined UKAEA's Culham laboratory as a plasma physics PhD student with Imperial College London. His research focused on understanding and controlling instabilities in the plasma fuel within tokamak fusion devices, he received his PhD in 2008. Chapman continued his plasma physics research at Culham and progressed through a number of positions in the UK fusion programme, including Head of Tokamak Science in 2014 and Fusion Programme Manager in 2015. In October 2016 he became UKAEA's Chief Executive Officer, he has published over 110 journal papers and given 30 invited lead-author presentations at international conferences. In 2015, he became a visiting professor at Durham University. Chapman has held a number of international roles in fusion research, he was a Task Force Leader for the Joint European Torus fusion device from 2012 to 2014.

He was appointed a member of the programme advisory committee for US experiment NSTX-U in 2013. He has chaired international working groups for the international fusion project ITER and led work packages within the EU fusion programme. Chapman's research has been recognised with a number of notable awards, including: SET For Britain Best Early Career Physicist International Union of Pure and Applied Physics Young Scientist Prize Fellowship of Institute of Physics Institute of Physics Clifford Paterson Medal and Prize European Physical Society Early Career Prize