Editing Hercules Graphics Card (section)

== Use ==
In text mode, the HGC appears exactly like an MDA card.<ref name="wadlow198312">{{cite news |url=https://archive.org/stream/byte-magazine-1983-12/1983_12_BYTE_08-12_Easy_Software#page/n343/mode/2up |title=The Hercules Graphics Card |work=BYTE |date=December 1983 |access-date=2013-10-20 |author-last=Wadlow |author-first=Tom |pages=343}}</ref> Graphics mode requires new techniques to use. Unlike the MDA and CGA, the [[BIOS|PC BIOS]] provides no intrinsic support for the HGC. Hercules developed extensions, called ''HBASIC'', for [[IBM BASIC|IBM Advanced BASIC]] to add HGC support<ref>{{Cite news |last=Wadlow |first=Tom |date=December 1983 |title=The Hercules Graphics Card |pages=343 |work=BYTE Magazine |url=https://www.tech-insider.org/personal-computers/research/acrobat/8312.pdf}}</ref> and Hercules cards came with ''Graph X'', a [[software library]] for Hercules graphical-mode support and [[geometric primitive]]s.{{r|wadlow198312}}

Popular IBM PC programs such as [[Lotus 1-2-3]] spreadsheet,{{r|wadlow198312}} [[AutoCAD]] computer-aided drafting, [[Pagemaker]] and [[Xerox Ventura]] desktop publishing, and [[Microsoft Flight Simulator 2.0]] came with their own drivers to use the Hercules graphics mode.<ref>{{Cite web |date=May 1984 |title=Microsoft Flight Simulator (v2.0) back cover scan |url=https://www.mobygames.com/game/pc-booter/microsoft-flight-simulator-v20/cover-art/gameCoverId,2149/ |website=MobyGames}}</ref>

Though the graphics mode of the Hercules card is not CGA-compatible, it is similar enough to the two CGA graphics modes that with the use of third-party [[terminate-and-stay-resident program]]s it can also work with programs written for the CGA card's standard graphics modes. As the Hercules card does not actually have color-generating circuitry, nor can it connect to a color monitor, color appears as simulated grayscale in varying [[Dither|dithering patterns]].<ref>{{Cite web|title=ibm pc - How do CGA emulators for Hercules graphics work?|url=https://retrocomputing.stackexchange.com/questions/6963/how-do-cga-emulators-for-hercules-graphics-work|access-date=2021-02-07|website=Retrocomputing Stack Exchange}}</ref><ref>{{Cite web |title=CGA Simulators for Hercules Cards |url=https://www.dosdays.co.uk/topics/cga_simulators_for_hercules.php |access-date=2022-12-03 |website=DOS Days - Old PC Computing Resource}}</ref><ref>{{Cite web |last=Guzis |first=C. |date=1987 |title=SIMCGA - A CGA SIMULATOR FOR MONOCHROME GRAPHICS CARDS |url=https://www.pcorner.com/list/GRAPHUTI/SIMCGA41.ZIP/INFO/ |access-date=2022-12-03 |website=The Programmer's Corner |archive-date=2022-12-03 |archive-url=https://web.archive.org/web/20221203150326/https://www.pcorner.com/list/GRAPHUTI/SIMCGA41.ZIP/INFO/ |url-status=dead }}</ref>

[[Clone (computing)|Clones]] of the Hercules appeared, including generic models at very low prices, usually without the printer port. Hercules advertisements implied that use of generic Hercules clones can damage the monitor.<ref name="Byte_Magazine">{{cite news |url=https://archive.org/details/byte-magazine-1985-04-rescan/page/n25|title=Hercules ad from Byte Magazine April 1985|work=Byte Magazine|date=April 1985}}</ref>