Neville Super Freak



Join Date: Apr 2008 Location: Lerida, Spain Posts: 153

CGA, Hercules, EGA and other older display modes explained







Therefore, if today we deal with old games we may be given several obscure (for some people, at least) options to choose from.



CGA - From 1981. Allows up to 320x200 in resolution with 4 simultaneous colors or 620x200 in B/W. Believe it or not, this was an upgrade from the original MDA text-only mode that's rarely seen in games.



CGA is often criticised because of its lack of color variety. In the 320x200 modes only two palettes are available: either red, green, yellow and white, or cyan (pale blue), magenta, black and white. The motives behind this were both economical (the card only needs 16 Kb. RAM to work) and corporative, because IBM favored their office customers over the gaming community.



Hercules - From 1982 onwards. It can show graphics up to 720x350, but only in B/W. Developed by an external company, it tried to combine the main virtues of MDA (its text mode, better than CGA's) and CGA (its highest resolution, two color graphic mode) for a lower cost. It could use B/W, green and orange monitors and it was likely the best option for them.



With the help of a CGA software emulator, it could also display regular CGA modes, but always without colors.



EGA - From 1984. 64 Kb. RAM. Up to 640×350 in resolution and 16 simultaneous colors. CGA compatible.



MCGA - From 1987. Only available in some IBM PS/2 models. Has some 256 color modes available. It's CGA compatible, but not EGA compatible.



VGA - From 1988. 256 Kb. RAM. Up to 800x600x256 colors. Is compatible with previous display modes CGA and EGA (official modes only), but not with Hercules. Trying to show Hercules graphics in a VGA card will result in CGA graphics.



The most used graphic mode (320x200 and 256 colors) is common to MCGA, so some games refer to these graphics as MCGA/VGA.



SVGA - From 1989. Up to 1024x768 and 64k colors. Manufacturers didn't agree on the exact specs, and the VESA standard was later created as a solution. That's why some programs require a VESA compatible video driver in order to work.



Then there are the IBM PCjr. and Tandy 1000. These aren't graphic modes, but two PC models using a CGA card with some extra 16 color modes thrown in. Regular PCs can't access these modes.



More info on them available at:



Code: https://en.wikipedia.org/wiki/IBM_PCjr Code: https://en.wikipedia.org/wiki/Tandy_1000



Now let's see and old game, "Prince of Persia" from 1989, running in different modes:







CGA mode, using a 320x200 resolution and its second palette: cyan, magenta, black and white.









Hercules mode: a higher resolution, which results in sharper graphics, but in B/W only.









This is what we get in a PC with an EGA card or a PCjr. / Tandy computer.









And finally, the same game with VGA and newer cards. PCs started as business machines, and only later were introduced into homes or considered as capable videogame machines. Therefore, it shouldn't be a surprise that their graphical abilities were much behind other computers of its time, such as the Apple II, the Atari ST or the CBM Amiga. It was later, thanks to different hardware upgrades, that PCs became what we know today.Therefore, if today we deal with old games we may be given several obscure (for some people, at least) options to choose from.- From 1981. Allows up to 320x200 in resolution with 4 simultaneous colors or 620x200 in B/W. Believe it or not, this was an upgrade from the originaltext-only mode that's rarely seen in games.is often criticised because of its lack of color variety. In the 320x200 modes only two palettes are available: either red, green, yellow and white, or cyan (pale blue), magenta, black and white. The motives behind this were both economical (the card only needs 16 Kb. RAM to work) and corporative, because IBM favored their office customers over the gaming community.- From 1982 onwards. It can show graphics up to 720x350, but only in B/W. Developed by an external company, it tried to combine the main virtues of MDA (its text mode, better than CGA's) and CGA (its highest resolution, two color graphic mode) for a lower cost. It could use B/W, green and orange monitors and it was likely the best option for them.With the help of a CGA software emulator, it could also display regular CGA modes, but always without colors.- From 1984. 64 Kb. RAM. Up to 640×350 in resolution and 16 simultaneous colors. CGA compatible.- From 1987. Only available in some IBM PS/2 models. Has some 256 color modes available. It's CGA compatible, but not EGA compatible.- From 1988. 256 Kb. RAM. Up to 800x600x256 colors. Is compatible with previous display modes CGA and EGA (official modes only), but not with Hercules. Trying to show Hercules graphics in a VGA card will result in CGA graphics.The most used graphic mode (320x200 and 256 colors) is common to, so some games refer to these graphics as- From 1989. Up to 1024x768 and 64k colors. Manufacturers didn't agree on the exact specs, and the VESA standard was later created as a solution. That's why some programs require a VESA compatible video driver in order to work.Then there are theand. These aren't graphic modes, but two PC models using a CGA card with some extra 16 color modes thrown in.More info on them available at:A few pre-1990 games can be set up under DOSBox or PCem to run into PCjr. / Tandy modes, such as "Arcticfox", "Marble Madness" or "Ninja". This has the advantage of showing 16 colors and 3-channel music and FX.Now let's see and old game, "Prince of Persia" from 1989, running in different modes:CGA mode, using a 320x200 resolution and its second palette: cyan, magenta, black and white.Hercules mode: a higher resolution, which results in sharper graphics, but in B/W only.This is what we get in a PC with an EGA card or a PCjr. / Tandy computer.And finally, the same game with VGA and newer cards. Last edited by Neville; 09-09-2020 at 02:11 PM .