Multicolor Graphics Adapter
Encyclopedia
The Multi-Color Graphics Array was a video subsystem built into the motherboard of the IBM PS/2 Model 30, introduced on April 2, 1987, and Model 25, introduced later on August 11; no standalone MCGA cards were ever made. The MCGA supported all CGA
display modes plus 640×480 monochrome, 60 Hz refresh rate, and 320×200, 256 colors (out of a palette of 262,144) at 70 Hz refresh rate. The display adapter used a 15-pin D-shell connector. Monochrome text modes compatible with the IBM 5151
monitor were not supported.
MCGA was similar to VGA in that it had a 256-color mode (the 256-color mode in VGA was sometimes referred to as MCGA even though MCGA only existed on a small number of PS/2 models) and used 15-pin analog connectors, but the chipset's abilities were limited to that. MCGA lacked EGA
compatibility, while VGA, on the other hand, was almost fully backward compatible
with EGA. VGA also included other high-resolution display modes.
The 256-color mode proved most popular for gaming, but at the time the MCGA was introduced, many games lacking support for 256-color graphics were forced to fall back to four-color CGA mode (or not run at all) instead of using EGA video modes (320×200 16 colors). Fortunately, many other 16-color EGA games (such as older adventure games from Sierra On-line and Lucasfilm Games) specifically supported MCGA in its 320×200 256-color mode, picking the colors most resembling the 16-color RGB palette, while leaving the other available colors in that mode unused. 256-color VGA games ran fine on MCGA as long as they stuck to the basic 320×200 256-color mode and didn't attempt to use VGA-specific features such as multiple screen pages.
The tenure of MCGA was brief; the PS/2 Model 25 and Model 30 (which had an MCGA display adapter integrated into the motherboard) were discontinued by 1992 and no manufacturer produced a clone of this display adapter, since the VGA standard introduced at the same time was considered superior. MCGA was also rendered redundant to VGA since almost all the capabilities of MCGA were also part of VGA.
The help on screen modes for QuickBASIC
4.5 has some references to the MCGA adapter.
Color Graphics Adapter
The Color Graphics Adapter , originally also called the Color/Graphics Adapter or IBM Color/Graphics Monitor Adapter, introduced in 1981, was IBM's first color graphics card, and the first color computer display standard for the IBM PC....
display modes plus 640×480 monochrome, 60 Hz refresh rate, and 320×200, 256 colors (out of a palette of 262,144) at 70 Hz refresh rate. The display adapter used a 15-pin D-shell connector. Monochrome text modes compatible with the IBM 5151
IBM 5151
The IBM 5151 was 12" transistor–transistor logic monochrome monitor, shipped with the original IBM Personal Computer.It only produced green colors because it used P39 phosphor. IBM designed its MDA monochrome display system to deliver extremely well-formed characters for the time...
monitor were not supported.
MCGA was similar to VGA in that it had a 256-color mode (the 256-color mode in VGA was sometimes referred to as MCGA even though MCGA only existed on a small number of PS/2 models) and used 15-pin analog connectors, but the chipset's abilities were limited to that. MCGA lacked EGA
Enhanced Graphics Adapter
The Enhanced Graphics Adapter is the IBM PC computer display standard specification which is between CGA and VGA in terms of color and space resolution. Introduced in October 1984 by IBM shortly after its new PC/AT, EGA produces a display of 16 simultaneous colors from a palette of 64 at a...
compatibility, while VGA, on the other hand, was almost fully backward compatible
Backward compatibility
In the context of telecommunications and computing, a device or technology is said to be backward or downward compatible if it can work with input generated by an older device...
with EGA. VGA also included other high-resolution display modes.
The 256-color mode proved most popular for gaming, but at the time the MCGA was introduced, many games lacking support for 256-color graphics were forced to fall back to four-color CGA mode (or not run at all) instead of using EGA video modes (320×200 16 colors). Fortunately, many other 16-color EGA games (such as older adventure games from Sierra On-line and Lucasfilm Games) specifically supported MCGA in its 320×200 256-color mode, picking the colors most resembling the 16-color RGB palette, while leaving the other available colors in that mode unused. 256-color VGA games ran fine on MCGA as long as they stuck to the basic 320×200 256-color mode and didn't attempt to use VGA-specific features such as multiple screen pages.
The tenure of MCGA was brief; the PS/2 Model 25 and Model 30 (which had an MCGA display adapter integrated into the motherboard) were discontinued by 1992 and no manufacturer produced a clone of this display adapter, since the VGA standard introduced at the same time was considered superior. MCGA was also rendered redundant to VGA since almost all the capabilities of MCGA were also part of VGA.
The help on screen modes for QuickBASIC
QuickBASIC
Microsoft QuickBASIC is an Integrated Development Environment and compiler for the BASIC programming language that was developed by Microsoft. QuickBASIC runs mainly on DOS, though there was a short-lived version for Mac OS...
4.5 has some references to the MCGA adapter.