Professional Graphics Controller (PGC, often called Professional Graphics Adapter and sometimes Professional Graphics Array) is a

graphics card A graphics card (also called a video card, display card, graphics accelerator, graphics adapter, VGA card/VGA, video adapter, display adapter, or colloquially GPU) is a computer expansion card that generates a feed of graphics output to a displa ...

manufactured by

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

for PCs. It consists of three interconnected PCBs, and contains its own processor and memory. The PGC was, at the time of its release, the most advanced graphics card for the IBM XT and aimed for tasks such as CAD. Introduced in 1984, the Professional Graphics Controller offered a maximum resolution of 640 × 480 with 256 colors on an analog

RGB The RGB color model is an additive color model in which the red, green, and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three ...

monitor Monitor or monitor may refer to: Places * Monitor, Alberta * Monitor, Indiana, town in the United States * Monitor, Kentucky * Monitor, Oregon, unincorporated community in the United States * Monitor, Washington * Monitor, Logan County, Wes ...

, at a

refresh rate The refresh rate, also known as vertical refresh rate, vertical scan rate or vertical frequency in reference to terminology originating with the cathode-ray tubes (CRTs), is the number of times per second that a raster-based display device displa ...

of 60 hertz—a higher resolution and color depth than CGA and EGA supported. This mode is not

BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is a type of firmware used to provide runtime services for operating systems and programs and to perform hardware initialization d ...

-supported. It was intended for the

computer-aided design Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve c ...

market and included 320 KB of display

RAM Ram, ram, or RAM most commonly refers to: * A male sheep * Random-access memory, computer memory * Ram Trucks, US, since 2009 ** List of vehicles named Dodge Ram, trucks and vans ** Ram Pickup, produced by Ram Trucks Ram, ram, or RAM may also ref ...

and an on-board

Intel 8088 The Intel 8088 ("''eighty-eighty-eight''", also called iAPX 88) microprocessor is a variant of the Intel 8086. Introduced on June 1, 1979, the 8088 has an eight-bit external data bus instead of the 16-bit bus of the 8086. The 16-bit registers a ...

microprocessor. The 8088 ran software routines such as "draw polygon" and "fill area" from an on-board 64 KB

ROM Rom, or ROM may refer to: Biomechanics and medicine * Risk of mortality, a medical classification to estimate the likelihood of death for a patient * Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac * ...

so that the host

CPU A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary processor in a given computer. Its electronic circuitry executes instructions of a computer program, such as arithmetic, log ...

didn't need to load and run these routines itself. While never widespread in consumer-class personal computers, its list price, plus $1,295 display, compared favorably to US$50,000 dedicated CAD

workstation A workstation is a special computer designed for technical or computational science, scientific applications. Intended primarily to be used by a single user, they are commonly connected to a local area network and run multi-user operating syste ...

s of the time (even when the $4,995 price of a PC XT Model 87 was included). It was discontinued in 1987 with the arrival of

VGA Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. T ...

and 8514.

Software support

The board was targeted at the CAD market, therefore limited software support is to be expected. The only software systems known to support the PGC are IBM's ''

Graphical Kernel System The Graphical Kernel System (GKS) is a 2D computer graphics system using vector graphics, introduced in 1977. It was suitable for making line and bar charts and similar tasks. A key concept was cross-system portability, based on an underlying coo ...

'', ''

P-CAD P-CAD was the brand name of Personal CAD Systems, Inc., a California-based manufacturer of electronic design automation (EDA) software. It manufactured a CAD software available for personal computers. The company was divested into ACCEL Techno ...

4.5'', Canyon State Systems ''CompuShow'' and ''

AutoCAD AutoCAD is a 2D and 3D computer-aided design (CAD) software application developed by Autodesk. It was first released in December 1982 for the CP/M and IBM PC platforms as a desktop app running on microcomputers with internal graphics control ...

2.5''.

Output capabilities

PGC supports: * with 256 colors from a palette of 4,096 ( 12-bit RGB palette, or 4 bits per color component). *

Color Graphics Adapter The Color Graphics Adapter (CGA), originally also called the ''Color/Graphics Adapter'' or ''IBM Color/Graphics Monitor Adapter'', introduced in 1981, was IBM's first color graphics card for the IBM PC and established a De facto standard, de fac ...

text and graphics modes. Text modes use a font with 8×16-pixel character cells and have 400 rows of pixels. There are six possible color arrangements: * Default 256-colour palette - Low 4 bits intensity, high 4 bits colour; * 16-colour palette - Makes the PGC behave as two 16-colour planes. If high 4 bits are 0, low 4 bits are colour; otherwise, high 4 bits are colour; * 2-3-3 palette (Palette 2) - Bits 6-7 red, bits 3-5 green, bits 0-2 blue; * 3-2-3 palette (Palette 3) - Bits 5-7 red, bits 3-4 green, bits 0-2 blue; * 3-3-2 palette (Palette 4) - Bits 5-7 red, bits 2-4 green; bits 0-1 blue; * 6x6x6 colour cube - six equally spaced shades of red, green, and blue.

Operation

The display adapter was composed of three physical circuit boards (one with the on-board microprocessor,

firmware In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, h ...

ROMs and video output connector, one providing CGA emulation, and the third mostly carrying RAM) and occupied two adjacent expansion slots on the XT or AT

motherboard A motherboard, also called a mainboard, a system board, a logic board, and informally a mobo (see #Nomenclature, "Nomenclature" section), is the main printed circuit board (PCB) in general-purpose computers and other expandable systems. It ho ...

or the Expansion Unit; the third card was located in between the two slots. The PGC could not be used in the original IBM PC without the 5161 Expansion Unit due to the different spacing of its slots. In addition to its native mode, the PGC optionally supported the documented text and graphics modes of the

, which could be enabled using an onboard jumper. However, it was only partly

register Register or registration may refer to: Arts, entertainment, and media Music * Register (music), the relative "height" or range of a note, melody, part, instrument, etc. * ''Register'', a 2017 album by Travis Miller * Registration (organ), ...

-compatible with CGA.

Related monitor

The PGC's matching display was the IBM 5175, an analog RGB monitor that is unique to it and not compatible with any other video card without modification. With hardware modification, the 5175 can be used with

Macintosh Mac is a brand of personal computers designed and marketed by Apple Inc., Apple since 1984. The name is short for Macintosh (its official name until 1999), a reference to the McIntosh (apple), McIntosh apple. The current product lineup inclu ...

, and various other analog

video sources. Some surplus 5175s in VGA-converted form were still sold by catalog retailers such as COMB (Close Out Merchant Buyers) as late as the early 1990s.

Hardware clones

Matrox Matrox Graphics, Inc. is a producer of graphics card, video card components and equipment for personal computers and workstations. Based in Dorval, Quebec, Canada, it was founded in 1976 by Lorne Trottier and Branko Matić. The name is derived ...

PG-640, PG-1280 and QG-640 (for the DEC

MicroVAX The MicroVAX is a discontinued family of low-cost minicomputers developed and manufactured by Digital Equipment Corporation (DEC). The first model, the MicroVAX I, shipped in 1984. The series uses processors that implement the VAX instruction se ...

) *

Dell Dell Inc. is an American technology company that develops, sells, repairs, and supports personal computers (PCs), Server (computing), servers, data storage devices, network switches, software, computer peripherals including printers and webcam ...

NEC MVA-1024 card * Everex EPGA * Orchid Technology TurboPGA *Vermont Microsystems IM-640, IM-1024

References

;Notes *Mueller, Scott (1992) ''Upgrading and Repairing PCs, Second Edition'', Que Books, - which says 3 slots and "adapter"
A Professional Graphics Controller
by K. A. Duke and W. A. Wall, IBM Systems Journal

External links

{{IBM personal computers Graphics cards Display technology IBM video hardware