80 lines
4.8 KiB
Markdown
80 lines
4.8 KiB
Markdown
---
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layout: page
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title: COMPAQ Video Graphics Controller (VGA)
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permalink: /devices/pcx86/video/compaq/vga/
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---
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COMPAQ Video Graphics Controller (VGA)
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---
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This is the COMPAQ Video Graphics Controller Board, one of the earliest VGA boards COMPAQ released
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for its DeskPro 386 line.
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[<img src="https://s3-us-west-2.amazonaws.com/archive.pcjs.org/devices/pcx86/video/compaq/vga/109360-001/Compaq_VGA_109360-001-640.jpg" alt="COMPAQ VGA Board"/>](https://s3-us-west-2.amazonaws.com/archive.pcjs.org/devices/pcx86/video/compaq/vga/109360-001/Compaq_VGA_109360-001.jpg)
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It was featured in the February 16, 1988 of PC Magazine (p.188). At that time, it retailed for $599, and it was described
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as "the sharpest, fastest IBM-standard video board you can slide into your PC." The article goes on to say:
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> The Compaq [Video Graphics Controller Board] is the first truly hardware-compatible VGA board with
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register-level support for all 17 video modes. It's also the first video board from a major manufacturer
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that uses a full 16-bit interface....
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> Per the VGA standard, Compaq's board offers 640- by 480-pixel all-points-addressable graphics resolution
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in 16 colors, as well as 256 colors from a palette of 262,144 at 320- by 200-pixel resolution.
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> Based on a Paradise Systems VLSI VGA chip and an Inmos DAC, the board includes 256K RAM soldered to it.
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Relying on surface-mounted components for just about everything except its BIOS and the aforementioned chips,
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the entire board is just 9 inches long and XT height. Although it will function in an 8-bit expansion slot,
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it achieves its top speed only when its 16-bit interface is put into play.
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> The card-retaining bracket of the board holds only the female DB-15 of the IBM VGA system. This connector,
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coupled with the analog output of the board, means that the [board] will function only with VGA-style monitors.
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> An extra edge connector at the top of the board matches the video expansion available on the IBM PS/2
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Display Adapter card, electrically but not physically compatible with the VGA Feature Connector of PS/2
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computers.
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> To your system, the board looks like an EGA adapter--that is, you run the appropriate setup procedure for
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setting CMOS memory as if it were an EGA card. The two jumpers on the board (its only hardware adjustments)
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alter its base address for matchng unusual systems and ordinarily require no change.
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> In testing, the Compaq Board proved itself functionally compatible with the IBM PS/2 Display Adapter but
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faster, because of its 16-bit interface. On an ordinary AT, it nearly achieved the display speeds of the
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internal VGA system of a stock PS/2 (which has a clock speed advantage over the AT).
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> Although Compaq claims that this board is designed specifically for its own machines, particularly the
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DeskPro 386/20, it works great with non-Compaq machines as well. In fact, with this board, Compaq gives you
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a way of getting the sharpest and fastest graphics without abandoning your commitment to the PC standard.
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As such, this board is in perfect accord with the Compaq philosophy, and it may be the best way available
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for mating a VGA-style monitor and VGA graphics to your AT.
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A copy of the board's [VGA ROM BIOS](109360-001/1988-05-18.json) was created by [dumping](/devices/pcx86/rom/compaq/deskpro386/#dumping-the-roms)
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the contents of each EPROM chip to a *.hex* file, and then merging the *.hex* files with the following
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[FileDump](/modules/filedump/) command:
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cd 109360-001
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filedump --file=109793-002.hex --merge=109794-002.hex --output=1988-05-18.json
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For a more human-readable dump, use the `--comments` option:
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filedump --file=109793-002.hex --merge=109794-002.hex --output=1988-05-18.dump --comments
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And for those who want a binary file, the FileDump API can be used to recreate binary data from JSON data:
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> [http://localhost:8088/api/v1/dump?file=/devices/pcx86/video/compaq/vga/109360-001/1988-05-18.json&format=rom](http://localhost:8088/api/v1/dump?file=/devices/pcx86/video/compaq/vga/109360-001/1988-05-18.json&format=rom)
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The COMPAQ VGA ROM BIOS concludes with the usual copyright string and author initials:
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Copyright COMPAQ Computer Corporation, 1982, 1983, 1984, 1985, 1986, 1987, 1988
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RWS*PNA*NPB*DJC*CAB*ALL*
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V4C 05COMPAQ
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05/18/88
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Four of the authors -- **RWS**, **NPB**, **DJC**, and **CAB** -- are also listed as authors of the
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[DeskPro 386 ROM BIOS](/devices/pcx86/rom/compaq/deskpro386/).
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An older version of the VGA ROM BIOS, [1987-10-27.json](109360-001/1987-10-27.json), is also available online. It comes
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from an [earlier revision](http://bitsavers.trailing-edge.com/pdf/compaq/firmware/109360-001_VGA/) of the same board, with
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the same part number (109360-001).
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cd 109360-001
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filedump --file=http://bitsavers.trailing-edge.com/pdf/compaq/firmware/109360-001_VGA/109328-002.BIN --merge=http://bitsavers.trailing-edge.com/pdf/compaq/firmware/109360-001_VGA/109327-002.BIN --output=1987-10-27.json
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