VGATEST

Simple DOS program used to test VGA functionality in both text and graphics modes.

It can be compiled with Open Watcom and needs the DOS/4GW extender.

Source code at https://github.com/barotto/VGATEST

!!! Disclaimer !!!

This program can and will damage the computer that you'll use it on and all of its attached peripherals. The author(s) cannot be held responsible for any damage occurred by the use of this program. Use at your own risk!

Alphanumeric (A/N) tests

Font Maps demo

This demo shows the double font map capability of the VGA that can be used to display 512 different characters on screen. Font map 0 is the default BIOS map. Font map 1 is a 8 pixels wide BIOS map loaded with INT 10/AX=11--h Font maps 2-7 are custom maps.

Keys: 0 to 7 = change Map A's font. ESC = exit

Split & Pan demo

This demo shows the split screen and panning features.

Keys:

•       = increase start address value
  

•       = decrease start address value
  

ARROW UP = increase vertical panning value ARROW DOWN = decrease vertical panning value ARROW LEFT = decrease horizontal panning value ARROW RIGHT = increase horizontal panning value PAGE UP = decrease split screen scanline value PAGE DOWN = increase split screen scanline value ESC = exit

Benchmark

Performs a series of video memory access speed tests. Two values are given: MB/s = the memory bandwidth of the video subsystem in megabytes per second; fps = how many times per second a single video page can be filled with a fixed character / attributes pair. This is an ideal condition and represents the maximum fill rate. Both values depend not only on the video card and bus speeds but also on the CPU performance.

Keys: ESC = exit r = repeat tests

Video modes available

Name Format Box Resolution 0,1 40x25 8x8 320x200 0*,1* 40x25 8x14 320x350 0+,1+ 40x25 9x16 320x400 2,3 80x25 8x8 640x200 2*,3* 80x25 8x14 640x350 2+,3+ 80x25 9x16 720x400 7 80x25 9x14 720x350 7+ 80x25 9x16 720x400 80x43 8x8 640x350 80x50 9x8 720x400 80x28 9x14 720x400 80x30 8x16 640x480 (multisync monitor only) 80x34 8x14 640x480 (multisync monitor only) 80x60 8x8 640x480 (multisync monitor only)

BEWARE: modes 80x30, 80x34, and 80x60 require a multisync monitor and they may damage very old VGA only 31.5 kHz monitors.

All Points Addressable (APA) tests

Circles demo

Shows a bunch of concentric circles that rapidly change their color. Useful to check the screen aspect ratio.

Keys: ESC = exit

Lines demo

Shows two lines (green and red) that rotates in opposite directions. In video modes with only one available page the lines could be only partially drawn (it depends on how fast the CPU, bus, and VGA are).

Keys: ESC = exit

Palette demo

Fills the screen with the color palette.

Keys: ESC = exit

Worms demo

Draws a bunch of worms that crawl on the screen.

Keys: ESC = exit

Split & Pan demo

This demo shows the split screen and panning features.

Keys:

•       = increase start address value
  

•       = decrease start address value
  

ARROW UP = increase Preset Row Scan value ARROW DOWN = decrease Preset Row Scan value ARROW LEFT = decrease Horizontal Pel Panning value ARROW RIGHT = increase Horizontal Pel Panning value PAGE UP = decrease split screen scanline value PAGE DOWN = increase split screen scanline value M = change Pixel Panning Mode value ESC = exit

Scrolling demo

This demo smoothly scrolls two vertical bars horizontally using the AC horizontal pel panning register and the CRTC start address.

Keys:

•       = increase scrolling amount
  

•       = decrease scrolling amount / pause
  

ESC = exit

Benchmark

Performs a series of video memory access speed tests. Two values are given: MB/s = the memory bandwidth of the video subsystem in megabytes per second; fps = how many times per second a single video page can be filled with a fixed color value. This is an ideal condition and represents the maximum fill rate. Both values depend not only on the video card and bus speeds but also on the CPU performance.

Keys: ESC = exit r = repeat tests

Video modes available

Name Col. Resolut. Pages Mode
04 4 320x200 1 CGA comp. 06 2 640x200 1 CGA comp. Dh 16 320x200 8 planar Eh 16 640x200 4 planar Fh mono 640x350 2 planar 10h 16 640x350 2 planar 12h 16 640x480 1 planar 13h 256 320x200 1 chain4 256 160x120 13 planar (multisync monitor only) Q 256 256x256 1 chain4 256 296x220 4 planar Y 256 320x200 4 planar X 256 320x240 3 planar 256 320x400 2 planar 256 360x270 2 planar 256 360x360 2 planar 256 360x480 1 planar 256 400x300 2 planar (multisync monitor only)

BEWARE: modes 160x120 and 400x300 require a multisync monitor and they can damage very old VGA only 31.5 kHz monitors.

LICENSE

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Authors

Copyright (C) 2019 Marco Bortolin Portions of code by Robert C. Pendleton and released in the public domain.