Dosbox.conf

From DOSBoxWiki

dosbox.conf is a configuration file located inside the same folder as the DOSBox binary (If you are using Linux, you first have to issue the command CONFIG -writeconf dosbox.conf inside of DOSBox. Afterwards, the dosbox.conf file will be written to your home directory). If an error message pops up telling you that the file cannot be created, you may want to run touch dosbox.conf in your home directory to first create an empty file. It contains various system settings and initialization values that define your emulated environment. Everything can be controlled by editing this file or if you like through more graphically oriented Front Ends. You can also create separate dosbox.conf files for multiple host environments (which is helpful in playing various DOS games that expect various types of hardware).

The configuration file is broken into separate sections which contain section settings. Many of these settings do not need to be fully understood to configure DOSBox, but it is helpful to know where to look. You should also be aware that anything to the right of the a # to the end of the line is considered a comment as is totally ignored by DOSBox when it loads.

[sdl]

This section contains all of the low level system settings for how DOSBox interacts with your real hardware. You can define what resolutions are emulated, how DOSBox should treat errors or listen to your keyboard and mouse. You can often achieve a fair level of optimization by working with these setting, though for the most part leaving them at their default settings will create the best experience. These settings are passed on to the SDL Library which handles low level things like input and thread priority.

fullscreen = true | false: Start DOSBox directly in fullscreen.; Default is false.; (since 0.??)

fulldouble = true | false: Use double buffering in fullscreen.; Default is false.; (since 0.??)

fullresolution = width x height | original: The resolution to use for fullscreen. If original is specified, DOSBox will try to switch the screen resolution to best match the resolution request by the application. For example, if a game in DOSBox is requesting a graphics screen resolution of (320 x 240) while your desktop is (1280 x 1024), DOSBox will perform the switch or try other resolutions that closely matches it, e.g. (400 x 300) if (320 x 240) is not available.; Default is original.; (since 0.62)

windowresolution = width x height | original: Scale the window to this size IF the output device supports hardware scaling (i.e. any output other than surface). Note that the window size actually has a fixed 1.6 aspect ratio, so if you ask for 1280x1024, you'll end up with a squished 1280x800 window. original means 1x zoom and will resize as the emulator switches graphics modes.; Default is original.; (since 0.62)

output = surface | overlay | opengl | openglnb | ddraw: What to use for output.; Default is surface.; (since 0.??)

autolock = true | false: Mouse will automatically lock, if you click on the screen.; Default is true.; (since 0.??)

sensitivity = 1..1000: Mouse sensitivity.; Default is 100.; (since 0.??)

waitonerror = true | false: Wait before closing the console if DOSBox has an error.; Default is true.; (since 0.??)

priority = when-focused,when-minimzed: Priority levels for DOSBox. Second entry behind the comma is for when DOSBox is not focused/minimized. Valid priorities are: lowerest, lower, normal, higher, highest, and pause.; Default is higher,normal.; (since 0.??)

mapperfile = path-to-mapper-file: File used to load/save the key/event mappings from.; Default is mapper.txt.; (since 0.??)

usescancodes = true | false: Avoid usage of symkeys, might not work on all operating systems.; Default is true.; (since 0.??)

Deprecated parameters

fullfixed = true | false: Deprecated as of 0.65. See fullresolution.; (since 0.??)

fullwidth = width: Deprecated with 0.62. See fullresolution.; (since 0.61)

fullheight = height: Deprecated with 0.62. See fullresolution.; (since 0.61)

[dosbox]

The DOSBox section contains various settings that does not really fit into any of the other sections, like the language used in DOSBox help texts, where to store screen captures, etc.

language = path-to-language-file: Select another language file.; Default is none.; (since 0.??)

memsize = nn: Amount of high memory (in megabytes) available to programs.; Note: DOSBox always allocates 1 MB of low memory, so the total amount of memory equals 1 MB of low memory, plus whatever is allocated for high memory.; Default is 16 (MB).; (since 0.??)

machine = hercules | cga | tandy | vga

The type of machine (specifically the type of graphics hardware) DOSBox tries to emulate.

Default is vga.

Definitions are as follows:

VGA (Video Graphics Array): IBM's graphics system introduced with the PS/2. True VGA supports 16 colors at 640x480 resolution, or 256 colors at 320x200 resolution (and not 256 colors at 640x480, even though many people think it does). VGA colors are chosen from a palette of 262,144 colors (not 16.7 million) because VGA uses 6 bits to specify each color, instead of the 8 that is the standard today. (info taken from http://www.pcguide.com/ref/video/stdVGA-c.html. See also http://en.wikipedia.org/wiki/Video_Graphics_Array and http://members.chello.at/theodor.lauppert/games/vga.htm)

Tandy: Refers to the additional graphics modes available on a Tandy 1000 or PCjr, which included 160x100x16, 160x200x16, 320x200x16, and 640x200x4. The Tandy RL/SL/TL series also added a 640x200x16 mode. (info taken from http://www.mobygames.com/attribute/sheet/attributeId,31/)

CGA (Color Graphics Adapter): Refers to IBM's first color graphics card. The CGA supports several different modes; the highest quality text mode is 80x25 characters in 16 colors. Graphics modes range from monochrome at 640x200 (which is worse than the Hercules card) to 16 colors at 160x200. However, for gaming, by far the most common mode was 4 colors at 320×200 pixels. These four colors, however, could not be freely chosen from the 16 CGA colors ? there were only two official palettes for this mode:

Magenta, cyan, white and background color (black by default). (much more common for gaming)
Red, green, brown and background color (black by default). (Can sometimes be selected as an alternate on some games).

Note that VGA fully supports most CGA modes, so you should be able to leave DosBox in VGA mode and play most CGA games.

(info taken from http://en.wikipedia.org/wiki/Color_Graphics_Adapter, http://www.pcguide.com/ref/video/stdCGA-c.html, and http://members.chello.at/theodor.lauppert/games/cga.htm)

Hercules: Refers to a graphics card developed by Hercules Computer Technology as a competitor to CGA for monochrome monitors. Hercules systems generate both high-resolution text and graphics. The resolution is 720 by 348 and only a single color is supported. (info taken from http://www.webopedia.com/TERM/H/Hercules_graphics.html and http://en.wikipedia.org/wiki/Hercules_Graphics_Card)

(since 0.??)

captures = path-to-capture-directory: Directory where things like music (wave and MIDI) and screenshots are captured when special keys CTRL-F5 and CTRL-F6 are used. Screenshots will be captured and saved as (PNG)? files with a resolution of 320x200.; Note: The capture directory will not be created automatically - you must create it before you start capturing music and screenshoots, otherwise nothing will be saved.; Default is capture.; (since 0.62).

[render]

The rendering (drawing) section controls methods that DOSBox uses to improve the speed and quality of the graphics displayed on the screen. E.g. it can "forget" (skip) the every 3rd screen update (which will save time), or it can try to smooth out some of the coarse low-resolution graphics that was used on old displays, but which looks bad when shown on a modern, high-resolution screen.

frameskip = nnn

How many frames DOSBox skips before drawing one.

Default is 0.

aspect = true | false

Do aspect correction.

Default is false.

scaler = normal2x | normal3x | advmame2x | advmame3x | advinterp2x | advinterp3x | tv2x | tv3x | rgb2x | rgb3x | scan2x | scan3x

Scaler used to enlarge/enhance low resolution modes.

normal: nearest-neighbour scaling (big square pixels)

scan: like normal, but with horizontal black lines

tv: like scan, but with darker versions of data instead of black lines

advmame: smooths corners and removes jaggies from diagonal lines

advinterp: identical to advmame

rgb: simulates the phosphors on a dot trio CRT

Default is normal2x.

Other scalers need added here: none, hq2x, hq3x, 2xsai, super2xsai, supereagle

[cpu]

The CPU section controls how DOSBox tries to emulate the CPU, how fast the emulation should be, and to adjust it. DOSBox offers 4 differents methods of ((/cpu/core/Intro|CPU emulation)).

core = simple | normal| full | dynamic | auto

CPU core used in emulation. auto switches to dynamic if appropriate.

Default is auto.

cycles = nnnn | max | auto

Amount of instructions DOSBox tries to emulate each millisecond. Set to max to automatically run as many cycles as possible. auto setting switches to max if appropriate.

OBS: Setting this higher than your machine can handle is bad!

Default is auto.

cycleup = nnn

Amount of cycles to increase with keycombo.

Default is 500. Setting it lower than 100 will be a percentage.

cycledown = nnn

Amount of cycles to decrease with keycombo.

Default is 20. Setting it lower than 100 will be a percentage.

[mixer]

Here you can define the quality of emulated audio. (more) ...See Sound

[midi]

Here you can define any MIDI related settings. The term MIDI is commonly used to refer to background music found in games, but specifically it refers to synthesizer audio (which can be passed directly from emulated games to modern hardware. (more) ...See Sound

[sblaster]

Sound Blaster related settings. (more) ...See Sound

[gus]

Gravis Ultra Sound related settings. (more) ...See Sound

[speaker]

PC Speaker related settings. (more) ...See Sound

[joystick]

Joystick related settings. (more)

[serial]

Serial Port related settings. (more)

This is an example of how to configure an actual serial port for I/O use:

serial1=directserial realport:com1

[dos]

Conventional Memory and Extended Memory related settings as well as the keyboard layout. (more)

[ipx]

IPX Networking related settings. (more)

[autoexec]

Here you can define the contents of the AUTOEXEC.BAT file (which is executed immediately after DOSBox is initialized). Thus any commands listed here will be performed each time DOSBox is used (more)

Retrieved from "http://www.dosbox.com/wiki/Dosbox.conf"