Configuration Options

You should read the documentation page first, to get a quick overview on how FS-UAE works, and what you must do to get started.

This is the old configuration options page. It has been replaced with a new one.

Here is an example of a simple configation file:

amiga_model = A500
kickstart_file = C:/Amiga/Kickstarts/amiga-os-130.rom
floppy_drive_0 =  C:/Amiga/Floppies/Disk.adf

There are several options available to tune your Amiga experience. If you want the default value for an option, you do not need to specify the option at all. If you omit amiga_model, you get A500 mode automatically.

Amiga Model

amiga_model = A500

Specify the Amiga model you want to emulate. The default is A500. Valid values are:

  • A500 – A standard Amiga 500 with 512 KB chip RAM and 512 KB slow RAM, defaulting to Kickstart 1.3.
  • A500+ – A standard Amiga 500+ with 1 MB chip RAM, defaulting to Kickstart 2.04.
  • A600 – A standard Amiga 600 with 1 MB chip RAM, defaulting to Kickstart 2.05.
  • A1000Since 1.3.27. An Amiga 1000 with 512 KB chip RAM, defaulting to Kickstart 1.2.
  • A1200 – A standard Amiga 1200 with 2 MB chip RAM, defaulting to Kickstart 3.1.
  • A1200/020 – Amiga 1200 but with 68020 processor instead of 68ec020 – allows the use of Zorro III RAM
  • A4000/040 – Amiga 4000 with 2 MB chip RAM and a 68040 processor running as fast as possible, defaulting to Kickstart 3.1.
  • CD32 – A standard CD32 unit.
  • CDTV – A standard Commodore CDTV unit.

The amiga_model options configures FS-UAE with common hardware options. You can override the amount of RAM (and other hardware options) with other options.

accuracy = 1

You can lower the accuracy of the emulation to run it on lower-spec machines (not recommended unless needed). Valid values (1, 0, -1) range from 1 (most accurate), to -1 (fastest, least accurate). The default value is 1.

ntsc_mode = 0

Set to 1 to enable NTSC mode (60Hz). Most games are designed for PAL mode (50Hz), but some may be design for, or is compatible with, NTSC mode. You shouldn’t enable whis unless you know what you are doing. The default value is 0 (which means PAL mode).

kickstart_file = path/to/kickstart.rom

The path to a specific kickstart file. The path can be either absolute, or relative to the current working directory. The same is true for all paths in the configuration file. Generally, you do not need to specify the path to the kickstart directly, if you have a compatible kickstart file for the Amiga model stored in the (My) Documents/FS-UAE/Kickstarts.

kickstart_ext_file = path/to/extended-kickstart.rom

The path to the extended kickstart ROM (for CD32, …)

Memory Options

chip_memory = 1024

Override amount of chip memory, specified in KB. Must be a multiple of 512. The default value depends on the Amiga model.

slow_memory = 512

Override the amount of “slow” memory, specified in KB. Must be a multiple of 256. The default value depends on the Amiga model.

fast_memory = 4096

Override the amount of Zorro II Fast memory, specified in KB. Must be a multiple of 1024. The default value depends on the Amiga model.

zorro_iii_memory = 65536

Override the amount of Zorro III Fast memory, specified in KB. Must be a multiple of 1024. The default value depends on the Amiga model. Requires a processor with 32-bit address bus, (use for example the A1200/020 model).


By default, FS-UAE grabs the mouse and keyboard input when it starts. You can prevent this by setting input_grab to 0.

Note: for FS-UAE <= 1.2.0 this option is called grab_input.
Note: for FS-UAE >= 1.3.23 this option is renamed to initial_input_grab.

input_grab = 0


Since 1.3.23. By default, FS-UAE grabs the mouse and keyboard input when you click on the window with the mouse. You can prevent this by setting automatic_input_grab to 0.

automatic_input_grab = 0


Enable emulation of bsdsocket.library. This will allow the Amiga OS to open TCP connections (use web browsers, etc). Only for Linux / Mac OS X currently. The default is 0 (off).

bsdsocket_library = 1


The following directory is scanned for kickstart ROMs. If you do not specify this path, and do have kickstarts in the default directory, you need to provide the path for a specific kickstart in kickstart_file. fs-uae uses WinUAE’s quickstart code for this, so if you haven’t got exactly the preferred ROM files the automatic configuration will fail. You should use kickstart_file/kickstart_ext_file instead in this case.
The default is (My) Documents/FS-UAE/Kickstarts

kickstarts_dir = path/to/dir/with/kickstarts


Save states are stored in save_states_dir.
The default is (My) Documents/FS-UAE/Save States

save_states_dir = path/to/save/state/dir


Floppy overlay ADFs (sdf) are saved in floppy_overlays_dir.
The default is (My) Documents/FS-UAE/Floppy Overlays

floppy_overlays_dir = path/to/floppy/overlays/dir


CD32/CDTV flash memory files are stored in flash_memory_dir.
The default is (My) Documents/FS-UAE/Flash Memory

flash_memory_dir = path/to/state/dir


Directory where controller config files can be placed.
The default is (My) Documents/FS-UAE/Controllers

controllers_dir = path/to/dir


Directory where log files are put.
The default is (My) Documents/FS-UAE/Logs

logs_dir = path/to/dir


Search for (relative) hard drives paths relative to this dir (in addition to current directory).


Search for (relative) CD-ROM image paths relative to this dir (in addition to current directory).


Search for (relative) floppy image paths relative to this dir (in addition to current directory).


This directory will be used instead of (My) Documents/FS-UAE/ to calculate the other default directories.

base_dir = path/to/base_dir


The host device mapped to Amiga joystick port 0. If not specified, a mouse will be configured in port 0. Valid values for device:

  • mouse
  • keyboard
  • name of connected game pad or joystick
  • nothing
joystick_port_0 = mouse


The device connected to port 1. If not specified, a the first joystick/gamepad connected to the computer will be used, if the joystick/gamepad is supported. Otherwise it defaults to keyboard emulation (cursor keys + right CTRL). To force keyboard emulation, specify “keyboard”

joystick_port_1 = joystick

You can also choose to use specific gamepads/joysticks in the ports. In this case, you specify the device names. If you have more than one device of the same model, the second is referred to by appending a space and #2 (and so on). The device names are case insensitive.

joystick_port_0 = SPEED-LINK COMPETITION PRO #2


Emulated parallel port joystick 1. A few games support parallel port joysticks (to support a total of four connected joysticks).



Emulated parallel port joystick 2. A few games support parallel port joysticks (to support a total of four connected joysticks).



Where n is a number from 0 to 3: Specify what emulated Amiga device is connected to joystick port 0. If not specified, this value will be automatically chosen based on the emulated Amiga model and the host device associated with the joystick port. Valid values are:

  • joystick
  • mouse
  • cd32 gamepad
  • nothing

Not all combinations of joystick_port_n and joystick_port_n_mode are valid. For instance, a host joystick cannot currently be mapped to an Amiga mouse.


You specify paths for floppy images in floppy_drive_0 through floppy_drive_3. The number of internal floppy drives will be set according to the highest drive number specified here.

floppy_drive_0 = path/to/adf_or_ipf
floppy_drive_1 = /path/to/adf_or_ipf
floppy_drive_2 = path/to/adf_or_ipf
floppy_drive_3 = path/to/adf_or_ipf


Set volume to 0 to disable floppy drive sounds. Max volume is 100. The default value is 20.

floppy_drive_volume = 20


Set the speed of the emulated floppy drives, in percent. The default is 100. For example, you can specify 800 to get an 8x increase in speed. Use 0 to specify turbo mode.

floppy_drive_speed = 100


In order to enable floppy-swapping, you must list all floppy images which is to appear in the floppy list. You can use floppy_image_0, floppy_image_1, floppy_image_2, and so on. There is no specific limit to have many items you can specify, but the GUI does not initially support scrolling, so if you have 20+, you will not see all items in the GUI yet.

floppy_image_0 = path/to/adf_or_ipf
floppy_image_1 = path/to/adf_or_ipf
floppy_image_2 = path/to/adf_or_ipf
floppy_image_3 = path/to/adf_or_ipf
floppy_image_4 = path/to/adf_or_ipf


If you are emulating CD32 or CDTV, you specify the path to the CD-ROM image here (CUE/BIN and ISO images are supported).

cdrom_drive_0 = path/to/cue_or_iso


Similar to floppy_image_n, but for CD-ROMs

cdrom_image_0 = path/to/cue_or_iso


A hard disk image file (.hdf) can be mounted within fs-uae with options hard_drive_0 through hard_drive_9. Currently, only default “geometry” is supported. (surfaces: 1, reserved: 2, sectors: 32 and block_size: 512)

hard_drive_0 = path/to/image.hdf

Instead of using hard disk image files, you can also mount folders as drives. This is enabled by pointing the hard_drive_x options at a folder on you computer:

hard_drive_0 = path/to/folder

New in version 0.9.11: You can also mount a zipped folder as a drive. It will be mounted read-only, but otherwise works as a normal folder mount.

hard_drive_0 = path/to/


By default, for mounted folders, the volume name inside the Amiga is the name of the folder. You can override this on a per-drive-basis:

hard_drive_0_label = My Volume


Mounted hard drives, which would otherwise by mounted writable, can be forced to read only with this setting.

hard_drive_0_read_only = 1


The option viewport specifies a crop rectangle to apply to the Amiga video-out. The default, if not specified, is to calculate this automatically (auto-scaling). To force an uncropped viewport (and effectively disable autoscaling), you can specify:

viewport = * * * * => 0 0 752 574

If auto-scaling does not work perfectly for a game, and you want a cropped output, you can specify any crop rectangle (x y width height), The following viewport is appropriate for many games:

viewport = * * * * => 74 36 640 400

Often, Amiga games have viewports with varying size and position. The default auto-scaling system works well with many games, but not all. You can modify the auto-scaling algorithm by specifying patterns to replace. The viewport setting will be consulted each time the auto-scaling algorithm chooses a new viewport.

Here are some examples:

The following viewport pattern will match if the auto-scaling algorithm thinks the viewport should be 640×400 and start at 74 from the left. The top can be anything (*). Now, the top parameter will be forced to 20. A * on the right side of => means to keep the existing value, while a * on the left side means to match any value.

viewport = 74 * 640 400 => * 20 * *

The following viewport specification does nothing:

* * * * => * * * *

This following viewport is a simple translation (74 40 640 400 => * 36 * * would behave the same):

74 40 640 400 => 74 36 640 400

You can specify more than one pattern by separating them with commas. In this case, the first matching pattern will be used. Here is a viewport specification which works perfectly with Pinball Dreams: (this basically says: keep the viewport 74 28 640 524 as it is, and all other viewports will be forced to 74 36 640 512.

viewport = 74 28 640 524 => * * * *, * * * * => 74 36 640 512

This one is great for Turrican II:

viewport = 74 * 640 384 => 74 36 640 424

But rembember, many games work perfectly with the builtin viewport detection, and if you do not want auto-scaling, you can disable it by specifying a fixed viewport of your choice.


You can override the title displayed in menu mode.

title = Custom Title


You can also override the sub-title displayed in menu mode.

sub_title = Custom Sub-Title


Net play server to connect to (IP address or host name).

netplay_server =


Net play server port to connect to. The default is 25100.

netplay_port = 25100


A tag name for the player, up to three letters long. This tag will be shown to other players. The default is UNK (Unknown).

netplay_tag = ABC

 Deprecated Options

Some options are renamed to make the names more intuitive or consistent with other options (both old and new names will work for now, but please use the new option names):

model   => amiga_model
sync    => video_sync
grab_input => input_grab
  • input_grab (deprected in 1.3.23) – use initial_input_grab instead.

25 thoughts on “Configuration Options

  1. awesome emulator is there a way to increase chipmem past 8mb lik give it a gig. also on winuae you can increase the memory on the motherboard i forgot what they call it but you could go up to 64MB. also on uae there is this config option called gfx_colour_mode= and you can choose between 8, 16,24, or 32 bit put that into next version so when you want true color we have it also for all the MEMORY stuff make unlimited so this way if there is something that needs to be run you’ll have plenty of ram to do so

    • Hi, FS-UAE uses true color mode by default. You can use the video_format option to change between 16 and 24/32-bit color mode.

      You can use the option zorro_iii_fast_memory to give the Amiga 1 GB RAM. (This requires an Amiga model with 32-bit address bus, for example A1200/020 or A4000/040). I have seen WinUAE supports “32-bit chip ram” or something like that, but I don’t know when this would be useful, and no-one has requested it for a specific purpose, so this is why 32-bit chip RAM is not currently supported.

  2. Hi, Is there any way of changing all the hardcoded paths, or atleast overriding them through command-line.
    First of all, there is no config file created where the help here says it will be created (my documents/…), all the folders there are created just fine though, they are just empty.

    I have tried fs-uae.exe -c “path/to/myconfig.conf”, but that did nothing at all.

    I am mainly hoping there is a way to define a config through the command line, and also ideally to define what floppies to load.

    Can fs-uae solve this as I run all other emulators through xbmc for windows and they all support command-line arguments? If not, I’ll have to find another one, though apart from this issue I have, its working great.

    • Hi, yes, FS-UAE can do all the things you have mentioned.

      First of all, no paths are hardcoded. You can override the options “floppies_dir” etc. The “base_dir” option is an easy way to implicitly change all the other paths, for instance (using Windows paths as example):
      base_dir = D:/FS-UAE – All options, including base_dir can be given as command line parameters, for instance: fs-uae.exe --base_dir=D:/FS-UAE Options given as arguments override options in configuration files.

      No configuration file is created by default (and the documentation does not say so either, I hope), but Default.fs-uae will be loaded if it exists. If you want to load a custom configuration file, just give the path to fs-uae (no “-c” parameter), for example: fs-uae.exe D:/FS-UAE/CustomConfig.fs-uae

      Regarding floppies, as with all other options you can set floppy_drive_0 (and floppy_drive_1, etc) either in a configuration file, or with program arguments: --floppy_drive_0=... All options, including path and floppy options, are documented here on this site.

      • Ah, that was the missing link i was looking for, just --[configoption], [ed.: use two dashes] very nice.

        And hardcoed might have been too harsh a word, but since I couldn’t find any info on how to specify a config file, i assumed it always looked in “My docs/…/default.fs-uae”.

        Where the heck i got the -c from I don’t know, maybe I got it mixed up with some other emulator 🙂


        Another thing: Is the path “issue” the same from the command line too? In that I have to escape the backslash or use regular slashes for paths?

        • Note that it is --option=value with two dashes (WordPress displayed the comment wrong, I have updated the comment with code tags to make it display correctly). I have also now made it more clear on the User Manual page how custom configuration files are loaded.

          Boolean options on the command-line can also be shortened. i.e. --fullscreen is the same as --fullscreen=1 and --no-fullscreen is the same as --fullscreen=0.

          Regarding paths and backslashes: No, when specified on the command line, FS-UAE does not want the backslashes to be escaped –but your shell may require you to escape backslashes for single backslashes to “reach” FS-UAE.

          • Cool, thanks a bunch for the quick feedback! Keep up the good work.

  3. Hi, thanks it works perfecty with the Amiga theme on a widescreen display after altering the size a bit. ONE THING: swapping floppies seems to be unconfortable for testing new floppy images (.adf) etc. Every floppy image has to defined first in the config file to be able to load from the menu later on? Would be better if you could just browse your folder of floppies. ALSO there could be more options for sound output, in detail sound latency. I’d like to minimize the output latency for trackers and sound playback on the keyboard. Grafically & menu-vise very nice.

    • Hi! Yes, there is no (file system) floppy browser yet. In the meantime, launching FS-UAE through FS-UAE Launcher (available here) should make it easier for you to run floppy disks.

      Regarding audio, I have just released version 1.3.18. See Audio Options for a description of the new option you can use to set the internal audio buffer. If you set it too low, you’ll get frequent buffer under-runs. For testing, you can use Ctrl+F10 to see a graph of the audio buffer (blue bars) where the green line is the target buffer size and the white line is the actual buffer fill.

      Also, you may be able to tweak OpenAL itself for better performance / lower latency but this is outside the scope of FS-UAE.

  4. This is amazing! Got up and running in short order with DPaint IV and Scorched Tanks in no time last night. What a clean interface especially running on the big screen in the living room. I am having a few path problems though.

    I’m running on a Mac with OS 10.7.4. I’ve configured everything to match my A500 that is in the closet but I noticed in the configuration file the path to the kickstarts is still specified as C:/Amiga/Kickstarts/SOME_KICKSTART.ROM. The 2.0 rom I specified is found and works no problem even though on MacOS this path is nonsense. It should be ~/Documents/FS-UAE/Kickstarts/. Moving on, I dropped my few .adf files into the Floppies directory that was created automatically but they are not listed by the emulator when it is running to be inserted into a drive. If I specify floppy_drive_0 = DPaintIV.adf the emulation finds the disk and boots without a problem. I’ve tried specifying another path in both the C:/Amiga/Floppies format and in the OSX styles ~/Documents/FS-UAE/Floppies (and /Users/MY_USER/Documents/FS-UAE/Floppies) and FS-UAE shows “Couldn’t create floppy directory” and floppy disk images are not listed to be able to switch on the fly. Similarly a hard drive image from my A500 that I have backed up wasn’t seen by the emulation with the same kind of error.


    • Sorry for late reply. If you download the config file from this site, the paths are examples only and should be replaced. The kickstart will not be found if the path is wrong, but a built-in kickstart (from AROS) will be used if the kickstart is not found.

      Regarding floppies, the GUI floppy list is not automatically populated -you must use floppy_image_0… options to fill the list manually. If the floppies are put in the Floppies directory, you can refer to them by name only (without path) in the config file.

      Regarding the hard drive image, you have provided too little information for me to comment. A great place to get more detailed help about FS-UAE is on this forum:

  5. I got 1.2.1 to run on my Windows XP desktop. However, the emulation will not boot to a configuration file unless it is named Default.fs-uae. That means that if you store more than one configuration file in the Configurations directory, you must rename the Default,fs-uae file you are using and rename the one you are going to use Default,fs-uae.

    Is ther a workaround for this?

  6. Neither of the versions work on my Windows XP desktop. In version 1.2.1, even though the configuration file has a .uae extension, my only chioces for opening it are: WordPad, Internet Explorer and WinUAE.

    In version 1.3.14, I lose my mouse pointer when the configuration boots.

    I have log files from both if you would like them.

    • The extension for configuration files is .fs-uae, but the installer does not currently associate the configurations files with the program. You can manually choose to open the files in “another program” and the browse to the location of FS-UAE.exe. Regarding the mouse pointer, this is intentional, as FS-UAE grabs the input. You can release it with the middle mouse button, for instance (or disable the initial input grab with the option input_grab = 0).

      • Actually, I got the configuration files to automatically associate with fs-uae via both the “Open With” menu and by just double clicking them. Now I can choose “Open With” or double click the file. I added the fs-uae.exe to Internet Explorer File Types. Thanks for the mouse tip.

        • If you have made multiple Config files, can you just double click and assosiate it with the launcher?

          • You can associate .fs-uae files with FS-UAE, but not currently with FS-UAE Launcher. This will be possible soon.

  7. Hello, is it possible to change the path globally, instead documents/FS-UAE just User/Games/Amiga/ ? Thank you!

    • Yes, you can use ~/.config/fs-uae/fs-uae.conf instead of Default.fs-uae and set the option base_dir. Or you can add base_dir as a program argument to fs-uae.

      • Frode, please explain what you have to do to change the path instead of using the mydocuments folder all the time

  8. Hi! I wish to really thank you for your great work! I’m enjoying FS-UAE on my Macbook Pro and it’s awesome! Keep it up! Ciao! Enrico B.

    • Hi, the Super model was never “officially” supported, more of a test model (but I don’t plan to remove it). I did however forget to add info about the new “A4000/040” model. Thanks 🙂

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