AspeQt User Manual
 version 1.0.0 preview-7


AspeQt is a cross-platform, free and open source Atari 8-bit serial peripheral emulator. The name is an acronym for Atari serial peripheral emulator for Qt, Qt being the cross-platform application development framework used by AspeQt.

You can download AspeQt from the SourceForge project page.

AspeQt emulates various Atari 8-bit peripherals like disk drives and printers via a SIO2PC cable. If you are familiar with software like SIO2PC, APE, Atari810, AtariSlO etc., you probably won’t have any problems getting used to AspeQt.

Even though AspeQt is not fully mature yet, it is easy to use and, despite its shortcomings, has many features that you may find useful, the highlights being:

System Requirements

AspeQt currently runs under Windows, Linux and Mac OS X. Other Unix-like operating systems shouldn’t require too much effort. The absolute minimums aren’t easy to tell but a modern Linux distribution with Qt 5.2.1 libraries or a Windows XP (or newer) is recommended.

Although AspeQt is reported to run on a Pentium 233 MMX, a modem processor and a decent amount of RAM is strongly recommended for smooth operation. It runs fine on 64-bit CPUs.

In order to do anything useful with AspeQt, you will need an Atari 8-bit computer and a SIO2PC cable. SIO2PC cable is an interface that connects the Atari’s serial bus to the PC’s serial port. Since many newer PCs lack a real serial port, you may need a UART card, or a high quality Serial-to-USB adapter (FTDI chip based devices were tested successfully, others may not work as intended) or a SIO2PC USB interface (instead of serial), If you opt for the later however, please note that the “AtariMax SIO2PC Universal Interface USB Edition” is not officially supported as it uses proprietary USB device drivers.

You can get a RS232 or Serial-to-USB based SIO2PC cable from Atari8Warez

You don’t need any real Atari disk drives or printers to use AspeQt.


On Windows, AspeQt comes with all the required DLLs in a ZIP file. Just unzip the archive to a folder and run aspeqt.exe. You may manually create shortcuts on your desktop, start menu and quick launch bar if you want. Future releases may include an installer but it doesn’t exist yet.

On Linux, AspeQt comes as a zipped source. You will need Qt 5.2.1 libraries and build tools to compile. After installing them, please follow the instructions in compile.txt that comes in the zip file. Pre-built packages of earlier/current versions for popular Linux distributions may be obtained from

If you want to use the AtariSlO backend, which is highly recommended if you have a real RS-232 serial port, you will need the AtariSlO package. Please follow the documentation that comes with that package to compile and install it.


In order to be able to use AspeQt, you need to configure it to suit your hardware. When it’s running for the first time, a dialog will pop up asking you if you wish to open the configuration dialog. Click “Yes” to open the Options dialog. You can also access this dialog from the Tools/Options menu item.

On Linux, you have to choose a serial I/O backend first. If you have installed the AtanSlO package and you have a RS-232 port, the recommended way is to use the AtariSlO backend. If you have a USB adapter or you don’t want to use AtariSIO for any other reason, choose the standard serial port backend. This is also the only available backend on Windows.

Configuring the standard serial port backend
First, enter a port name. On Windows, it should be something like COM1, COM2 etc. Check the device manager to see which one of them is installed. On Linux, it should be /dev/ttyS0, /dev/ttyS1 etc. for RS-232 ports or /dev/ttyUSB0, /dev/ttyUSB1 etc. for USB adapters.

Next, you will have to select a handshaking method. The handshaking method tells AspeQt which one of the RS-232 pins is connected to Atari’s command line. There are 3 supported methods: RI, DSR, CTS and NONE. Check your SIO2PC interface’s documentation to learn which one of them is used for your cable. Note that NONE (no handshaking) is highly experimental and not recommanded for day-to-day use, in this mode AspeQt will ignore Atari's command line (SIO7) and will monitor the COM port's RXD (Atari SIO5) line instead. No handshaking mode was included to experiment with wireless (bluetooth) serial interfaces.

The “High speed mode baud rate” combo box selects the transfer speed to be used for the high speed mode. Some OS /DOS for the Atari supports higher transfer speeds than the standard 19200 bits per second. Not all DOS /OS are capable of using 3x speed and some treat 2x as a special case for XF551 drives, so you may need some experimentation to find the best setting. 1x option is provided for unreliable connections, like when using a cheap USB adapter or when running AspeQt under virtualization software and/or on a slow CPU computer.

If your serial port supports arbitrary bit rates, you may check the “Use non-standard” speeds check box and select a POKEY divisor to be used in high speed mode, the lower the divisor, the higher the speed. Usually real COM ports and some VCP (Virtual COM Ports) don't support arbitrary baud rates, FTDI chip based serial-to-USB cables do support arbitrary baud rates, and are thus the recommanded type of cable for use with AspeQt.

The exact formula for the nominal speed is:

baudRate = clock/ (2*(divisor+7))

Where dock is ~1,773,447 for PAL, and ~1,789,772 for NTSC, however, it’s not always possible to reach nominal speeds. So, 1x is divisor 40, 2x is divisor 16 and 3x is divisor 8. Divisor 0 is ~l26kbits/second and that means approximately 6x.

Please note that very few OS/DOS will be able to function with such high speeds. Currently the only tested software that can reach divisor 0 with AspeQt is the hisio OS patch.  As a final warning, some Atari 8-bit computers have capacitors connected to their SIO lines that can interfere with high speed transfers. In short, speeds beyond 3x are not guaranteed to work in every case.

Configuring AtariSIO backend

Note: AtariSIO is available under Linux only!

After installing and running the AtariSIO module and making sure that you have the required permissions, you just need to enter a device name which should be /dev/atarisio0 under normal circumstances and select a handshaking method as described above for the standard serial port backend. Please refer to AtariSIO documentation on how to build and install AtariSIO.


After making sure that you installed and configured AspeQt correctly, you can start using it with your Atari. If you used similar software before, it should be fairly straight forward.

Disk images
Instead of using real disks, AspeQt uses disk images. These are regular files that contain an image of an Atari disk. There are several formats, the most common being the .atr format, currently AspeQt only supports .atr, .xfd,  atx (still in development), and .pro  formats. Future releases may provide support for .scp, .dcm, .di and gzipped (.atz. atr.gz, .xfz and .xfd.gz) formats.

AspeQt emulates 15 disk drives. You have one slot for each of them, labeled D1 through  DO (letter O). D9 through DO are only supported by SpartaDOS X and compatible DOS (see SDX manual for details on supported disk drive identifiers). You can make AspeQt to show only the first slot, the first 8 slots, or all 15 slots using options in DISK and WINDOW menu items.

+ To hide/show drives D9 through DO, use menu item Disk/Hide drives D9-DO (CTRL+H),

+ To toggle AspeQt mini mode use menu item Window/Toggle Mini Mode (CTRL+M), in mini mode AspeQt shows only the first drive slot,

To toggle shade mode in mini mode use menu item Window/Toggle shade mode (CTRL+S), in shade mode AspeQt shows a semi-transparent window which does not completely block the view of underlying UI objects,

Note that all drives are actually available for use with your Atari in all AspeQt display modes whether they are visible or not.

You can mount a disk image to an empty drive slot by:

You can see the result of your operation in the log display which is below the disk slots, if the operation is completed successfully, your Atari should be able to see the mounted disk image just like a real disk in a real drive.

You can use the tool buttons and context menu items to perform other operations like saving the disk image, enabling write protection for the image, reverting the image to its last saved state, ejecting (unmounting) the image, creating a new image and so on. You can also swap images using drag and drop.

Folder Images
Folder images provide a similar function to the features variously named as “PC mirror’, “Simulated disk”, “Share point” etc. by other peripheral emulators. This is basically a simulated Atari DOS2.5 disk. Instead of a disk image, you can mount a folder in your PC that contains some Atari files and Atari will see it as a disk with the same files in it.

Currently, the mounted folder will be seen as a standard DOS 2.5 disk and it’s sequantial access (Basic NOTE/POINT commands will not work as expected) and read-only . Although Folder Images are simulated and behave like Atari DOS 2.5, there are some differences. The most important difference is that each file can be as large as 8MB in size and file sizes are shown as number of bytes as opposed to number of sectors (unlike Atari DOS). Maximum number of files in the directory is 64 and subdirectories are not supported. Folder Images are also compatible with MyDOS, all versions of Spartados and SpartaDOS X. There may be issues with others.

Folder images are also bootable as of version 0.8.5, but since the folder image is a simulation of a standard DOS 2.5 disk, you can only boot into a DOS that is compatible with AtariDOS disk structure. There are two exceptions to this, first one is SpartaDOS, AspeQt will allow you to boot into a 3.2f version of SpartaDOS but there are some limitations. AspeQt will also allow you to boot into the standard version of MyPicoDOS 4.05. See the following section for for details and limitations:

Folder boot details and limitations:

To boot your Atari with a Folder Image, first mount a PC folder to disk slot 1 (D1:). Once mounted, right-click on the Folder name and select Folder Boot Options from the menu, select the DOS you would like the boot and click Apply. make sure AspeQt is ready to receive commands from your Atari and finally turn your Atari ON, selected DOS will be booted. You must select a DOS boot option if you mounted a Folder Image for the first time and you want to boot your Atari from that folder whenever the folder is mounted. You normally only select the DOS option once for each Folder Image. The Folder will remain bootable with the same DOS between AspeQt sessions.
AspeQt will copy the necessary DOS files into the mounted PC Folder to make it bootable. Do not keep any other DOS files (like dos.sys, dup.sys etc..) on that folder as they will be erased/replaced.

Note that you don't need to supply any DOS files, AspeQt distribution supplies the files necessary to boot your computer. These DOS files are copyright of their respective owners, Atari8Warez and AspeQt distributes those files with the understanding that they are either freeware, abandonware or public domain and are widely available for download through the internet. If you are the copyright holder of one or more of these files, and believe that distribution of these files constitutes a breach of your rights please contact Atari8Warez. We respect the rights of copyright holders and won't distribute copyrighted work without the rights holder's consent.

The following DOSes can be booted from a Folder Image:

Running Atari executables
Most Atari programs floating around on the internet come as Atari DOS executables. These files may have .exe, .com, .xex or any other extension. Instead of messing with disk image software and DOS, you may directly run these files in your Atari using AspeQt.

You can either drag and drop a file with .exe, com or .xex extension into any slot or you can use the menu item “File/Boot Atari executable” to access this feature. A dialog with the necessary instructions will pop up and the file will be loaded and run. You can leave the dialog open to boot from the same executable more than once. A reload button is provided which will reload the executable into memory. This button is intended for atari software developers who may be developing on the PC and testing their software after making changes to it. Reload button will ensure the most recent executable is loaded from the PC, and as such is mainly a convenience feature for such developers.

The executable booter has an optional high speed code which will allow you to load programs a lot faster. You can enable/disable it with the “Tools/Options/Emulation/Use high speed executable loader” check box. The high speed code is not able to cope with higher speeds than divisor 3 so check your configuration before attempting to load a file in this way.

Please note that this feature is not compatible with every executable and, in practice, it’s not even possible to implement such a loader. High speed loader has even more issues. So there will always be some programs that you won’t be able to run with the executable booter but hopefully the number of the compatibility problems will decrease with future versions of AspeQt.

Image explorer

Warning: This feature is constantly under development and may change with each release, so use it with caution.

As mentioned above, AspeQt uses disk images instead of real disks. These images may contain Atari files and it’s not always easy to extract them from an image or to add a file into an image. By clicking the ‘Image properties’ tool button or by using the context menu, you can explore the files in a mounted disk image.

There are various file systems (ways of putting files in a disk) used by Atari. AspeQt supports the most common one, the Atari Dos file system (including the most used variants, like Dos 2.5 and MyDos) fully, including MyDos style subdirectories. It also has read-only support for SpartaDos file system. Other file systems (like Dos 3.0) are not supported at the moment.

By using the tool bar buttons in the image explorer, you can drag and drop, extract, add, delete Atari files with optional text conversion. You can also drag and drop files between different images and rename files by pressing F2 after selecting the name or extension of a file. You can print a directory of files by clicking on the printer button.

Cassette images
AspeQt can playback cassette images in .cas format. These are PC files that contain data extracted from an Atari cassette. You can either drag and drop a file with .cas extension into any slot or you can use the menu item “File/Playback cassette image” to access this feature. A dialog with the necessary instructions will pop up and the file will be played back.

The cassette emulator can be configured to ignore the baud rate that is embedded in the image file in favor of a custom one. This may speed up the load times but can cause compatibility problems. You can enable/disable it with the “Tools/Options/Emulation/Use custom baud rate for cassette emulation” check box. When enabled, you can use the spin box below to set the custom baud rate. The available values range from 425 through 875 bps. These values are the lowest and highest speeds that the Atari OS can process. The normal speed is 600 bps.

The cassette emulation does not support rewinding or seeking in the images. This may change in the future versions.

Printer output
AspeQt emulates a generic text-only Atari printer. It only emulates the first printer device, that is “P1:” You can view, save or print the emulated printer output using the “File/View printer text output”. Support for ASCII and ATASCII is provided.

Running multiple instances of AspeQt (Sessions)
AspeQt allows you to save and load your disk sessions, that is, the order and names of the mounted images and their settings. You can access this feature from the “File/Open session” and “File/Save session” menu items. As of version 0.8.2 AspeQt fully implements multi session capability. This means you can now launch multiple instances of AspeQt using different session files and have different configurations for each session. This makes possible serving more than one Atari computer from one PC so long as you have more than one COM port and SIO2PC cable available. Simply create different sessions with different settings and save them to a permanent session file (a file with .aspeqt file extension).
If you plan on serving more than one Atari computer simultaneously, make sure that the PC is fast enough to handle similtaneous SIO requests as Atari SIO is very time critical and can fail if the requests are not serviced in a timely fashion. Experiment with the multi-session capability and  verify that it can be run reliably before you put it on serious use.

The following parameters can be configured for individual sessions (stored in each session file)

The following configuration parameters are global and apply to all sessions (stored in Windows registry)

The following configuration parameters apply when AspeQt is launched without a session file (stored in Windows registry)

To launch a session, create a shortcut (Windows) or a link (Unix/Linux) in a folder with the session file name as a command line argument:

An example of a shortcut for Windows would be:

"C:\Program Files\AspeQt\aspeqt.exe"  C:\Program Files\AspeQt\session.aspeqt

AspeQt client software for the Atari (AspeCl)

AspeQt also implements a client server device ($46) which communicates with the client module AspeCl that runs on the Atari computer.  AspeCl is a general purpose client module and incorporates the following functionalities:

AspeCl Usage (command line switches, at least one must be specified)

Aspecl  TS | TO | TF | DA | DS | DU | DM | DN

TS  => Set Date/Time on Atari

TO  => Set Date/Time on Atari and turn TD Line ON

TF  => Set Date/Time on Atari and turn TD Line OFF

DA[d/*]   => Toggle Auto-Commit ON or OFF on a given disk  (d) (where d is 1 to 9 and J to O, following SDX naming conventions) or on all (*) disks. Toggling auto-commit switch to ON will commit all pending changes to the affected disk image and all future changes will be comitted automatically. If the toggle is set ON on a newly created and mounted disk image (mounted locally by AspeQt), operator intervention will be required from the AspeQt side to assign a permanent file name to the image file before it's saved to PC hard disk.

DS[dd]   =>  Swap disks, where dd represents the drive numbers to be swapped (i.e DS1J will swap disks 1 and 10)

DU[d/*]   =>  Unmount disk(s). Will either unmount a single disk [d], or all disks [*]. Unmount will not unmount disks that have changes until the changes are commited. Disks set to "auto-commit" in AspeQt will be unmounted immediately as the changes to these images are commited automatically as they occur. So if there are pending changes for a disk when you want to unmount it remotely, first issue a DA remote command to the same disk to toggle auto-commit. Once auto-commit is toggled ON any pending changes will be commited to disk. You can then issue the DU command to unmount that disk remotely.

DM[fname.ext]  => Mount an existing disk image command will mount a supported disk image file (.atr, .atx, etc) into the first available disk slot. Command will return the used disk slot number to the Atari. It is important to note that  AspeQt needs to know where the disk image file resides on PC. AspeQt will look for the disk image file in the "Last Folder Image Directory". A Folder Image is a window into one of the PC directories where your Atari files may reside. This Folder Image does not need to be currently mounted to AspeQt but must have been mounted at least once before so that AspeQt knows the name of this directory. If a Folder Image has never been mounted, AspeQt will display an error message indicating that it does not know where to find the remotely requested disk image file.

DN[fname.ext].[1/2/3/4/5/6] => Create and mount a new disk image. Will create a new disk image with the given name, and mount it. The disk image will be created in the "Last Folder Image Directory" used by AspeQt and be mounted on the first available disk slot. Command will return the used slot number to the Atari.  It is important to note that  AspeQt needs to know where the disk image file will reside on PC. AspeQt will save the disk image file in the "Last Folder Image Directory". A Folder Image is a window into one of the PC directories where your Atari files may reside. This Folder Image does not need to be currently mounted to AspeQt but must have been mounted at least once before so that AspeQt knows the name of this directory. If a Folder Image has never been mounted, AspeQt will display an error message indicating that it does not know where to save the remotely created disk image file.

                                         The Disk Image can be created in the following capacities:
                                         1 - Standard Single Density (90KB)
                                         2 - Standard Enhanced density (130KB)
                                         3 - Standard Double Density (180KB)
                                         4 - Double sided, double density (360KB)
                                         5 - Double density Harddisk (256 bytes/sec, 65535 sectors, 16MB)
                                         6 - Quad density Harddisk (512 bytes/sec, 65535 sectors, 32MB)

Example: ASPECL DNmyhd.atr.6  => will create and mount a quad density harddisk .atr image with the name myhd

And here's an example of invoking AspeCl with multiple command line switches:

ASPECL TF DS18 DMBASICXE.ATR  => will set the date/time and turn TD line OFF, will swap disks 1-8, and will mount basicxe.atr disk image to the first available disk slot, returning back the slot number to Atari.

AspeCl compatibility

AspeCl is currently a command line based client which is fully compatible with and runs only under SpartaDos (v2.5 and up) and SpartaDos X versions. A seperate menu driven client for menu based DOS (like AtariDOS and MyDos versions) will be available in the future. Some of the functionality in AspeCl also depend on the underlying DOSes capabilities. For example setting the Date/Time from the PC is a DOS dependent feature as it requires specific Date/Time drivers from the DOS. Other functionality like mounting/unmounting/swapping disk or folder images are DOS independent and therefore are available under different DOSes.


AspeQt as of v0.8.5  no longer supports ApeTime (Date/Time downloader utility) from the AtariMax APE package. The support code has been removed from the source. Please use AspeCl for Date/Time download and other remote functionality.

Original AspeQt code up to version 0.6 Copyright (2010), Fatih Aygün

Updates since version 0.6 Copyright (2012), Ray Ataergin (

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