OS-9 Frequently Asked Questions

Updated February 7, 1998



What is OS-9?

OS-9 is a real-time, multiuser, multitasking operating system developed by Microware Systems Corporation. It provides synchronization and mutual exclusion primitives in the form of events, which are similar to semaphores. It also allows communication between processes in the form of named and unnamed pipes, as well as shared memory in the form of data modules.

OS-9 is modular, allowing new devices to be added to the system simply by writing new device drivers, or if a similar device already exists, by simply creating a new device descriptor. All I/O devices can be treated as files, which unifies the I/O system. In addition, the kernel and all user programs are ROMable. Thus, OS-9 can run on any 680x0 based hardware platform from simple diskless embedded control systems to large multiuser minicomputers.

Originally developed for the 6809 microprocessor, OS-9 was a joint effort between Microware and Motorola. The original version of OS-9 (OS-9 Level I) was capable of addressing 64 kilobytes of memory. OS-9 Level II took advantage of dynamic address translation hardware, and allowed a mapped address space of one megabyte on most systems, and up to two megabytes on others, most notably the Tandy Color Computer 3.

In the 1980's, Microware ported OS-9 to the 68000 family of microprocessors, creating OS-9/68000, which is used in a variety of industrial and commercial arenas, including Philips' CD-i and most recently, set-top boxes for interactive television.


What is OS-9000?

OS-9000 is a portable version of OS-9, written primarily in C. It is available for the Intel (386 and higher) and PowerPC processors. Code is portable across OS-9000 platforms and between OS-9 at the source code level. Theoretically , OS-9000 can be ported to any modern computer architecture.


What is DAVID?

DAVID is a configuration of OS-9/OS-9000 targeted towards the Interactive TV Set Top Box (STB) market. DAVID stands for Digital Audio Video Interactive Decoder. The unique characteristics of DAVID are that it will always include the following I/O subsystems:

Like all OS-9 systems, DAVID may be expanded with any other file managers, but these are considered the base case set.

DAVID is being shipped for 68xxx, Power PC and 80x86 processor families. Click here for more information on DAVID.


What machines run OS-9?

OS-9 runs on a multitude of machines, from set-top boxes to industrial control machines. Some of the more well-known platforms include the GMX EISA, Atari ST, Commodore Amiga, Apple Macintosh and a large number of 680x0-based VME systems manufactured by such companies as Radstone Technology, Motorola, Heurikon, Inducom, Force, Mizar, ELSOFT, Eltec, PEP Modular Computers, and others. Gespac also makes a large number of platforms based on their G-64 and G-96 bus.

OS-9/6809 runs on a variety of platforms, perhaps the most (in)famous being the Tandy Color Computer. Other systems include the SWTPC SCB-69, the Gimix 6809, Smoke Signal Broadcasting's Chieftain 6809, FHL's TC-9, the Febe, and a host of others, most of which are SS-50 bus machines. Note that OS-9/6809 is no longer supported by Microware, but many user groups, BBSes, and a handful of FTP sites offer help and maintain software collections for OS-9/6809.


What software is available for OS-9?

OS-9 software can be found either commercially or in the public domain/shareware/freeware. The most notable place to obtain free OS-9 software and code examples is through Real-Time Services Inc.'s free OS-9 ftp site at ftp://os9archive.rtsi.com. There is a considerable amount of "legacy" applications such as word processors, spread-sheets and utilities which are mostly not used anymore since OS-9's focus has changed almost exclusively to that of an embedded, real-time operating system.


Where can I get OS-9?

Generally, a hardware vendor of a particular computer system will ship a version of OS-9 for their platform. In addition, several software vendors sell customized and enhanced OS-9 packages, and Microware sells single license copies for certain systems.


What development tools are available for OS-9?

Microware sells FasTrak, a host/target development system consisting of a GUI based debugger, profiler and Ultra C++ compiler. FasTrak is available for Windows 95/NT or UNIX based platforms and supports user- and system-level debugging. Development is typically done with the OS-9 target connected to the host development machine via ethernet or SLIP. FasTrak for Windows 95/NT based platforms also comes with the Codewright programmer's editor.

CodeWarrior, from MetroWerks, is another GUI based development environment for OS-9 development. Unlike FasTrak, CodeWarrior is only available for Windows 95/NT and does not support system-level debugging.


Does OS-9 have TCP/IP support?

Yes. Microware sells LAN Communications Pak, which is a complete TCP/IP package based on the SPF file manager. LAN Comm Pak includes telnet and ftp client and server applications. Its performance is considerably better than that of Microware's older TCP/IP support package, ISP. LAN Comm Pak also provides a C BSD 4.2 compatible socket library, as well as SLIP and PPP client support.

Additionally, there is a port of the Phil Karn ka9q internet software package, which supports a single-user interface to TCP/IP. It includes a telnet client, an FTP client and server, and SMTP. Source and executables may be found on ftp://os9archive.rtsi.com.


Does OS-9 properly handle Y2K (Year 2000)?

Yes, as of OS-9/68000 version 3.0.3. Previous versions of OS-9/68000 do not handle the Y2K problem correclty. Specifically, some utilities cannot interpret Y2K properly, and some clock modules may also be at fault. Contact Microware for details on upgrading to OS-9/68000 3.0.3.

OS-9000 handles Y2K properly; therefore, upgrading is not necessary.


What communications software is available?

Several public domain programs are available from os9archive including terminal emulators and file transfer utilities. Sterm, a popular non-commercial package, can run on any terminal based OS-9 system and supports XModem as well as Compuserve B+ protocol. In addition, many software vendors sell various equivalent packages. C-Kermit is available in source and executable form for OS-9.

If you are looking for X/Y/ZModem and kermit protocols, an excellent implementation by Tim Kientzle can be found on ftp://os9archive.rtsi.com.


Is GCC available for OS-9?

GCC and g++ are available for OS-9/68000, both in OS-9 executable form and cross-compiler form. Version 1.37 was ported to OS-9 by Atsushi Seyama and was then supported and updated to the version 1.39, 1.40, and 1.42.2 by Stephan Paschedag. Source and binaries are available on ftp://os9archive.rtsi.com . The 1.40 versions and up support 68040 optimizations. Version 2.x of GCC is a completely new port to OS-9 which allows better optimization. The first version that was released was version 2.4.5.

The current edition includes a new I/O library which gives full compatibility with C++ programs (I/O streams). It also supports the different calling interfaces of Microware's compilers (K&R C V3.2 and Ultra C). Bear in mind that the newer editions (2.x) will require at least 4 MB of memory free in order to run.


What graphics interfaces are available?

There are several to choose from. Microware has MAUI, the graphical environment which is currently being used in DAVID set-top boxes.

Microware also sells a port of X11R5 (client and server plus optional Motif). Eltec Electronik GmbH sells ports of X11R4, X11R5 and X11R6. Kei Thomsen has also done a port of X11R5 and X11R6. His port requires Microware sockets, GCC 2.x, OS9lib.l (unix compatibility routines), and a bourne shell for running imake. It requires a minimum of 4 MB physical memory, 8MB if you plan to run any applications.

Several other companies have various graphics packages for OS-9. MGR, the window manager from Bellcore, is available for the WCP306 computer, and Reccoware Systems also has a port. Gespac produces G-Windows, a portable windowing package which has device windows and a very Motif-looking interface. For the MM/1, BlackHawk Enterprises sells K-Windows, a window manager similar to the Multi-Vue OS-9 window package for the Tandy Color Computer 3.


Where can I obtain public domain software for OS-9?

Public domain software for OS-9 can be found on the Internet, as well as on several bulletin boards dedicated to OS-9. The primary Internet resource for public domain software is os9archive.rtsi.com. This ftp site contains a large amount of OS-9/68000 and OS-9/6X09 software contributed by many individuals. Some OS-9 software can also be found on wuarchive.wustl.edu. Another ftp site in located in Europe is lucy.ifi.unibas.ch.

For Color Computer OS-9 users, there is the Princeton Listserver, which acts as a mailing server that will mail requested software. To begin using the Listserver, send electronic mail to listserv@pucc.princeton.edu, with the word HELP in your message.

os9archive.rtsi.com contains mostly OS-9/68000 software, including the complete TOP package, many EFFO disks, GCC and G++, (and many other GNU products such as flex and bison), ka9q, k5jb, TeX, LaTeX, and quite a bit of 6809 software.


What is the TOP package?

TOP is an acronym for "The OS-9 Project". It is a collection of OS-9/68000 software developed primarily in Germany and available on ftp://os9archive.rtsi.com. Much of it seems to be an attempt to make OS-9 a little more UNIX-like. Many standard UNIX utilities are provided, as well as a complete UUCP mail implementation, and a more secure password file and login program. Many traditional UNIX games are also provided. The total package consumes approximately 16 MB of disk space, though much of this is source code.


What books are available that cover OS-9 topics?

Here is a listing of currently available books dealing with OS-9 topics.


Are there alternative shells for OS-9?

Yes, there are. Microware sells MShell, an enhanced shell. In addition, there are several public domain shells available. The most notable of which is the Bourne shell, sh, available in the TOP package (OS-9/68000) in its original version. A newer version with may enhancements and bug fixes is available through EFFO. sh supports aliasing, command-line editing, history, environment variable replacement, shell scripting, the `command` operator (which uses the output of the command as arguments to the called program), and a startup file. For users feeling at home in a VAX/VMS surrounding, the zsh shell is commercially available from ELSOFT.

A PD version of ksh is available on ftp://os9archive.rtsi.com. Bash, the GNU shell, has also recently been ported. Bash is also available on os9archive.

For OS-9/6809, there is Shell+ and if you have a Color Computer 3, there is always GShell a graphical shell.


Can one read/write MS-DOS format disks under OS-9?

Yes, there are several public domain and commercially avaliable utilities to accomplish this task, for both OS-9/6809 and OSK. One of the more interesting is the MSFM file manager which appears in OS-9 Insights, a book by Peter Dibble, available through Microware. MSFM is an actual file manager, which allows you to mount an MS-DOS floppy as part of the OS-9 file system. PCF, available from Microware, is an updated file manager which also reads and writes MS-DOS format disks.


Can one read/write OS-9 format disks on a PC?

Yes, there is a product called OS9MAX which is capable of managing OS-9 media such as diskettes, hard disks, pcmcia memory chip cards, PC cards, CD-ROMS and other OS-9 RBF style devices. OS9MAX lets you read, write amd format OS-9 disks on a PC.

Contact DTR Datentechnik Reischke for more information.

DTR also has software which will allow backup from OS-9 to CD-ROM. It requires Microware's ISP and a PC CD-ROM recorder.


Where can I get online information about OS-9?

There are several newsgroups and mailing lists on the internet which discuss OS-9 and its derivatives. On Usenet NetNews, the following groups cover OS-9, the first of which more so than the others:

CompuServe and Delphi both have OS-9 forums with a files section for downloads of some of the latest OS-9/68000 and OS-9/6809 shareware. On-line conferences are regularly scheduled on Delphi's OS-9 forum on a variety of topics. GEnie also has OS-9 support with OSK files found in a section of the Atari ST RoundTable and CoCo OS-9 and MM/1 files found in the Tandy RoundTable.

Also, the Princeton Listserver carries a discussion forum for the Tandy Color Computer and its derivatives, which often includes discussion of OS-9/6809. To get information about the listserver, send e-mail to listserv@pucc.princeton.edu, with the word HELP as the body of the message.


What about UUCP and news?

Several ports of UUCP software are available for both OS-9/6809 and OS-9/68K. A port of C news and RN are available on os9archive.rtsi.com. TOP has ported Notes, which maintains Notesfiles. There is a program which will transfer between Notesfiles and netnews. The TOP package in its entirety may be found on os9archive.

Rick Adams' UUCP port for OS-9/6809 is also available, and this has been updated to UUCPbb by Bob Billson, Boisy G. Pitre and others. UUCPbb is also available for OS-9/68000 and may be found on wuarchive and os9archive, as well as on Delphi and CompuServe. A nice companion mail reader for this package called Palm, which has Elm-like features, is also available.

  • UUCPbb features:
  • Elm has also been ported to OSK, and is available on os9archive. The Elm package is a port of elm 2.4; it fits in the rmail/lmail/uucp environment that can be found in the TOP package.

  • Elm features:
  • For more information on Elm, contact Harold Groene.


    Where do I get OS-9/68000 for the Commodore Amiga?

    Digby Tarvin from Australia, has a port of OS-9/68000 for the Amiga, which costs approximately $600 US.


    What is a Real Time system?

    A real-time system is any system whose correctness depends not only on the correctness of the applied algorithms, but also in the timing of the execution of those algorithms. Refer to the newsgroup comp.realtime for more information.


    Does OS-9 support multiple threads within a program?

    No, not directly like Mach does, but through the use of user installed periodic interrupts or alarms, a user program can support its own threads. Consult a good operating systems book for more details.


    The OS-9 FAQ WWW Page is currently maintained by Boisy G. Pitre. Please send any changes or corrections to boisy@pitretech.com