AmigaOS facts for kids
Screenshot of AmigaOS 4.1
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| Company / developer | Commodore International, Hyperion Entertainment |
|---|---|
| Programmed in | Assembly language, BCPL, C |
| OS family | Amiga |
| Working state | Current |
| Source model | Closed source |
| Initial release | July 23, 1985 |
| Latest stable release | 4.1 Final Edition Update 2 / January 12, 2021 |
| Supported platforms | M68K: versions 1.0 through 3.9 PowerPC: versions 4.0 through 4.1 |
| Kernel type | Microkernel |
| Default user interface | Graphical (Workbench) |
| License | Proprietary |
AmigaOS is a special computer operating system made for Amiga and AmigaOne personal computers. It was first created by Commodore International and came out in 1985 with the first Amiga computer, the Amiga 1000.
Older versions of AmigaOS needed a type of computer chip called the Motorola 68000 series. Newer versions were made by other companies like Haage & Partner and Hyperion Entertainment. The very latest version, AmigaOS 4, needs a different type of chip called a PowerPC.
AmigaOS is a system where one person uses the computer at a time. It's built around a core program called Exec. This core program lets the computer do many things at once, even if it looks like it's only doing one thing.
The operating system includes several important parts:
- A way to talk to the Amiga's hardware.
- A system for managing files and disks called AmigaDOS.
- A system for creating windows and graphics called Intuition.
- A desktop screen and file organizer called Workbench.
The rights to AmigaOS are shared among a few companies. In 2001, Amiga Inc. asked Hyperion Entertainment to develop AmigaOS 4. Later, Hyperion got a special license to keep making AmigaOS 4 and future versions.
In 2015, the secret instructions (called source code) for AmigaOS 3.1 were shared online. Hyperion Entertainment confirmed this happened.
Contents
What are the main parts of AmigaOS?
AmigaOS is made up of two main parts:
- Kickstart: This is like the computer's starting instructions, usually stored in a special memory chip (ROM).
- Workbench: This is the software part you see and use, like the desktop and file manager.
Until AmigaOS 3.1, Kickstart and Workbench were released together. But after that, mostly only the Workbench software was updated.
Kickstart: The Computer's Startup Guide
Kickstart is the special program that helps the Amiga computer start up. It's usually stored in a ROM chip. Kickstart has the basic code needed to get the Amiga hardware working and loads many important parts of AmigaOS.
You can think of Kickstart like the BIOS in a regular PC. But Kickstart does even more! It can even start up the full windowing system right away.
When you turn on or restart an Amiga, Kickstart checks the system. Then it gets the Amiga's special chips and some core OS parts ready. After that, it looks for a place to start the computer, like a floppy disk or hard drive. If it can't find one, it asks you to put in a disk.
Kickstart reads the first part of a disk (called the bootblock) to start the system. Some old games and demos used their own bootblocks. This allowed them to take over the computer and run without needing the full AmigaOS.
Sometimes, computer viruses would target these bootblocks. They would replace the original code, stopping games or demos from working. Anti-virus programs tried to fix this by adding their own bootblocks to check for viruses.
Exec: The Multitasking Brain
Exec is the core part of AmigaOS that handles multitasking. This means it lets the computer run many programs at the same time. Exec also manages the computer's memory, handles special signals (interrupts), and works with shared program parts (dynamic libraries).
Exec acts like a manager, deciding which program gets to use the computer's processor next. It uses a system where programs take turns, but important programs get more turns.
Exec also helps different programs talk to each other by sending messages. Because Amiga computers have a simple memory setup, sending these messages is very fast and efficient.
AmigaDOS: Managing Files and Commands
AmigaDOS is the part of AmigaOS that handles everything to do with disks and files. This includes:
- Organizing files and folders.
- Letting you use text commands to control the computer (like typing instructions).
- Sending commands to different places.
- Running scripts (small programs that automate tasks).
In the very first AmigaOS versions (1.x), AmigaDOS was based on an older programming language called BCPL. This made it a bit tricky to use with other languages.
From AmigaOS 2.x onwards, AmigaDOS was rewritten using C and Assembler. This made it faster and easier to use, while still working with older programs.
AmigaOS 4.1 even updated AmigaDOS to work with newer, more powerful 64-bit computer systems.
AmigaOS often uses file extensions (like .txt or .jpg), but they aren't strictly needed. The system knows what a program is by a special code inside the file.
Intuition: The Graphical Look
The Amiga's main windowing system is called Intuition. It handles what you see on the screen, like windows, menus, and buttons. It also manages your mouse and keyboard input.
Before AmigaOS 2.0, every program had to create its own buttons and menus. This meant that different programs looked very different. With AmigaOS 2.0, new tools were added to help developers make programs that looked and felt similar. Commodore also released a guide to help everyone design programs in a consistent way.
A cool feature of AmigaOS is that it can show many different "screens" on the same display. Each screen can have its own resolution or number of colors. AmigaOS 2.0 also let programs share their screens with other programs. You could switch between these screens by clicking a small button in the corner.
Workbench: Your Digital Desk
Workbench is the main graphical program that helps you manage your files and desktop in AmigaOS. The name "Workbench" suggests a workspace, like a real workbench.
- Folders are called drawers.
- Programs are called tools.
- Data files are called projects.
- Buttons and widgets are called gadgets.
The Workbench desktop looks a bit like the old Mac OS desktop. It shows icons for disks and hard drives. There's also a single menu bar at the top of every screen. The standard Amiga mouse has two buttons. The right button is used for pull-down menus.
Cool Features of AmigaOS
Graphics: Bringing Images to Life
Early versions of AmigaOS worked directly with the Amiga's own special graphics chips. This allowed for cool effects like sprites and raster graphics.
Later, people made special systems called retargetable graphics (RTG). These allowed AmigaOS to work with other graphics cards, not just the original Amiga ones. This meant Amiga computers could use more modern display hardware.
The Amiga didn't have built-in 3D graphics, but it became a very popular platform for creating 3D art and animations. Programs like Lightwave (used for TV shows like Babylon 5) were famous on the Amiga.
The Amiga was also great at working with video. It could easily connect to video equipment (called genlock). Many companies made special hardware for the Amiga to capture video, like Newtek's Video Toaster.
Newer versions of AmigaOS, like AmigaOS 4.1, use modern 3D features to make the desktop look smoother and more advanced.
Audio: Sounds and Speech
Older AmigaOS versions used the Amiga's special sound chip. This chip could play sounds using four channels.
Later, a standard called AHI was created. This allowed AmigaOS to work with other sound cards and play sounds more smoothly. It also let programs record sound and mix many sound channels together, going beyond the original four-channel limit.
AmigaOS was one of the first operating systems to have speech synthesis. This meant it could turn written text into spoken words in American English. There was a special program called Say that let you type text and have the computer speak it. This feature was sometimes used in educational software.
Storage: Saving Your Work
AmigaOS has a special type of RAM disk. This is like a super-fast temporary storage area in the computer's memory. It automatically changes size to fit what you put in it. Starting with AmigaOS 2.x, important system files were loaded into this RAM disk when the computer started. This made the system feel much faster.
There's also a special RAM disk called the RAD disk. This one can keep its contents even if you restart the computer softly. It could even be used to start the computer!
Scripting: Automating Tasks
AmigaOS has a powerful scripting language called ARexx (short for "Amiga Rexx"). This is like a special language that lets you control the entire operating system. It's similar to AppleScript on Mac computers.
ARexx lets programs talk to each other. For example, an ARexx script could tell an email program to save an email, then send it to another program to process it, and then open it in a viewer program. This makes it easy for different programs to work together.
Since AmigaOS 4, the Python programming language is also included with the operating system.
How AmigaOS Works (Technical Overview)=
AmigaOS is known for being very efficient. Even in 1996, a famous computer writer, John C. Dvorak, said it was one of the "great operating systems" because it could do many tasks at once using very little memory. He noted that even modern operating systems struggled to do what AmigaOS could do with just 1MB of memory.
Libraries and Devices
AmigaOS is built in a modular way, like building with LEGO bricks. It uses libraries which are like collections of functions that programs can use. These libraries are either stored on disk or in the Kickstart memory chip. This design makes it easy to update or change parts of the system.
Device drivers are also types of libraries. They help the computer talk to different hardware parts, like printers or hard drives.
Handlers, AmigaDOS, and Filesystems
A higher level of managing devices and resources is done by handlers. These are like small programs that communicate by sending messages. One type of handler is a filesystem handler. This means AmigaOS can use any type of file system, as long as a handler has been written for it. This allowed for new features like journaling (which helps prevent data loss).
Handlers often create a device name that you can use to access a piece of hardware. For example, DF0: usually means the first floppy drive. DH0: might be the first hard drive.
Filesystems also have volume names, which identify a specific disk. If your floppy disk is named "Workbench", you could use Workbench: to access files on it. So, to open a file called "MyDoc" in a folder called "Letters" on your "Workbench" disk, you could type "Workbench:Letters/MyDoc".
Programs often need to find files without knowing exactly where they are. This is solved using assigns. An assign is like a shortcut that points to a specific folder. For example:
- SYS: points to the main folder of your computer's startup drive.
- C: points to a folder with common commands you can type.
- DEVS: points to a folder with device drivers.
- LIBS: points to a folder with system libraries.
- S: points to a folder with scripts, including the special startup-sequence that runs when the computer starts.
- T: points to a temporary folder.
- PROGDIR: is a special assign that always points to the folder where the program you are currently running is located.
Memory Paging and Virtual Memory
AmigaOS 4 brought in new ways to manage the computer's RAM (memory). It can organize memory more efficiently and even use parts of your hard drive as a kind of virtual memory. This helps the computer run larger programs or more programs at once.
Different Versions of AmigaOS
Since 1985, AmigaOS has had several major updates. In the beginning, the entire operating system was called Workbench. But from version 3.5 onwards, the operating system was officially named "AmigaOS," and "Workbench" became just the name for the desktop part.
Workbench always let users change how it looked. You could change icons, their colors, and even where windows would open on the screen.
AmigaOS 1.0 – 1.4: The Beginning
AmigaOS 1.0 came out with the first Amiga 1000 in 1985. The 1.x versions usually had a blue and orange color scheme. This was chosen so it would look good even on older TV screens. You could change these colors if you wanted.
Users could also create their own icons, which could be any size and even have two different looks to make them seem animated when clicked.
AmigaOS 2.0, 2.1: A New Look
AmigaOS 2.0 came out with the Amiga 3000 in 1990. This version brought a more consistent look to programs. New tools helped developers make buttons and menus that looked the same across different applications.
AmigaOS 2.0 also added "public screens." This meant that programs could create their own screens that other programs could use, not just the main AmigaOS screen.
AmigaOS 2.1 added AmigaGuide, a simple system for online help files within programs. It also introduced Installer, a standard program for installing software.
AmigaOS 3.0, 3.1: More Features
Versions 3.0 and 3.1 came with the Amiga 1200 and Amiga 4000 computers. Version 3.0 added "datatypes." This allowed any program that supported datatypes to open many different kinds of files, like images or sounds, as long as the right datatype was installed. A small program called Multiview could open and show any supported file.
AmigaOS 3.5, 3.9: Updates After Commodore
About six years after AmigaOS 3.1, a company called Haage & Partner updated AmigaOS. These versions (3.5 and 3.9) were software updates for existing Amiga computers.
The look of AmigaOS was updated with new icons and support for more colors (24-bit color). These versions also included a new set of 256-color icons and desktop wallpapers, replacing the older gray look.
AmigaOS 3.9, released in 2000, added a program bar called AmiDock and improved system settings.
AmigaOS 3.1.4, 3.2: Modernizing the Classics
In 2018, Hyperion Entertainment released AmigaOS 3.1.4. This update brought many fixes and made parts of the system more modern. It also added support for larger hard drives and worked with all Motorola 680x0 CPUs. Unlike versions 3.5 and 3.9, it still supported the original Motorola 68000 CPU.
In 2021, Hyperion Entertainment released AmigaOS 3.2. This version included all the features of 3.1.4.1 and added new improvements like better support for graphical interfaces and managing Amiga Disk File images. Updates 3.2.1 and 3.2.2 followed with more fixes.
AmigaOS 4.0, 4.1: PowerPC Era
This new AmigaOS, called AmigaOS 4.0, was completely rewritten to work with PowerPC computer chips. It allowed users to drag windows in any direction and even drag icons between different screens.
AmigaOS 4.0 also included a new version of Amidock, support for modern fonts like TrueType, and a movie player that could play DivX and MPEG-4 videos.
AmigaOS 4.1 added new startup settings, updated icons for higher screen resolutions, new window themes, and an auto-update feature.
How AmigaOS Influenced Other Systems
AmigaOS had a big impact on how other operating systems were designed:
- AROS is an open-source operating system that tries to work like AmigaOS.
- MorphOS is another operating system for PowerPC computers that also works like AmigaOS.
- BeOS used a similar system to AmigaOS's "datatypes." This allowed the entire operating system to understand many different types of files (like text, music, videos) without each program needing to know how to open them all.
- AtheOS was inspired by AmigaOS and was originally meant to be a copy of it.
- Syllable is a newer operating system that came from AtheOS and has some features similar to AmigaOS.
- FriendUP is a cloud-based operating system that has many features inspired by AmigaOS, and some former Amiga developers work on it.
- The operating system for the 3DO Interactive Multiplayer game console looked a lot like AmigaOS. It was developed by RJ Mical, who also created the Amiga's Intuition user interface.
See Also
In Spanish: AmigaOS para niños
- Comparison of operating systems
