Table of Contents
Kickstart
Kickstart refers to the essential parts of the AmigaOS operating system that are usually located in the ROM. Kickstart contains, among other things, the exec.library (the kernel), the dos.library (the DOS), the graphics.library and the intuition.library (the system libraries for the Amiga GUI).
Versions 1.0 and 1.1 from 1985 were only delivered with the Amiga 1000, originally in the form of a bootstrap disk that was loaded into a special RAM area (WOM), which was protected against overwriting after loading and could therefore only be read until the next cold boot. Version 1.2 from 1986 was introduced with the Amiga 500 and the Amiga 2000, the successor models to the Amiga 1000. On these models, Kickstart was no longer laboriously loaded from a floppy disk, but replaced by a permanently installed ROM. This shortened the boot time enormously. The disadvantage, however, was that you had to open the computer and replace the module to update to a new Kickstart version. Up to this point, Kickstart fitted into a ROM with a size of 256 KiB.
Later Kickstart versions were supplemented with device drivers for ATA, SCSI and PCMCIA hardware, among others. From version 2.0, which was delivered with the Amiga 3000 and from version 2.04 also with the Amiga 500+, a larger ROM was therefore necessary, which now had a capacity of 512 KiB.
From version 2.0, the disk validator, which was previously loaded dynamically from diskette, has also been integrated into the ROM. This becomes active if a floppy disk is inserted where write operations have not been completed.
On a standard Amiga, Kickstart can be found in the memory addresses 0xFC0000 or 0xF80000 to 0xFFFFFF. However, this area is not hard-coded in the operating system, which is exploited by so-called soft kickers that can start Amigas with a different Kickstart version, whereby this is loaded at a different address and its jump addresses are modified for this purpose.
AmigaOS 4, which was released in 2006, still uses the original architecture, but the kickstart modules are now located on the boot disk, from which they are activated by the boot loader.
Versions
However, the respective version of Kickstart is not displayed in the system with the known version number. If you enter the Version command in the shell, the system returns Kickstart 40.63, Workbench 40.42, for example. This means that OS 3.1 is running on this machine.
Versions 1.2 to 3.2 are generally downward compatible with their predecessors.
All Amiga models except the Amiga 1000 can accept Kickstart ROMs. It is also possible to load Kickstart via software (rekick, softkick). Kickstart must contain drivers for the hardware of the target machine, otherwise some extensions cannot be used (e.g. IDE controller, PCMCIA port, SCSI port).
The different versions are listed on the overview page.
Boot Screen
The highly symbolic image, which prompted users to insert the Workbench floppy up to and including version 1.3, shows a left hand and a blue floppy disk. The lettering “Amiga Workbench” is upside down. In versions 1.2 and 1.3, the version is displayed below the floppy disk, before this version information was missing on the boot screen.
The fact that the graphic quality of this so important image of the Amiga was far below its technical possibilities is explained by the severely limited memory volume in the A1000 boot ROM. The graphic is also not stored as a bitmap, but in 412 bytes as a vector graphic in an array, which is mainly converted into two commands (line drawing and coloring).
