Kickstart (Amiga)

Kickstart is the bootstrap firmware of the Amiga computers developed by Commodore.

Most Amiga models were shipped with the Kickstart firmware stored on ROM chips. Its purpose is to initialize the Amiga hardware and core components of AmigaOS and then attempt to boot from a bootable volume, such as a floppy disk.

Commodore's AmigaOS was formed of both the Kickstart firmware and a software component provided on disk (with the software portion often termed as Workbench). For most AmigaOS updates the Kickstart version number was matched to the Workbench version number. Confusingly, Commodore also used internal revision numbers for Kickstart chips. For example, there were several Kickstart revisions designated as version 2.0.

The first Amiga model, the A1000, required that Kickstart 1.x be loaded from floppy disk into a 256 KB section of RAM called the writable control store (WCS). Some A1000 software titles (notably Dragon's Lair) provided an alternative code-base in order to use the extra 256 KB for data. Later Amiga models had Kickstart embedded in a ROM chip, thus improving boot times. Many Amiga 1000 computer were modified to take these chips.

Kickstart was stored in 256 KB ROM chips for releases prior to AmigaOS 2.0. Later releases used 512 KB ROM chips containing additional and improved functionality. The Amiga CD32 featured a 1 MB ROM (Kickstart 3.1) with additional firmware and an integrated file system for CD-ROM.

Early A3000 models were, like the A1000, also shipped with Kickstart on floppy disk, and used a 1.4 BETA ROM as bootstrap. Either Kickstart 1.3 or 2.0 could be extracted to a partition specifically named WB_1.3 or WB_2.x, respectively, and put in DEVS:kickstart, an absolute system location from where the A3000 system will find it at bootstrap and copy its image into RAM. This early A3000 supported both ROM based Kickstarts and disk-based Kickstarts, although not simultaneously. An A3000 configured to use disk-based Kickstart images had the benefit of being able to boot various versions of AmigaOS without additional tools, simply by selecting the appropriate Kickstart image at boot time.

...
Wikipedia