This is the native load address in memory for the beginning of the Kickstart ROM. Some ROM images can be relocated to other starting addresses with certain RAM-based kick tools if a suitable relocation table exists. The most common starting addresses are 0xFC0000 for 256K ROMs and 0xF80000 for 512K ROMs. The Amiga 1000 "Velvet" (pre-release) ROMs are located at 0xFE0000, and the Amiga 3000 "tower ROMs" are at 0xFF0000.
Many ROM images were made available to developers through CATS (Commodore-Amiga Technical Support) for the purpose of code testing (both Commodore's Kickstart code and application code). This was primarily to give professional software developers an early look at future AmigaDOS technologies. Despite having each developer or company having to sign a non-disclosure agreement, many of these developer images circulated around the Internet, prompting Commodore to later insert annoying yellow beta alerts into beta Kickstart images to try to further ward off illicit copying. The notes accompanying several of the hacked versions of these developer releases indicate this was not an effective deterrent.
Developer ROM images were often loaded with a Commodore-supplied tool called "KickIt" for the purpose of loading the image into RAM and adjusting boot-time pointers appropriately. Several other compatible tools can also be found on Aminet. A comprehensive list of alternate addresses follows:
0x200000 - Start of (true)fast RAM 0xC00000 - Start of pseudo-(slow)fast RAM (A500/A600 trapdoor) 0xF00000 - In-house Commodore RAM/ROM development/testing board