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The Amiga computers such as the Amiga 1000 required a Kickstart floppy to be able to boot directly into a hard drive. I have a Amiga 1000 as well but missing the Kickstart floppy. I would like to access the hard drive for my personal use with the floppy without damaging any of the internals of the Amiga 1000.

How can I safely and effectively boot directly to the hard drive with an Amiga 1000 without the necessary Kickstart floppy?

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You need a Kickstart ROM adapter to eliminate the need for the Kickstart disk. There are a number of such adapters out there such as this one that's currently in production.

And to boot to a hard drive, you will need a Kickstart 1.3 (or greater) ROM (I think the linked one will work).

Then you can boot to a SCSI hard drive.

I should also mention the ACA500 accelerator which includes Kickstart 1.3 and 3.1 (no Kickstart adapter necessary) and two CompactFlash slots which replace a hard drive. Here is a video showing it connected to the Amiga 1000, with another accelerator plugged into it.

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The previous answer is definitely the correct one, however, theoretically and with enough time, the A1000's boot ROM could be reworked to pilot your hard drive controller, interpret the Rigid Disk Block structure on the HD and eventually load a Kickstart either from a file with a filesystem (that would also require a small read-only OFS/FFS driver) or from a special partition. Then you would enable the Write Control Store and reset to the loaded Kickstart.

AFAIK, the original A1000 ROM code is a 8KB but the ROM chips themselves are two 8bit x 32K locations, so there is 64KB of space available.

I'm not aware of anyone that ever tried this way, however, not even back in the days when Commodore was alive.

EDIT:

Further expanding what I wrote, as it may be a bit more complicate that "just" talking to the chip and reading data from disk.

A potential hurdle could be bringing the HDD controller to life... investigation would be needed to see if the AutoConfig protocol can be activated on the controller in such an early environment (to be sure the controller card initializes itself so that the controller chip can be acted upon) and still end in a state where the next reset would reinitialize it. Indeed, assuming A1000 hard drive cards even had AutoConfig!

It may be easier if the controller did not use AutoConfig, but then more investigation would be needed to understand where the controller maps itself in the address space.

In any case code in the eventual controller's ROM would probably not be useful as it would assume Exec running and if an autobooting one, that it is called via AmigaDOS's boot protocol.

  • For clarity, you're suggesting theoretically replacing the boot ROM with one that has a minimal driver to load the Kickstart from the HDD? If so that should theoretically be possible, although the boot ROM would have to be specifically coded to match the type of HDD controller being used, or sophisticated enough to detect the HDD controller and respond accordingly, correct? – mnem Aug 4 '16 at 20:06
  • Yes, that could be a fun, challenging project. Especially the "fit it in 64KB of ROM" part. Back in the day it probably would have been easier and better for the manufacturer of the HDD controller to supply a modified boot ROM that specifically matched their product rather than a universal type one that detected which type of controller was present. It could have been used as a sales feature to differentiate their product. The biggest hurdle would probably be getting permission to include the Kickstart files on the HDD as shipped, since user installation would be non-trivial. – mnem Aug 5 '16 at 17:52
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    There is at least one controller for A1000 that implemented Kickstart and Workbench autobooting back in the days. That could be done because the very first thing the A1000 boot ROM does is check for a magic value (IIRC: 0x1111) at the start of the "Cardrige ROM" area (IIRC: 0xF00000), and jump there if it finds the magic value, much like what Kickstart itself does as the very first operation. So the HDD controller board had a ROM mapped at that address with custom code to locate (straight on the FileSystem?) and load a Kickstart file from the hard disk. – user180940 Aug 11 '16 at 8:04

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