39 votes
Accepted

What's the most recent version of AmigaOS?

A simple question, with a surprisingly complex answer... Really TL;DR Hyperion released Hotfix 3.2.2.1 on April 23, 2023 TL;DR The latest version of each of the main derivates of AmigaOS are: Branch ...
Richard Downer's user avatar
30 votes
Accepted

Why do Amiga Libraries have negative entry points?

TL;DR: What functionality or convenience is gained by having these offsets be negative values from the base address? It provided easy access to two lists that can be extended independently in future ...
Raffzahn's user avatar
  • 223k
20 votes
Accepted

How does the Kickstart ROM load and start workbench?

The Amiga Kickstart ROM is made up of numerous modules, libraries, and device drivers. One of the modules is Strap, as in Bootstrap. After I/O and expansion devices have been enumerated and ...
Brian H's user avatar
  • 60.8k
19 votes
Accepted

How are Amiga libraries structured?

A library in Amiga programming is exactly as you describe - you obtain a pointer to the library base address, and then call a function by loading the library base address into A6, the required ...
Richard Downer's user avatar
15 votes
Accepted

How Amiga A590 autoboot ROM and bootable floppy disk works?

In order to autoboot any Amiga hard disk, 3 things are needed. A version of Kickstart that supports boot from HD. This means >= Kickstart 1.3. A device driver that knows how to speak to the HD ...
Brian H's user avatar
  • 60.8k
15 votes
Accepted

AmigaOS 3.9 - where can I buy it?

You probably can't buy AmigaOS 3.9 any more. For a time, various Amiga retailers had stock of the physical AmigaOS 3.9 CD-ROM - the only format it was available in - but it would seem to have sold out....
Richard Downer's user avatar
14 votes

Was there ever a Kickstart that took advantage of 68020+ instructions that would work on an A2000?

The AmigaOS had a pretty small and specific set of features to allow the system to easily adapt to upgraded CPU's, either shipped in upgraded systems from Commodore, or added to the system using ...
Brian H's user avatar
  • 60.8k
14 votes
Accepted

What does it mean to byte swap or split a ROM image?

Splitting the ROM is not the same as byte-swapping the ROM. Amiga ROMs are usually split so that odd locations and even locations are stored in separate chips. This is because the 68000 has a 16-bit ...
Omar and Lorraine's user avatar
12 votes
Accepted

What advantages are there to replacing Kickstart 3.0 with Kickstart 3.1?

Kickstart 3.1 can detect some memory expansions automatically so that AddMem is not needed in your startup sequence, and it has a few other improvements that are required for Workbench (AmigaOS) 3.5 ...
snips-n-snails's user avatar
12 votes
Accepted

Extended ROMs on the Amiga CD32 and CDTV

With the information in pndc's answer to this question I've been able to examine the various ROMs and I think I have the definitive answer. Firstly it seems that CDTV and CD32 do things slightly ...
Richard Downer's user avatar
12 votes

What options were available for having an Amiga 1000 not be dependent on a KickStart disk?

TL;DR You will need to open up the machine to see exactly what kind of Kickstart ROM upgrade is installed. As you are probably aware, the disk-based Kickstart boot floppy was not part of the original ...
Brian H's user avatar
  • 60.8k
11 votes

How are Amiga Kickstart Relocation Files (.RTB) created?

The job is non-trivial, but I don't think it would be hard for someone 'experienced in the art'. 256k or even 512k is not a lot of code, and the ROMs are highly structured with a well-defined ...
Bruce Abbott's user avatar
  • 6,673
10 votes
Accepted

Any Issues with running Workbench 1.3 on a Kickstart 1.2 Amiga 500?

No, you can and, more importantly, it is fully supported to run Workbench 1.3 on a Kickstart 1.2 machine. This was rather common back at that time, because Workbench 1.3 brought some nice new ...
user180940's user avatar
  • 3,716
10 votes

How are Amiga libraries structured?

@RichardDowner has already answered it, but who don't want pictures? 🤖 These are from the Amiga ROM Kernel Reference Manual: Libraries, 3rd edition, @1992 by Commodore Electronics, Ltd. What Every ...
RichF's user avatar
  • 9,336
9 votes

Extended ROMs on the Amiga CD32 and CDTV

There are a number of ways that an extension ROM can add to or replace Kickstart functionality: Within the first few instructions, Kickstart checks for the magic value 0x1111 at 0xf00000, and will ...
pndc's user avatar
  • 11.3k
9 votes
Accepted

How did the Amiga 1000 WCS (write controlled store) for Kickstart work?

I have disassembled the A1000 boot ROM to see how it works. The boot ROM is linked to address 0xf80000, and the WCS appears as RAM at 0xfc0000 through 0xffffff. When the boot ROM is satisfied that ...
pndc's user avatar
  • 11.3k
9 votes
Accepted

Was there ever a Kickstart that took advantage of 68020+ instructions that would work on an A2000?

Cloanto maintain a list of known Amiga ROMs, a few of which require a 68020 or even a 68020 + MMU. The associated FAQ suggests that some A3000 ROMs use 68030-MMU-specific instructions. The Amiga ...
Stephen Kitt's user avatar
8 votes

How does the Kickstart ROM load and start workbench?

Your opening statement is only partly correct: As I understand, on the Commodore Amigas, the kickstart copies itself into a region of memory which is later made read-only. This is true for the ...
Richard Downer's user avatar
8 votes

What is the minimum set of Kickstart kernel modules to allow an Amiga to boot?

Because the Amiga is so flexible in its use of system software, what you hope to accomplish here becomes really pertinent. Obviously, doing anything useful is going to require the creation of a Task (...
Brian H's user avatar
  • 60.8k
8 votes
Accepted

How are Amiga Kickstart Relocation Files (.RTB) created?

I finally had to bite the bullet and do the exercise to create a .RTB of a ROM file which didn't have one: the old A1000 1.1 ROM (v31.34) Bruce Abott answer is spot on on most parts, but devil is in ...
Jean-François Fabre's user avatar
8 votes
Accepted

What is the purpose of ROM switcher mods in CDTV

I've seen a lot of information on CDTV ROM switchers, but it is still unclear to me what is the actual purpose of it. The CDTV is essentially an Amiga 500 sans keyboard and floppy but with CD and ...
Raffzahn's user avatar
  • 223k
8 votes

What does it mean to byte swap or split a ROM image?

I'm not familiar with Amiga specifically, but, in the general case as you'd see with something like tools for manipulating ROMs of console cartridges: The system being dumped will typically return ...
ssokolow's user avatar
  • 6,765
7 votes
Accepted

How to integrate an 512kB EEPROM on a A3660 accelerator board at $00F00000?

The Amiga Kickstart ROM is modular. As such, you can build custom ROM images containing whatever selection of libraries, devices, and handlers you would like to be ROM resident. And, as you indicated, ...
Brian H's user avatar
  • 60.8k
7 votes
Accepted

What options were available for having an Amiga 1000 not be dependent on a KickStart disk?

Here are some options for booting an Amiga 1000 without a physical Kickstart floppy disk: Kickstart eliminators: CMI Kickstart Eliminator DKB KwikStart and KwikStart II Kupke Kickstart Modul Rex ...
6 votes

Extended ROMs on the Amiga CD32 and CDTV

Apart from other version-related changes, there is a notable functional difference between the CDTV extended ROM and the A570 extended ROM: for some reason, perhaps related to the fact that the A570 ...
mike's user avatar
  • 436
5 votes
Accepted

How do I detect if AmigaDOS dos.library/CurrentDir() fails?

The only thing CurrentDir() does is change the lock in your process structure that is used as the process' current directory, and return the old value. So, it is the return value of Lock() applied to ...
Brian H's user avatar
  • 60.8k
4 votes

What exactly are the differences between Kickstart 1.2 and 1.3?

Kickstart 1.3 changed the file system to avoid extra disk space waste "due to the fact it could store only 488 bytes in any block of 512 bytes keeping 24 bytes for checksums."1 1.3 also added a new ...
JAL's user avatar
  • 9,502
4 votes

What is the minimum set of Kickstart kernel modules to allow an Amiga to boot?

Original Amiga 1000 was loading the kickstart from the floppy disk. There were even games that doesn't require Kickstart. From there I understand, there is no need for kickstart modules to start the ...
wizofwor's user avatar
  • 2,788
4 votes

What advantages are there to replacing Kickstart 3.0 with Kickstart 3.1?

OS-wise, Kickstart 3.1 should have more optimized graphics.library routines (rewritten to assembler), and some more tags for VideoControl() to speed up remaking the display in some cases (eg. do not ...
user180940's user avatar
  • 3,716
4 votes

What advantages are there to replacing Kickstart 3.0 with Kickstart 3.1?

You need the 3.1 ROM if you want to use OS3.9, and more importantly OS3.9's support for the use of larger than 4GB of HDD space by the Amiga OS. Without 3.1 ROM and OS3.9 you can still use larger ...
mnem's user avatar
  • 4,537

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