What exactly do newer AmigaOS releases need a 3.1 rom for?

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kyle_b

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Just sat here wondering about 3.9 and 3.1.4, both these are supposed to need a minimum of kickstart 3.1, but as anyone who's installed them knows, the first thing they do when you're on a 3.1 rom is load their own updated kickstarts into ram and reboot from that instead.

With that being the case, then why do they need 3.1? surely that'd work just as well on 3.0, 2.x, even an early 3000's Superkickstart?
 
kyle_b said:
Just sat here wondering about 3.9 and 3.1.4, both these are supposed to need a minimum of kickstart 3.1, but as anyone who's installed them knows, the first thing they do when you're on a 3.1 rom is load their own updated kickstarts into ram and reboot from that instead.

With that being the case, then why do they need 3.1? surely that'd work just as well on 3.0, 2.x, even an early 3000's Superkickstart?
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3.1 ROM was used as a stager ROM for the other AmigaOS’s.

For example AmigaOS 3.5 & 3.9 never had an official Replacement ROM set. Therefore you booted from 3.1 and a 3.9 Upgraded modules set was deployed in RAM to make use of these newer Operating scsi.device for bigger disks etc.

As for 3.1.4. Again 3.1 was the staging ROM. But you could burn the actual ROM files to EPROMs as well.

3.1 ROMs were a fail safe to allow you to install these newer Operating Systems. The same also goes for 3.2

It’s just a given that you now can burn and fit newer ROMs.
 
3.1 roms specifically have updated scsi drivers to have a 4GB limit, something that has been overhauled in 3.2 to have even larger hard drives.
3.2 goes up to 4TB.

Theoretical Limits: The underlying technology (TD64/NSD) supports exabytes, but RAM buffers are the real-world bottleneck.

So when doing this with PiStorm, the ram would not be an issue.

But your good for a 128GB SD card, that can easily be done with 32MB or 64MB.
And 3.2.2 allows for much larger start partition, I now have a 20GB start for Workbench and then for games, demos, programs and storage, these all have their separate partitions
 
Boing-ball said:
3.1 ROM was used as a stager ROM for the other AmigaOS’s.

For example AmigaOS 3.5 & 3.9 never had an official Replacement ROM set. Therefore you booted from 3.1 and a 3.9 Upgraded modules set was deployed in RAM to make use of these newer Operating scsi.device for bigger disks etc.

As for 3.1.4. Again 3.1 was the staging ROM. But you could burn the actual ROM files to EPROMs as well.

3.1 ROMs were a fail safe to allow you to install these newer Operating Systems. The same also goes for 3.2

It’s just a given that you now can burn and fit newer ROMs.
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I know that 3.1.4 (&3.2) can also use their own physical roms. The question is why having 3.1 rom chips is a hard requirement to softkick the newer ones, rather than letting you do it from any. What is supposed to be special about 3.1 that 3.0 does not provide?

Buzzfuzz mentions 3.1 allowing drives bigger than 4gb, but if that's the only reason then that's daft. Plenty of people don't use drives bigger than that on their Amigas. I'd rather just get a warning in the installer than to be told to fork out for new roms.
 
I think this is just coming down to semantics. When it comes to softkicking a full KS 3.2 ROM image, that should work just fine. i.e. 2.04 physical ROM chips and softkick 3.2. As long as your physical kickstart ROMs can find your boot partition and run it's startup-sequence and run the softkick program, I don't see why it wouldn't work.

Installing from scratch might be tricky, but again you could first manually softkick into 3.2 and then run the installer etc.

IIRC the typical happy path of physical 3.1 ROM chips is a somewhat arbitrary choice. They had to pick *something* as the base for SetPatch to expect, and to load updated modules from that base. 3.1 makes sense as a choice because it was the newest KS released by Commodore. But, you can preempt that process by just softkicking 3.2 at the beginning of your startup-sequence and all should be well.
 
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I considered using skick to skip the requirement, but I haven't found any .rtb and .pat files for roms newer than 3.1
 
ah that brings back memories lol. I haven't used skick in a long long time. Admittedly, I had blizkick in mind which doesn't need the patch files and can just take a KS ROM image.

If you don't have an accelerator that would work with blizkick, maybe you could extract all of the modules from the KS image and use LoadModule to load them all? 🤔
 
As far as I’m aware.

A500+ and previous versions 2.04 had no ide and any boot rom had to sit on the cpu bus like the side car or zorro slot hdd addons. Even some ram didn’t have autoconfig in rom.

Only the a600 kick 2.05 has the ide enabled and that wasn’t all a600 versions
37 .299 didn’t have ide. .
37.300 did but extremely buggy the sought after a600 is 37.350 supporting large drive ( a few hundred mb as a600 stock was 20mb i had one )

Each version introduces compatibility issues the whole reason for skick.

3.0 also had bugs. Look how long an amiga 1200 takes to boot to the insert floppy screen if no hdd fitted. You would think it was faulty if you didn’t just wait.

3.1 is basically a bug fixed 3.0. Much like the 1.2 to 1.3 rom in the early a500 days

So is 3.0 ok to use. Technically yes but why start off from a bugged rom ??

Even if you’re replacing the rom via software patches to 3.2 and higher i would prefer to start off from a less buggy version.

If your burning the legally supplied roms the base all newer versions use is 3.1 for that very reason.

Just my 2cents. If i wasn’t so lazy in learning i would burn my own custom roms adding what modules setpatch would use to rom save the double boot that had to be done to “Patch” older bugged or outdated rom info.
 
Well you say "why start off from a bugged rom", well, I'd be softkicking a non-bugged one right away. The old rom wouldn't be used anymore, its just there to load a new one off disk, so I can just as well say "why waste umpteen quid on some new roms?"

On a different machine (no longer own it) I went from 3.0 roms to 3.1 roms so I could use 3.9, then 3.1.4 came out so I bought 3.1.4 and got some rom chips done, then 3.2 came out, then 3.2.whatever came out that also patches the roms. So for all that I'd spent as much on rom chips as I had spent on the machine itself and i was stil doing the softkick double boot. At that point I said no more wasting money on roms.

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I just did a little experiment with a blank CF card in winuae, installed 3.2 using a 3.1 kickstart. Went fine. However, putting the 3.0 kickstart we get "not a dos disk in DH0:". I can only assume 3.2's made some changes to FFS that KS3.0 can't handle.

Will try again this time setting up the CF card using 3.0's HDToolbox, so that KS3.0 will be able to read the disc.
 
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Booting soft rom is fine for workbench and associated software but not for games or illegally written software that directly accesses the physical rom which no amount of skick or patches will prevent

I used to code in devpac and always used the amiga libraries NEVER calling routines from rom. This gave my “Demo” a near 100% compatibility with any kick revision also taking into account if only 512k chip ram was available.

So an actual 3.1 or whatever would work better than a soft 3.1. Programmers in asm can be lazy and when asking an os what rom “version” command would show the currently loaded rom not the actual physical rom causing all kinds of tom foolery if the coder took shortcuts

This was bad behaviour brought over from the likes of the C64 where they where all technically the exact same. No different roms to mess with unless a 3rd party was loaded like jiffy or simon etc.
 
But if compatibility with disc booting games and demos mattered you'd not want an updated rom anyway. You'd probably want KS1.3 in an A500 and spend all your time in a rocking chair with a shotgun on your lap in case anyone dared to upgrade it.
 
Its also illegally written programs that directly accesses the installed rom. No amount of soft booted roms would avoid that. Even for workbench loaded software

As others have said the latest commodre rom was 3.1 and anything written since assumes a start base of 3.1

Yes will probably work with 3.0 unless programming shortcuts took etc causing complications. That’s why 3.1 is the norm.
 
So what's out there that directly accesses the hardware rom, and is OK with a 3.1 rom and OK with a 3.2 rom but dies on a 3.0 rom?
 
Thats the question. Probably not much but in the past when a system was showing strange behaviours or failings on os 3.9 etc replacing the physical 3.0 for 3.1/3.2 cured some issues but did it also introduce new ones ??

Welcome to Amiga the reason i run stock 3.1
 
They don't actually load the whole KS into memory, just the additional or upgraded modules
kyle_b said:
I considered using skick to skip the requirement, but I haven't found any .rtb and .pat files for roms newer than 3.1
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most people are making their own custom rom set with the modules they need and newer roms are still sold so sites like Amibay it's not allowed to distribute the files (unless selling a licenced copy of course)
 
rtb and pat files don't have kickstart contents or any other copyrighted stuff. They're relocation tables and other metadata for running the kickstart out of ram without an MMU.
 
kyle_b said:
So what's out there that directly accesses the hardware rom, and is OK with a 3.1 rom and OK with a 3.2 rom but dies on a 3.0 rom?
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Remember that 3.0 ROMs were only available on the 1200/4000, and 3.1 is thus the common base that makes sense across the board.
 
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