OS 3.5/3.9 WITH KS 3.0?

[Piru]

As I understood it, OS3.9 patches the kickstart anyway, so without a proper 3.1 kickstart (ie. chip based, not softkicked) it wont work anyway.

The Kickstart 3.1 requirement in AmigaOS 3.5/3.9 is artificial. The image itself is not patched (that is impossible, it is ROM after all), but KickMem and KickTag pointers are used to replace complete resident modules (libraries/devices/resources and such), as documented already in the original RKRMs.

AmigaOS 3.9 BoingBag2 introduced exec.library replacement, so there is no excuse of requiring 3.1 ROM, all modules can be replaced anyway. Earlier the argument was that not all modules could be replaced, for example exec.library and expansion.library.

Thus in theory Kickstart 2.0x would have been sufficient for AmigaOS 3.5/3.9. The SetPatch "AmigaOS ROM Update" loader would have replaced more modules for older kickstarts: KS 2.0x and 3.0 would have been patched upto 3.1 + the OS 3.5/3.9 modules.

One can only speculate the real reason for requiring Kickstart 3.1. The coder's lazyness, H&P's desire to sell more 3.1 ROM chips bundled with AmigaOS 3.5/3.9, or something else... I guess there is no way to know now.

[Piru]

...or the fact that it was only sold as an UPGRADE

Really? Interesting...

What for the AmigaOS 3.5 package had tickbox for "Kickstart 3.1 chip included" then?

--edit--
chip not image

[Piru]

Workbench 3.1 and 3.5 are on the CD (just checked). You had to pay extra to get the Kickstart 3.1 chip also. There is a tickbox on the side of the AmigaOS 3.5 package to indicate if one is included.

I have no clue if the original package was to include it, or if the dealer was supposed to package one inside it and tick the tickbox.

AmigaOS 3.5 could have easily been made not to require Kickstart 3.1 chip.

Lots of ppl paid for 3.1 chip for nothing, in my opinion.

[Piru]

an aweful lot of people already had 3.1(besides CD32 and A 4000 T owners i mean)

All but AT and later A1200s had Kickstart 3.0.

firstly it would of ment more patches
it would also mean that there are two different previous versions to upgrade from floating around, the software would probably need to be written to patch different things depending on the ROM, which would make the software larger, probably slower, and more difficult to debug/maintain for the developers

I explained this once already.

There would have been modules for Kickstart 2.x and 3.0 to upgrade these to Kickstart 3.1 level. Just simple KickMem/KickTag stuff like always. No separate sw patching or hacking is required. No maintaining is required, as Kickstart 3.1 is fixed in stone. These parts would have been "static", always the same.

Then the 3.5/3.9 modules on top of that. These are the modules where the real work is done.

Then if you would have wanted to save memory and have cleaner system you could have bought true Kickstart 3.1 chip. Here, no patching to Kickstart 3.1 level would have been required, only the 3.5/3.9 modules like now.

I hope I explained this clearly enough now.