exxos's Atari, Amiga & retro forum

@agranlund has been busy with System 7.5 and Basilisk II Emulator

So.. this is super early and far from done, but it just managed to boot to desktop and I thought that was exciting enough to share
It's the Basilisk II emulator and I've been off and on toying with porting it to the Atari. Here it is booting an .iso image of the System 7.5 installation CD.

This is very interesting! Thanks for sharing.

The emulation seems to be enough for running MacOS, so my question is: what's missing?

Agv

Very cool. I saw Anders popped up in my YooToob feed but hadn't had a look at that yet!

I do love me an emulator project.

BW

That's pretty damn impressive.

Yeah... might mean that after 30 years I finally get my TT to run as a Mac, seeing as Spectre GCR doesn't work on it.

(I do wonder why Spectre GCR actually runs slower on the ST+TF536 than it does on a stock ST.)

IIRC this was already ported to Atari.

thorsten.otto wrote: ↑Thu Feb 10, 2022 10:14 am IIRC this was already ported to Atari.

I know it had an Amiga port, I wasn't able to find an Atari one.

I know of Aladdin (ST only), Spectre in its various guises (ST and TT) and of MiniVMac (full blown port -- actually emulates 68k instructions! Slower than a wet weekend in the West Country. Not sure if it'd even be usable on a CT60).

BW

Badwolf wrote: ↑Thu Feb 10, 2022 12:07 pm... MiniVMac (full blown port -- actually emulates 68k instructions! Slower than a wet weekend in the West Country. Not sure if it'd even be usable on a CT60).

about x2 than original speed on a FireBee. Pretty usable, I'd say (I don't use it anyway as I don't have any interest in prehistoric Macs).

This has been an off and on thing for a while now. Mostly off to be fair - there's only so much staring at a debugger one can take

Pretty excited that it now actually runs!
There are many things still left to do before I consider it usable by people other than myself but the hardest part is done.

It supports OS7 and OS8. Even though OS8 officially requires a 68040, it does run on '030, with the same caveats that applies if you do it on a real Macintosh..


I have long considered removing the ET4000 in favour of playing with Troed's doubleST idea, but I think I'll keep the gfx card in now:

(sorry about the dusty Atari pictures, it's been tucked away unused and unloved for quite some time)


Going to try and hunt down a few Macintosh II-era games. Warcraft1, the later Sierra games, and so on would be really cool to try out.


Access to video memory is obviously slower than on an equivalent Macintosh due to the slow 8Mhz Atari ST bus. I suppose a Mega STE, TT and Falcon would fare better in that regard.
Mono through the Shifter is obviously a lot quicker but 256 color on the ET4000 is fully usable and feels quick, or at least exactly the same as the ET4000 does in TOS/MiNT.

Disk speed is crazy slow at the moment. The hdd/cdrom disk image code is a bare minimum naive implementation at the moment, just enough to make it work for now.

thorsten.otto wrote: ↑Thu Feb 10, 2022 10:14 am IIRC this was already ported to Atari.

You are probably thinking of Mini vMac which has quite hefty system requirements due to emulating the CPU. (Or a direct port of generic SDL Basilisk II, with CPU emulation)

This runs directly on the CPU so will get near native speed.
Of course, there is some overhead in providing the virtualised environment for Mac (and TOS, since I keep it around and working) but it's nowhere near the penalty of emulating the CPU.

Nice work @agranlund