Outcast (castaway Module) - Second Alpha Released


What is Cyclone? You mean the "C"-esq programing language?
They are talking about code that emulates cyclone CPU core in Assembly (a very low-level programming langauge). The core was written by fdave I think, but it has since been improved by numerous other programers in the GP32/2X scene.
It would increase the speed of the emu, at the expense of compatability.

The speed of 68000 emulation?

Not that I'm against any optimisation but the 68000@8MHz (as in ST) is at around 1-2mips...

Is it really needed? The rest of machine (the shifter, the Yamaha PSG, the peripherals) is probably consuming most of processor time in such emulator like Castaway. Sacrificing combatibility (if that is so) isn't too good compromise here.
 
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pure fun

scar.jpg
 
Well, as far as I'm aware, the current CPU core that Castaway uses is the same one that Genesis emus used before Cyclone came along (Musashi? Something like that). And Cyclone is a LOT faster than that one, if that is the one being used.

In Genesis emulation, it made the difference between fs4-6 emulation and if you were lucky, a playable speed, and the fs0-1 emulation we see in fGen today. Very very cool core - but iirc it used to cut some corners which made it hard to use in CaSTaway.

Still, if it *does* work in its current version, it'd be cool to see. Obvious advantages would be being able to run the emu at lower speed, and, of course, the possibility of backporting to the GP32, where it would make a very real difference in speed :)
 
I actually don't use the Musashi core.. this one is much faster than Musashi I think, though I've not tested it in years up against it.

Backporting to the gp32 would be nice though..

I'll try it as an option though, so you can pick-a-core :)


003 in a few mins..

jeff
 
Well, as far as I'm aware, the current CPU core that Castaway uses is the same one that Genesis emus used before Cyclone came along (Musashi? Something like that). And Cyclone is a LOT faster than that one, if that is the one being used.

I don't know how Castaway is profiling. If current cpu's code is taking relatively large amount of resources then better 68000 code will improve perfomance obviously. But it'd be unusual, at least it was with all others ST emulators I had been using (the Steem and Pacifist).

Perhaps Castaway is much more officient at emulating ST's internals?
(so doing the 68K needs relatively bigger percent of time)

In Genesis emulation, it made the difference between fs4-6 emulation and if you were lucky, a playable speed, and the fs0-1 emulation we see in fGen today. Very very cool core - but iirc it used to cut some corners which made it hard to use in CaSTaway.

Still, if it *does* work in its current version, it'd be cool to see. Obvious advantages would be being able to run the emu at lower speed, and, of course, the possibility of backporting to the GP32, where it would make a very real difference in speed :)

And it could allow to spend more cycles for more accurate rasters rendering, sound and such.
 
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I actually don't use the Musashi core.. this one is much faster than Musashi I think, though I've not tested it in years up against it.

Backporting to the gp32 would be nice though..

I'll try it as an option though, so you can pick-a-core :)


003 in a few mins..

jeff


The mushashi core is very accurate, and also verrrryyy slllllloooooooooooooowwwwww. *reads slowly in a very deep voice* It was used to test DrMD for cyclone bugs once. It is not real suitable for something on the GP2X that we would like to run in real time.
 
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