Topic: Experimental compute module

Over the weekend at Datastorm I was thinking a lot about which direction to go in next.
The 68060 daughter board is the highest priority at the moment, but as those chips are fairly hard to get, is there another solution?

Personally, I don't believe it makes sense to make a fast CPU in an FPGA. 68020 cycle accurate + some acceleration always for the baseboard, and that CPU will continue to improve. If I was to crank up the FPGA core in an expensive FPGA, it will bear no timing or functional relationship to any existing CPU.

However, we have a nice ARM architecture which costs next to nothing and has a parallel memory interface, 1GB RAM and HDMI out.

The thinking here is to run JUST 680x0 CPU emulation in the PI CM3 and the rest of the system in the FPGA - falling back on the FPGA CPU for cycle accurate stuff.

/Mike

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Re: Experimental compute module

err wait.. so using a raspberry pi for a software emulated CPU?

(dunno why but I thought interfacing something like was not possible)

Re: Experimental compute module

It wasnt, with the cm3 it probably is.

Re: Experimental compute module

Shall I make a little adapter which plugs the cm3 into an A1200?

Re: Experimental compute module

out of curiosity why it would be possible with a pi3?

Adapter for the expansion port?

Re: Experimental compute module

While possibly awesome in practice, you'll probably get a lot of resistance from purists. Some will struggle to see the benefit over UAE.

Re: Experimental compute module

@cunnpole yup probably but hey... that's up to the user in the end smile If that's something possible and "trivial" to have... honestly that would be amazing.

Re: Experimental compute module

I think it's the best of both worlds. The cycle accurate Amiga hardware / video / io is still running on the FPGA. So, it's like a real A1200, with an accelerator card. The Vampire boys make an FPGA CPU which is as close to a real 68060 as the CM3 module is.

As far as I can tell, a lot of UAE emulation is spent on the video. With the CM3 Just being a computer it should be quite fast.
/M

Re: Experimental compute module

It's the compute module which makes it possible - additional IO from the SOC.

Re: Experimental compute module

Software side we could use the CPU used by uae? (You can achieve incredible speed already with FS-UAE on a PI, and doh now I get the CM3 ...).

That sounds really exciting Mike... and if you think it's possible to connect it on athe 1200 expansion port... well smile

Re: Experimental compute module

So if I get this right, we would have a daughter board with a compute module port to plug the CM3? Price wise that sounds really interesting as well.

Re: Experimental compute module

interesting eh? I'm looking at the 68K JIT -> ARM code out there which is widely used.  Should go like the clappers.

Re: Experimental compute module

Yes exactly - which is exactly why I've plugged the CM3 IO board into the expansion board.
If I get basic read/write from the CPU, I'll crank out a daughterboard for people to play with.

It's also interesting to move the "RTG" there as well - the BCM has nice hi-res HDMI out, which doesn't need any hardware emulation. FPGA drives PAL/NTSC/Scandoubled output etc as before.

Re: Experimental compute module

That's super interesting :-D I'm one click buying a dev kit... big_smile

Let's enable the dreaming mode... the bcm got a nice little GPU as well... If we use the cm3 for RTG as well, maybe we could have a Warp3d driver...

Re: Experimental compute module

Personally I'm in the throw-big-FPGA-at-problem camp to have a 68060 compatible (doesn't have to be bus compatible) in the FPGA at the expansion board.
If it doesn't go fast enough then wait for the next generation FPGA and respin the board then.
Have a bunch of stupid fast memory. SRAM?

(Insert picture of Shut Up And Take My Money here while waiting for a board at Amedia...)

Re: Experimental compute module

I sent some boards to Amedia - are you going to get one of those?

CM3 module + 1G ram + HDMI etc ~30USD

big FPGA doing 68K? Expensive / not as fast as ^

Re: Experimental compute module

Just posted on the Amiga FB group. Let's see what the feeling is.
I'll get on with the 68060 board now.

Re: Experimental compute module

and I guess dev time needs to be taken into account to get something fast/compatible etc.. for the FPGA version of the CPU while your idea is to use one of the existing software implementation.

Re: Experimental compute module

MikeJ wrote:

I sent some boards to Amedia - are you going to get one of those?

I would if I could. There is no way to make an order for one. They know I'm interested so I am perhaps on some waiting list.

Re: Experimental compute module

I missed the A1200 adapter part. You mean upgrade my a1200 with a monster of a cpu? If that is doable then that would turn the market upside down again.

I'd certainly take one for the replay and the a1200

21 (edited by JimDrew 2017-02-16 05:37:01)

Re: Experimental compute module

This makes for an amazing FS-UAE emulation setup:

https://www.pine64.org/?page_id=1459

CPU/GPU, 2 gigs of RAM, HDMI, USB, SD card, Ethernet, etc. etc.  Pi-2 interface compatible so you can plug all of your Rpi stuff into it.

I have had this for about 6 months, works great! $29.00!

Re: Experimental compute module

MikeJ wrote:

big FPGA doing 68K? Expensive / not as fast as ^

With MMU?

Re: Experimental compute module

we'll see, not sure.

Progress today. Cross compiler and environment set up. I can build and run stuff now, and play with the device tree.
Currently playing around bashing the SMI peripheral directly as root. I can wiggle a pin so far!

/Mike

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Re: Experimental compute module

I love the wire mess big_smile

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Re: Experimental compute module

mess? looks very tidy for a workplace to me :=)