Why no FPGA accelerator cards?

[Khephren]

Why even bother posting stats like that? Never going to happen.
.

Perhaps I should say, as good as a current accelerator card. I see no reason why that would not be (theoretically) possible, especially with WHDload in the equation.
They also said Amiga emulation would not happen.

[fishy_fiz]

It's hard to imagine why anyone would want to keep using old 3.5 MHz graphics chips when SuperAGA is slated to run quite a bit faster.  The basic idea is that replacing the entire motherboard with an FPGA-based board would be more practical and cost effective than replacing only the CPU.

It will take some time before we get to that stage but things are looking toward the full motherboard replacement avenue and will be the most practical at least for the NatAmi MX board.

One could also argue that it doesnt make sense to use super aga when there's a plethora of faster options available for less money too. Simple fact is ocs/ecs/aga have been around for a long time and there's a lot of software for them that people want to use (as do some rtg standards). I understand the want for super aga, and I find it potentially interesting as well, but ocs/ecs/aga/rtg are more useful for now.

[vidarh]

One could also argue that it doesnt make sense to use super aga when there's a plethora of faster options available for less money too. Simple fact is ocs/ecs/aga have been around for a long time and there's a lot of software for them that people want to use (as do some rtg standards). I understand the want for super aga, and I find it potentially interesting as well, but ocs/ecs/aga/rtg are more useful for now.

SuperAGA is backwards compatible, and writing RTG drivers for it would be feasible too. The point is that it makes no sense to build an expensive FPGA based accelerator and then hook it up to ancient hardware that will ensure it can't possibly give optimal performance, when you can fit the rest of the Natami (or FPGA Arcade/ Replay) cores on the same FPGA for little extra cost and end up with a far faster and more capable system that's still backwards compatible.

You sacrifice 100% compatibility the moment you ditch a cycle exact 68000 anyway.

[Crom00]

How about a low cost ARM cpu board that runs an emulation layer of somekind? I figure the ARM is a good route because the CPU is so wideley used and thereI figure it's all well documented.

As for not possible comments... projects like this are done all the time look at any TV game develoment or throw MP4 players with full 24 bit dispalys in the palm of your hand...

So the Amiga had SOME custom silicon... and thus  that makes it so unique and un-doable...? plz... the biggest drawback seems to be the current IP holder.

Cool that the Amiga Iphone App is coming out. Hope they give full support instead of a game player. I'm sure they will block WB disks from booting.

[bloodline]

How about a low cost ARM cpu board that runs an emulation layer of somekind? I figure the ARM is a good route because the CPU is so wideley used and thereI figure it's all well documented.

Exactly what I would do. I have done a bit of feasibility testing with my ARM M3 Dev board too.

[Digiman]

Well if you can't do an 060 FPGA core for less than an actual 060 chip on an accelerator card then don't. The guy asked a simple question.

As to 3.5mhz chipset<----?? The bus is 7mhz, so is the chipset (well actually the whole thing is run at 28mhz I believe and clocked down to 7.09 or 7.14mhz IIRC)

And an Amiga is an Amiga, never had a problem running any non-AGA game on my A1000 so clearly an actual Amiga with an actual 68000 on the motherboard with a cpu accelerator which can be disabled is far more compatible than anything else. Ditto with an A1200 for AGA games. I don't get the problem, only games need that sort of compatibility.

As to the person putting Minimig into an actual Amiga case.....what you need is an A1200 keyboard and PS/2 keyboard adaptor and just use it inside an A1200 case etc. Problem solved for putting it all inside the machine. I did this myself with a mini-ITX board and said components to build a WinUAE machine inside an old A1200 case....pretty sick having x86 inside the A1200 case I know sorry!

[SamuraiCrow]

Well if you can't do an 060 FPGA core for less than an actual 060 chip on an accelerator card then don't. The guy asked a simple question.

As to 3.5mhz chipset<----?? The bus is 7mhz, so is the chipset (well actually the whole thing is run at 28mhz I believe and clocked down to 7.09 or 7.14mhz IIRC)

That reference was referring to the A500 assuming it has all Chip RAM and no Fast RAM in its defualt configuration.  The A500 did not have 70 nanosecond memory capable of 14 MHz bus access and therefore the CPU and chipset had to split the 7 MHz bus speed between themselves taking every other clock cycle for each.

[yaqube]

The A500 did not have 70 nanosecond memory capable of 14 MHz bus access and therefore the CPU and chipset had to split the 7 MHz bus speed between themselves taking every other clock cycle for each.

I'm sorry but you are talking bollocks. In every Amiga chipset (OCS/ECS/AGA) the Chip RAM memory bus is run at ~3.5 MHz. The CPU can access every other memory cycle at most while the chipset DMA can access all of them (and can block the CPU for long periods).

[SamuraiCrow]

I'm sorry but you are talking bollocks. In every Amiga chipset (OCS/ECS/AGA) the Chip RAM memory bus is run at ~3.5 MHz. The CPU can access every other memory cycle at most while the chipset DMA can access all of them (and can block the CPU for long periods).

Wow!  That's even slower than I realized!

[commodorejohn]

It's not all that slow, IIRC, as the 68000 only accesses memory every other cycle anyway (I could be wrong on that, but I believe that's the case.) And the chipset only steals CPU cycles when the software specifically gives permission (and maybe in 6bpp video modes, but I can't quite recall.) The Amiga hardware reference manual has a lot of good information on chipset/CPU timing.

[psxphill]

when you can fit the rest of the Natami (or FPGA Arcade/ Replay) cores on the same FPGA for little extra cost and end up with a far faster and more capable system that's still backwards compatible.

An fpga on an accelerator card with some ram is going to cost considerably less than a natami. Both in terms of materials and assembly cost.