Where do you draw the line ?

[exxos]

I keep thinking about the H5 and FPGA. it's clear old chips are impossible to find now, even generic stuff.

The H5 direction is of course to replace the BLITTER , GLUE ,MMU with FPGA, similar to the STE GST IC. The shifter gets replaced to give HDMI output.

The next problems are the DMA and 1772. Those would also end up in a FPGA.

The problem is, there isn't much left other than the sound chip, acia, mfp. It wouldn't make much sense to have a FPGA and have those seperate. Some might moan about wanting a real sound chip, but they are still obtainable .

But if all the main ICs are in fpga, haven't we just recreated the MiST but with some likely not so useful legacy ports ?

If old ports were removed then the motherboard could be much smaller and cheaper to produce. But I can't really see there being room in the market for such a system as MiST pretty much got it covered and I don't want to recreate the mist.

Mostly the H4 /H5 platform was to replace broken Atari motherboards and also allow me to develop upgrades without having to spend 95% of the time chasing random faults on original machines. But also they make a easy upgrade option for people and include all the tweaks and fixes. H5 add-ons are still going to be produced but it's taking a lot longer to get things done than I anticipated.

The next series is a FPGA add-on where it's always been my goal and dream, to have a proper 32mhz bus so no need for accelerators at all then. Well unless you want a 030 32bit CPU. But that's one to puzzle over another time.

In terms of development I think the 32mhz GST add-on will likely be where I will end the H5 series. There could be a lot of add-ons worked on. But we are lacking developers these days as a whole.

So I'm thinking it would be a good point to stop development once a 32mhz system is done. It's a bridge between a legacy machine and a faster system where multiple add-ons can be used. I'd like to add some STE stuff eventually like DMA sound etc.

There is also the fact that parts are getting expensive, so it wouldn't be a good idea to produce another motherboard these days. Plus I'm not such a young man anymore and naturally slowing down :)

I don't know if anyone else has any ideas or thoughts on all this ? I mean if all the chips went fpga , we kinda are a very large MiST then. Or we basically reinvent the Suska. Where do we draw the line ?

[dad664npc]

Personally, I don't care what's under the hood! So long as it runs original software.
The one caveat for me is - keep the original casing.

As far as physical I/O goes, I guess people have invested a lot of money over the years in various upgrades, so I think any solution will need to include the most common interfaces.

I will add, for me to be interested in a modern version, it would ideally have a Falcon mode (68030+FPU+SVGA) - hmmm what about incorporating a PiStorm - it does all of that :o self promotion :lol:

[PhilC]

My wish list would have one more board with an fpga on it and then ditch the sockets for the chips that we can no longer easily source but keep the 68K and all the 68K sockets and ports, so that it looks like and functions like an H5 but is a combination of both old and new.

[exxos]

My wish list would have one more board with an fpga on it and then ditch the sockets for the chips that we can no longer easily source but keep the 68K and all the 68K sockets and ports, so that it looks like and functions like an H5 but is a combination of both old and new.

That would be what a future board would likely be. But also could be made much smaller. Though as the boards struggle to sell I doubt producing any new boards is going to be viable.

[PhilC]

My wish list would have one more board with an fpga on it and then ditch the sockets for the chips that we can no longer easily source but keep the 68K and all the 68K sockets and ports, so that it looks like and functions like an H5 but is a combination of both old and new.

That would be what a future board would likely be. But also could be made much smaller. Though as the boards struggle to sell I doubt producing any new boards is going to be viable.

It may be you do the same as for the Alpha? just a select few have them and you don't need to get all the sockets etc fitted as we would be more than capable of doing that as you know.

[sporniket]

I believe that you have a not so fuzzy picture in mind of what you want to achieve : a 32Mhz bus, and not being a repeat of the Mist/Mister/whatever all in one FPGA thingy.

About colocating some chips in the same FPGA, I believe that going the way of the "COMBEL" (glue + mmu + other optionnal things if appropriate, like the blitter) would be a good balance, provided that you have enough GPIOs (that's the other critical point to me) .

About the final shape and feature set, I believe that what matters is what you want to achieve, because at the end of the day it is your vision. Like a luthier making classical guitars.

[chronicthehedgehog]

I guess if you ever intended to support the 64bit Apollo 68080 core (or perhaps some other hacked core with LL op sizes), the redesigned ancillary chips would need to be FPGA anyway

If the ST line was still going, Atari (or whoever) would have long ago moved towards using more custom chips. They'd have followed the trend and had a 'bigger' bus for more cards - graphics/sound etc. Like you're doing with the H5 anyway

It's a bit like how BMW redesigned the mini - imagining how it would have incrementally progressed.

[stephen_usher]

I agree, if you are looking at an "evolution" of the ST platform then imagine how Atari may have gone forward.

Moving all the glue logic into one chip, simulating the ST's video but adding more flexibility, as per the Falcon, would have been their first step.

Looking later into the 90s they would probably have seen what's coming and offered an expansion bus, probably PCI, as many other non-Intel platforms started to do, and put graphics onto that rather than having them memory mapped, maybe with a co-processor talking to the graphics card to maintain backward games compatibility. They would have moved to a 32 bit data bus too.

I think what I'm saying is the line to be drawn is really where everything is simulated in one chip as a software defined architecture.

[exxos]

It may be you do the same as for the Alpha? just a select few have them and you don't need to get all the sockets etc fitted as we would be more than capable of doing that as you know.

Possibly yes. A lot of stuff got more complicated like the audio circuit. I think it would be a bit of a PITA to solder all the SMT stuff now. But I definitely think the birdseed board which is smaller could definitely be done.

I would probably rehash something like the legacy board layout wise. I mean squashing everything up on the board is already half the size.

The main problem with the legacy board is that the simm socket takes up a lot of room. Without it the cartridge port could basically go on a extender board. Then we are really getting into a different case. The legacy board will actually fit in a original case as is without having to do anything else. RAM would likely go on the FPGA board anyway. There might be room for more 68K ports then anyway.

[exxos]

I believe that you have a not so fuzzy picture in mind of what you want to achieve : a 32Mhz bus, and not being a repeat of the Mist/Mister/whatever all in one FPGA thingy.

About colocating some chips in the same FPGA, I believe that going the way of the "COMBEL" (glue + mmu + other optionnal things if appropriate, like the blitter) would be a good balance, provided that you have enough GPIOs (that's the other critical point to me) .

About the final shape and feature set, I believe that what matters is what you want to achieve, because at the end of the day it is your vision. Like a luthier making classical guitars.

I do have a vision where I want to take the project yes. But a lot of stuff planned I'm not going to have the time or ever get around to doing. I think there is only so far a legacy board can realistically be taken now.

It is a little odd that the shifter wasn't inbuilt in the GST. Possibly was just easier or quicker or cheaper to do it separately. But I do believe the shifter would have gone integrated as well as a next step by Atari.

The legacy board was a direction towards making a lower cost motherboard. Though I don't think it will get done because there is still the same problem of sources for original chips.

In order to attract new people to the Atari scene, and needs to be some sort of low-cost board and going FPGA is the only way. If we can get machine with also a 32MHz bus. I think it would be a good machine.