8 ms·

From a hobbyist and preservation perspective, it would be cool if this could be used to produce some form of the Apollo 68080 core to revive the 68k architectur

by DCKing 6y ago

From a hobbyist and preservation perspective, it would be cool if this could be used to produce some form of the Apollo 68080 core to revive the 68k architecture a little bit, and build out the Debian m68k port [0][1]. The last "big" 68k chips were produced in 1995 (that would be a 350nm process?) so this could be hugely improved on 130nm. The 68080 core is currently implemented in FPGAs only and is already the fastest 68k hardware out there. With a real chip, people could continue upgrading their Amigas and Ataris. [0]: http://www.apollo-core.com/ http://www.apollo-core.com/ I can't easily find how "open source" it is though, but it's free to download. [1]: https://news.ycombinator.com/item?id=23668057 https://news.ycombinator.com/item?id=23668057

herio 6y ago
The Apollo core is not open source. There are some other pretty nice and featured 68k cores that are open source (TG68, WF68K30L etc.) but none that is really close to the features and performance of the Apollo 68080.
- DCKing 6y ago
  Ah that's a shame. I suppose this could be used to perform a revival of 68k without the Apollo core, but it's a shame that the engineering effort already there would not be available. Maybe this would be an incentive for them to open source it, but yeah.
  - phonon 6y ago
    They have a slack channel... :-) https://wiki.apollo-accelerators.com/doku.php/about_us:links https://wiki.apollo-accelerators.com/doku.php/about_us:links
- armitron 6y ago
  Note that there have been IP theft and other shadiness allegations from ex-members of the Apollo team. If you do a little research you'll find out that there's plenty of "stay away" and "can't believe they haven't been sued into oblivion yet" indicators and all sorts of misleading claims and marketing. My summary would be that it's a tightly-controlled, closed project lead by questionable people with well-documented histories of questionable practices including ignoring copyrights, distributing infringing software, deleting critical posts from their forums and putting out misleading information.
  - DCKing 6y ago
    It seems I have a little bit more to learn on this project. Are there any sources I could read?
rwmj 6y ago
How fast can those FPGAs be clocked? Is it better to have a free but small run of 68k ASICs which might have similar performance, or the potential to run a soft core on off-the-shelf FPGAs, at much higher cost per unit, but with the ability to rapidly iterate on the design?
- DCKing 6y ago
  The Apollo project here would be particularly suitable as they have already iterated on the design using FPGAs. The chip is already working as an FPGA and bringing tangible improvements: I'm assuming a 130nm ASIC version would be even better.
  - rwmj 6y ago
    I'm not sure that assumption is necessarily right. As a general guide, on a cheap (sub $200) modern FPGA I can clock an RV64 core at 50-100 MHz. As you spend more on the FPGA, you can get higher clock rates and/or more cores. Also it should be possible to clock 32 bit cores higher (perhaps much higher) because there will be fewer data paths for internal routing to skew. On the other hand, modern RISC architectures are designed for this, whereas old 68k architectures may not be.
    - cmrdporcupine 6y ago
      I had no problem running PicoRV32 at 50mhz (maybe higher... 75mhz? can't recall, at that point I had other issues that might not have been CPU related) on an Artix 7 35t. Honestly instead of chasing after new 68k silicon it'd be better to just emulate on a modern processor. Not the same romance, I know....but
- pclmulqdq 6y ago
  The soft core approach has many advantages, but FPGA companies have dropped the ball on single-unit (hobbyist) sales. Chips that cost $1000 from a distributor cost 1/10th to 1/100th the price when you have a relationship with the manufacturer, mostly because distributors can't sell them very quickly and have to keep a ton of stock to have the SKUs you want. On a modern FPGA, processor clocks of 200-300 MHz are possible to get with designs that aren't huge.
pjc50 6y ago
What happened to freescale/NXP "Coldfire"?
- herio 6y ago
  ColdFire is still around but is also not fully binary compatible with 68k. There have been attempts at making Amiga accelerator cards using Coldfires, but I don't think I've ever seen one that was fully finished.
  - cmrdporcupine 6y ago
    It's not fully binary compatible but pretty damn close. People working on the Firebee were able to make it run pretty smooth, there's some things you can do to trap the old instructions and rewrite. It's never going to work for games and the like, but games and the like from that era have all sorts of other video hardware specific dependencies that are even more difficult to satisfy. It really is "spiritually" a 68k series processor, just with some cleaning up. I like it.
- DCKing 6y ago
  I am really not an expert in 68k but the Coldfire does not appear to be fully compatible with the old 68ks used in old Macs and Amigas, and Googling around it doesn't appear to have had much uptake if any. It's not being made anymore either.
  - CompAidedPoster 6y ago
    Coldfires are definitely still in production.
- pantalaimon 6y ago
  I guess everyone is just using ARM now.
- cmrdporcupine 6y ago
  No new Coldfire processors made in years, unfortunately. Freescale/NXP seems to be just leaving it.
phire 6y ago
You would have problems with licensing the 68k ISA. I believe freescale currently owns the architecture, and still manufactures some 68k microcontroller cores.
- DCKing 6y ago
  Interesting thing to consider. I wonder how actively people want to protect 68k, as not even Freescale/NXP seems to use it anymore. Shouldn't that already be problematic for the 68k projects in hardware through FPGAs? Apollo already does it and sells hardware, and the MiSTER project also does it by releasing FPGA designs for e.g. the Sega Genesis which has a 68k processor. Is it a different story if you embed 68k in an ASIC?
  - afwaller 6y ago
    Texas Instruments still sells graphing calculators with 68k processors (TI-89 series, most commonly)
- nullc 6y ago
  > I believe freescale currently owns the architecture, Owns it how? 68060-- the last of 68k's designs-- was released in 1994. Any patents should now be expired.
  - webmaven 6y ago
    > > I believe freescale currently owns the architecture, > Owns it how? 68060-- the last of 68k's designs-- was released in 1994. Any patents should now be expired. Sure, patents wouldn't be a barrier to clone the design and create an equivalent using the same patented ideas, but copyright still prevents you from copying the design, and will prevent copying significant parts of the design as well.
    - colejohnson66 6y ago
      In other words: you can rearchitect it from scratch, but you probably can’t extract the die.
CompAidedPoster 6y ago
68060 - 600 nm
moftz 6y ago
The PowerPC 7457 was built on a 130nm process, used in the AmigaOne XE as well as the Apple G4 machines. That's probably about as good as you will get for an community-led chip fabrication. You could probably get it up to over 1GHz if you made a 68k at this size. A modern FPGA is probably the better way to go for this kind of thing. I doubt this free fab includes things like die testing and packaging. That's an expensive process so someone would need to front some money to actually get the testing and packaging done for enough chips to make the cost actually worth it. It would be much cheaper to design an interposer board that could plug into a motherboard to take the place of the original 68k. This would also allow you to continuously upgrade the processor without requiring a whole new fab to take place.
- perl4ever 6y ago
  >You could probably get it up to over 1GHz if you made a 68k at this size That would be a fun upgrade if I had an old 68k Mac in good condition. I've thought occasionally about what if Motorola had had the resources to continue developing 68k like x86.
  - cmrdporcupine 6y ago
    Coldfire is what they would have, and did, make. By dropping a few problematic instructions they were able to use a more RISC-like approach and produce a nicer core. Most code just needs a recompile, or you can trap the old instructions and work around them. I have a "Firebee", an Atari ST-like machine built around a 264mhz coldfire, and it's quite nice. My understanding is that Coldfire got used in a lot of networking hardware, due in part to its network order endianness, and partially because Freescale put network hardware support into some of the cores. But there is no continuing demand for Coldfire, really, so it has stalled, NXP never continued on with it and is going the ARM route now, like everyone else.

by DCKing 6y ago

herio 6y ago

The Apollo core is not open source. There are some other pretty nice and featured 68k cores that are open source (TG68, WF68K30L etc.) but none that is really close to the features and performance of the Apollo 68080.

DCKing 6y ago
Ah that's a shame. I suppose this could be used to perform a revival of 68k without the Apollo core, but it's a shame that the engineering effort already there would not be available. Maybe this would be an incentive for them to open source it, but yeah.
- phonon 6y ago
  They have a slack channel... :-) https://wiki.apollo-accelerators.com/doku.php/about_us:links https://wiki.apollo-accelerators.com/doku.php/about_us:links
armitron 6y ago
Note that there have been IP theft and other shadiness allegations from ex-members of the Apollo team. If you do a little research you'll find out that there's plenty of "stay away" and "can't believe they haven't been sued into oblivion yet" indicators and all sorts of misleading claims and marketing. My summary would be that it's a tightly-controlled, closed project lead by questionable people with well-documented histories of questionable practices including ignoring copyrights, distributing infringing software, deleting critical posts from their forums and putting out misleading information.
- DCKing 6y ago
  It seems I have a little bit more to learn on this project. Are there any sources I could read?

rwmj 6y ago

How fast can those FPGAs be clocked? Is it better to have a free but small run of 68k ASICs which might have similar performance, or the potential to run a soft core on off-the-shelf FPGAs, at much higher cost per unit, but with the ability to rapidly iterate on the design?

DCKing 6y ago
The Apollo project here would be particularly suitable as they have already iterated on the design using FPGAs. The chip is already working as an FPGA and bringing tangible improvements: I'm assuming a 130nm ASIC version would be even better.
- rwmj 6y ago
  I'm not sure that assumption is necessarily right. As a general guide, on a cheap (sub $200) modern FPGA I can clock an RV64 core at 50-100 MHz. As you spend more on the FPGA, you can get higher clock rates and/or more cores. Also it should be possible to clock 32 bit cores higher (perhaps much higher) because there will be fewer data paths for internal routing to skew. On the other hand, modern RISC architectures are designed for this, whereas old 68k architectures may not be.
  - cmrdporcupine 6y ago
    I had no problem running PicoRV32 at 50mhz (maybe higher... 75mhz? can't recall, at that point I had other issues that might not have been CPU related) on an Artix 7 35t. Honestly instead of chasing after new 68k silicon it'd be better to just emulate on a modern processor. Not the same romance, I know....but
pclmulqdq 6y ago
The soft core approach has many advantages, but FPGA companies have dropped the ball on single-unit (hobbyist) sales. Chips that cost $1000 from a distributor cost 1/10th to 1/100th the price when you have a relationship with the manufacturer, mostly because distributors can't sell them very quickly and have to keep a ton of stock to have the SKUs you want. On a modern FPGA, processor clocks of 200-300 MHz are possible to get with designs that aren't huge.

pjc50 6y ago

What happened to freescale/NXP "Coldfire"?

herio 6y ago
ColdFire is still around but is also not fully binary compatible with 68k. There have been attempts at making Amiga accelerator cards using Coldfires, but I don't think I've ever seen one that was fully finished.
- cmrdporcupine 6y ago
  It's not fully binary compatible but pretty damn close. People working on the Firebee were able to make it run pretty smooth, there's some things you can do to trap the old instructions and rewrite. It's never going to work for games and the like, but games and the like from that era have all sorts of other video hardware specific dependencies that are even more difficult to satisfy. It really is "spiritually" a 68k series processor, just with some cleaning up. I like it.
DCKing 6y ago
I am really not an expert in 68k but the Coldfire does not appear to be fully compatible with the old 68ks used in old Macs and Amigas, and Googling around it doesn't appear to have had much uptake if any. It's not being made anymore either.
- CompAidedPoster 6y ago
  Coldfires are definitely still in production.
pantalaimon 6y ago
I guess everyone is just using ARM now.
cmrdporcupine 6y ago
No new Coldfire processors made in years, unfortunately. Freescale/NXP seems to be just leaving it.

phire 6y ago

You would have problems with licensing the 68k ISA. I believe freescale currently owns the architecture, and still manufactures some 68k microcontroller cores.

DCKing 6y ago
Interesting thing to consider. I wonder how actively people want to protect 68k, as not even Freescale/NXP seems to use it anymore. Shouldn't that already be problematic for the 68k projects in hardware through FPGAs? Apollo already does it and sells hardware, and the MiSTER project also does it by releasing FPGA designs for e.g. the Sega Genesis which has a 68k processor. Is it a different story if you embed 68k in an ASIC?
- afwaller 6y ago
  Texas Instruments still sells graphing calculators with 68k processors (TI-89 series, most commonly)
nullc 6y ago
> I believe freescale currently owns the architecture, Owns it how? 68060-- the last of 68k's designs-- was released in 1994. Any patents should now be expired.
- webmaven 6y ago
  > > I believe freescale currently owns the architecture, > Owns it how? 68060-- the last of 68k's designs-- was released in 1994. Any patents should now be expired. Sure, patents wouldn't be a barrier to clone the design and create an equivalent using the same patented ideas, but copyright still prevents you from copying the design, and will prevent copying significant parts of the design as well.
  - colejohnson66 6y ago
    In other words: you can rearchitect it from scratch, but you probably can’t extract the die.

CompAidedPoster 6y ago

68060 - 600 nm

moftz 6y ago

The PowerPC 7457 was built on a 130nm process, used in the AmigaOne XE as well as the Apple G4 machines. That's probably about as good as you will get for an community-led chip fabrication. You could probably get it up to over 1GHz if you made a 68k at this size. A modern FPGA is probably the better way to go for this kind of thing. I doubt this free fab includes things like die testing and packaging. That's an expensive process so someone would need to front some money to actually get the testing and packaging done for enough chips to make the cost actually worth it. It would be much cheaper to design an interposer board that could plug into a motherboard to take the place of the original 68k. This would also allow you to continuously upgrade the processor without requiring a whole new fab to take place.

perl4ever 6y ago
>You could probably get it up to over 1GHz if you made a 68k at this size That would be a fun upgrade if I had an old 68k Mac in good condition. I've thought occasionally about what if Motorola had had the resources to continue developing 68k like x86.
- cmrdporcupine 6y ago
  Coldfire is what they would have, and did, make. By dropping a few problematic instructions they were able to use a more RISC-like approach and produce a nicer core. Most code just needs a recompile, or you can trap the old instructions and work around them. I have a "Firebee", an Atari ST-like machine built around a 264mhz coldfire, and it's quite nice. My understanding is that Coldfire got used in a lot of networking hardware, due in part to its network order endianness, and partially because Freescale put network hardware support into some of the cores. But there is no continuing demand for Coldfire, really, so it has stalled, NXP never continued on with it and is going the ARM route now, like everyone else.