A sneak peek at the ACA1240/1260 cooling system

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Don't Panic. Please wash hands.
  • Hello Jens, thank you for the reply!


    Regarding my question of concerning allowing customers to potentially supply their own CPUs, I was referring to being able to purchase an ACA1260 or ACA1240 board with an empty socket, fully licensed for whichever CPU they plan to use. I certainly understand the massive collection of counterfeits out there but I'm sure I'm not the only enthusiast who has a surplus of verified legitimate and functional CPUs (unless they've figured out how to counterfeit the IDs in microcode too).


    I guess what I'm saying is, if there was a channel in place to procure an ACA1260 that comes with out the CPU populated for a discount, that's an option I'd personally entertain... even if its sold with the understanding these are to only be used by experienced customers with no implied warranty whatsoever. If I'm a careless/ignorant customer who plugs in a CPU that turns out to be a rebadged 486 and smoke starts bellowing out of a CPLD...that's on me. Perhaps you've had too many negative dealings with unreasonable customers for this to be an option.


    Regardless, nice job on the new accelerator it really does look great!


    Cheers Jens,

    Dieter

  • I was referring to being able to purchase an ACA1260 or ACA1240 board with an empty socket

    Unfortunately, this is not an option unless you have a business and we can make a B2B contract. For B2C business (you are an end-customer), there are fairly strict rules in place. I should only sell fully-working and tested products, otherwise I'd be responsible for "anything you stuff into the socket", and like Iwrote earlier in this thread, there are LOTS of fake CPUs out there.


    The best way that I can protect my business from being made responsible for things that I can't influence is to sell a fully-working card. Essentially, I can "almost" make the offer you're asking for, just with a 68040-25 CPU pre-installed. With the rather low cost of this CPU, you wouldn't save much money by skipping on that anyway: The discount you're looking at would be under 20,- EUR. The huge benefit for me is that I can prove that I have shipped something perfectly working, and you'll be responsible for any modification that you do to the card.


    I'm sure I'm not the only enthusiast who has a surplus of verified legitimate and functional CPUs

    I certainly trust that there are people who have working 060s waiting to be put to good use, but I also need to protect my business. Another suggestion was to have people send their CPUs here, so we can install them. This is also not a good idea, as we may become the bearer of bad news if the CPU turns out to be fake. Even worse: If someone can't accept that he made a loss, he/she may accuse us to have it exchanged for a fake. How would be protect us against that, other than only shipping cards with known-good CPUs?


    Perhaps you've had too many negative dealings with unreasonable customers for this to be an option.

    Unfortunately, that's the reason, yes. The worst thing is that these "unreasonable" customers like to approach us with a lawyer and cause even more cost. I therefore check pretty much everything with a lawyer if it somehow smells like "may conflict with EU directives" or "opens a loophole for criminal activity". I did have quite some expensive learning experience, and I'm pretty happy that the 25MHz-68040 solution is almost what you and others are asking for.

  • Hello Jens,


    I am looking forward to the 040 and 060 and I think your work is amazing. That being said, I have a, maybe, stupid question for you. Why is there an Intel cyclone chip on the picture of the card? Is it only for the prototype? I thought the point of you card versus, for example the vampire accelleration cards, is that there is no FPGA emulation being used.

  • Why is there an Intel cyclone chip on the picture of the card? Is it only for the prototype? I thought the point of you card versus, for example the vampire accelleration cards, is that there is no FPGA emulation being used.

    The fact that we use a real CPU doesn't mean there isn't other logic functions that need to be performed. The main purpose of the FPGA is being the memory controller for the zorro III compatible ram on board. It will also contain a lot of logic for example to talk "Amiga" as that talks 020 bus, which isn't directly compatible with 040/060 bus. In the past this logic would have typically been implemented with CPLDs or PALs/GALs and maybe a Motorola glue chip like the MC68150 (which is nowadays nowhere to be found). Compared with that method, FPGAs have the advantage that it is RAM based, so allow for firmware updates to provide fixes and improvements "in the field". And they have much more logic allowing more features to be packed on a small board. We also use the PLLs in the FPGA to generate the various clocks, like PCLK and BCLK for the 040 CPU.

  • That's an amazing use of the FPGA.

    Thanks - however, I believe it's the originally-intended use of FPGAs. This technology came up in the late 1980s/early 1990s, but I always considered them overpriced and too difficult to handle. I did not see their advantage over CPLDs, as they compared to them pretty directly.


    WIth the chips being RAM-based, they grew at Moore's law, while CPLDs are almost stuck with what they provided in the mid-90s. So I am now replacing CPLDs with FPGAs, which is (in my opinion) their originally-intended use.


    The available amount of logic inside the Cyclone-10 that we use on this board is not enough to host a full 68040/060-variant. However, it's enough to host a very elaborate memory controller that takes full advantage of the SD-Ram on the board: By keeping multiple rows open and hiding refresh cycles (=running these concurrent with memory accesses), we can reach a very high saturation rate on the 68040/060 bus.


    We have a few more tricks up our sleeves that we'll publish as we verify the current prototype, which is already running. Our next step is to verify the chip ram access speed acceleration method that I talked about in another thread on this forum. The complexity of this would probably take an extra CPLD on a conventional accelerator (or at least lots of additional circuitry), but with lots of available logic in the FPGA, it's easily added (provided the external wiring allows for it, which was not the case on the previous prototype).

  • Hallo Jens


    I was wondering what would be the power supply requirements for upcoming ACA1240/60 cards?

    Currently I use original C= PSU that delivers 2.5A on 5V line. It runs smoothly with my ACA1233n/26, but... is it enough for 040 I was planning to buy?

  • I was wondering what would be the power supply requirements for upcoming ACA1240/60 cards?

    That'll be surprisingly low. The ACA1240/1260 uses highly-efficient DC-DC converters to generate the local 3.3V and CPU-core voltages out of the 12V rail of the PSU. With the 12V rail being rated 500mA for the "small" PSUs, there's 6W of power available that hardly influences the delicate 5V rail. I decided to tap that one to gain best stability.


    The good part is that the 12V rail is hardly loaded on today's Amigas, as external floppy drives, 3.5" HDs or even CD-drives are pretty much out of fashion. Everyone likes to go for flash media and a silent system, so the 12V rail is almost "fully available".

  • Any pre-ordering possibilities planned?

    We'll open pre-orders when all parts of the design are verified. However, we have to keep in mind that the Corona virus situation in China is still keeping around 90% of the companies from doing productive work. You do get eMail answers, but those are 99% "please wait until..."-answers from home offices.


    Although we have almost all components in stock already and assembly of them will happen in Germany, the circuit boards come from China. Produktion in Europe is not an option, as the already-expensive companies like to jack up their prices even more now. Further, I'd have to go through the whole quality checks for a new PCB supplier again, and that's really tedious. I'm happy to have two different PCB suppliers in China that allowed me to specify the current and time in the galvanic baths. Try to find that in Europe...

  • Hi, I am very interested in that cards.. 040 for sure, but I was wondering about 060..


    will 060 be stable on AOS 3.1.4? Do I need additional drivers or other OS? I never had a 060 but many years ago I heard people complaining that not everything was working on 060 in comparision to 040..

  • 060 is indeed more complicated to install with the "classic" accelerators from the 1990s, but I'm aiming at making this completely smooth, so no additional software installation is required. My goal is to have all software in the flash ROM of the card, so it automatically comes with the correct libraries and won't crash due to the wrong libraries on your harddrive. I have licensed the required libraries from Thor for this. OS 3.1.4 should work fine with both 040 and 060 on the ACA1240/1260. Our test systems are running plain-3.1 for now.


    It's true that 060 is "less compatible" than previous processors, and that's due to a few commands not being implemented at all. These un-implemented commands require additional software to run in the background to catch such unavailable instructions and replace them with something that's 060-compatible. This piece of software will be in the flash ROM of the ACA1240/1260, so ideally, you'll only notice that the system is faster, but not less compatible.


    This may still mean that certain software won't run because it just does not expect such a fast CPU. You'll have slow-down and degrading options for that case, such as running the 040/060 at a slower speed, or switching back to the 68020 of your A1200, without removing the card from the trapdoor slot. In that case, the ACA1240/1260 will act a memory expansion to the A1200, or it can completely go into "stealth mode" for particularly piccy software.