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Hardware Hacking Businesses Open Source Hardware

Own An Open Source RISC-V Microcontroller (crowdsupply.com) 101

"Did you ever think it would be great if hardware was open to the transistor level, not just the chip level?" writes hamster_nz, pointing to a new Crowd Supply campaign for the OnChip Open-V microcontroller, "a completely free (as in freedom) and open source 32-bit microcontroller based on the RISC-V architecture." hamster_nz writes: With a completely open instruction-set architecture and no license fees for the CPU design, the RISC-V architecture is well positioned to take the crown as the 'go to' design for anybody needing a 32-bit in their silicon, and Open-V are crowd-sourcing their funding for an initial manufacturing run of 70,000 chips, offering options from a single chip to a seat in the design review process. This project is shaping up to be a milestone for the coming Open Source Silicon revolution, and they are literally offering a seat at the table. Even if you don't end up backing the project, it makes for very interesting reading.
Their crowdfunding page argues "If you love hacking on embedded controllers, breaking down closed-source barriers, having the freedom to learn how things work even down to the transistor level, or have dreamed of spinning your own silicon, then this campaign is for you."
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Own An Open Source RISC-V Microcontroller

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  • EditorDavid (Score:5, Insightful)

    by subk ( 551165 ) on Saturday November 26, 2016 @07:39PM (#53367611)
    Thanks, EditorDavid, for the welcomed break in leftist propaganda posts that don't matter to nerds.
    • What exactly happened here? Suddenly, we have stopped discussing the latest adventures of Trump, Clinton, fake news, Jill Stein and are suddenly discussing things like microcontroller HDLs? I thought that those things were germane to this site 4 years ago, if not more

      • Sad for you if you don't understand that politics affects technology.

        • by Anonymous Coward

          Sad for you if you don't understand that politics affects technology.

          So does constipation, and Swifties clogging the pipes. We need more plunger stories like this.

      • by dbIII ( 701233 )
        Due to the those events you may have to learn Mandarin to read techie goodness.
        At least that's what those who are panicking are thinking hence all the articles. Who the fuck knows what Trump is going to try.
    • leftist propaganda posts

      On /.? As a European, let me say "hahaha".

    • It's still propaganda:

      the RISC-V architecture is well positioned to take the crown as the 'go to' design for anybody needing a 32-bit in their silicon

      In whose reality is that going to happen? You've got entire industry branches that exist around building and supporting long-established 32-bit architectures, anything you want from any vendor, and we're supposed to believe that a proof-of-concept run of a handful of CPUs with little to no widespread acceptance and support is now the way to go? I mean, good on them for doing it, it's a cool project, but lets be realistic about how its going to play out.

  • overpriced. (Score:5, Insightful)

    by Gravis Zero ( 934156 ) on Saturday November 26, 2016 @08:01PM (#53367695)

    I love RISC-V, I really do but $50 for a chip in bad package is too much. Who can hand solder QFN chips?! $20 is really my limit for a chip of that caliber and it would need to at least be in a QFP package.

    The reason stated for the QFN package was to achieve clock higher frequencies (160MHz) but really, 50MHz is enough.

    • The reason stated for the QFN package was to achieve clock higher frequencies (160MHz) but really, 50MHz is enough.

      If you're into this stuff, you probably already have a suitable FPGA board that gets closer to 160 than 50 MHz.

    • Re:overpriced. (Score:5, Informative)

      by ShanghaiBill ( 739463 ) on Saturday November 26, 2016 @08:41PM (#53367835)

      Who can hand solder QFN chips?!

      Get a tube of solder paste (good old PbSn, not RoHS) and a $29 toaster oven from Walmart for reflow.

      Pro-tip: Use a different toaster oven for grilled cheese sandwiches.

      • Or just get some skills. I hand soldered several QFN chips with an incredibly small pitch during my thesis. Simple tips:

        - Use very liberal amounts of flux.
        - Ensure the solder mask gives you enough space to place your iron, the solder will wick up to the pins.
        - Solder down 2 opposite pins
        - Check that all pins line up after soldering down the first 2.
        - Check them again.
        - No seriously did you check them? Use a magnifying glass or a microscope. This is your last chance before you royally screw things up.
        - Use t

    • by c ( 8461 )

      $50 for a chip in bad package is too much

      Eh?

      $50 for a first run chip, which they're billing as a collectable.

      Looking at the other tiers that have the dev board, the per-chip price ranges from $3 and $10. Which still seems a bit high (I think the STM32's are around $1 each), but it's nothing like $50.

    • I love RISC-V, I really do but $50 for a chip in bad package is too much. Who can hand solder QFN chips?! $20 is really my limit for a chip of that caliber and it would need to at least be in a QFP package.

      The reason stated for the QFN package was to achieve clock higher frequencies (160MHz) but really, 50MHz is enough.

      As is 640k obviously.

    • by c4757p ( 4213341 )

      Who can hand solder QFN chips?!

      Who can't? FFS, they're one of the easiest packages to solder. Grab a firestick and practice...

    • QFNs aren't that hard to solder. They've got lands up the side, so you can even do them with a normal soldering iron. I've never tried that personally, but I've watched others do it. The technique is similar to the blob and suck medhod of doing fine pitch leaded packages. I have however reworked and replaced DFNs and small LGAs with one of those cheapie 852D air guns off ebay. And I've also soldered them with a $10 stencil and a basic reflow oven.

      I hear other people use a cheap toaster oven rather than spen

    • At least a QFN can be hand soldered. There are packages that are literally impossible to hand solder, like a BGA.
  • My personal view is that most western societies seem to be on a trajectory of ever closed groups, while the hardware we live on seems to be becoming more and more open.
    • by Anonymous Coward

      Your view is wrong. Hardware has only gotten more closed with time.

      It used to be the case that the computer you bought came with schematics and a document describing how to program the thing to do whatever you wanted. Now, you're lucky if you can get someone in the depths of a block-box corporation even to acknowledge that there's a bug in the software or hardware.

  • This will get really fun the day someone manages to make an CPU on his own garage.
    I hope this person documents it on the net with videos etc..

    • by cruff ( 171569 )

      This will get really fun the day someone manages to make an CPU on his own garage.

      Might be hard with the birds landing in the middle of the clean room. :-)

      • Does it have to be small and electronic?

        If I had the time and money, I could make a pneumatic version of the PDP8 in a garage (live in London, and cannot currently afford a garage). It would be about the same size as a PDP8/S and might even go as fast! (Using 8E architecture). Read/write paper tape only - no pneumatic TU56's!

        PDP8 architecture was open source. I think the PDP11/20 was too. I believe Sparc is also open source, even Sparc64, although actual processors like Sun/Oracle/Fujitsu's are not becaus

    • This will get really fun the day someone manages to make an CPU on his own garage.

      That day is in the past, not the future. Some early cpus were taped out, etched, and metallized by hand. Today, you need nano-scale photolithography and a multi-billion dollar fab. You can load this CPU into an FPGA, but if you want it directly in silicon, you ain't gonna do that in no garage.

      • This will get really fun the day someone manages to make an CPU on his own garage.

        That day is in the past, not the future. Some early cpus were taped out, etched, and metallized by hand. Today, you need nano-scale photolithography and a multi-billion dollar fab. You can load this CPU into an FPGA, but if you want it directly in silicon, you ain't gonna do that in no garage.

        Today, you need to set your expectations and hopes realistically. If it could be done in the past, it can be done today. You will just have to have expectations of utility more in line with what the folks in the past had, rather than what you might wish for with knowledge of today's commercial tech.

        Set your sights towards a raspberry pi or less, not towards modern high performance products. At least for the start. It may well be that once you get the thin end of the wedge / foot in the door, you can s

        • Today, you need to set your expectations and hopes realistically ... a raspberry pi or less

          A Raspberry Pi has more transistors than a top end 1980s supercomputer. It is a million times more complex than anything you could ever hope to etch in a garage. Maybe you could do a 4004 (~2000 transistors) with tape and etchant, but a Raspberry Pi has billions.

          • Didn't they make 4004s with tape and etchant at the "real" factory?

            • The photomasks were taped out originally, but it was still a 10 um photolithographic process (huge by today's standards) on a very tiny die that required a lot of specialized equipment. It's possible to make individual discrete components (transistors, fundamental logic gates) yourself, but a die with thousands of transistors on it is still a bit beyond the DIY crowd.
              • True - it was a guided missile chip - small was a virtue.

                I'd bet that by now, some sod somewhere has put together a 4004 with discrete transistors on breadboards.

  • by CaptainDork ( 3678879 ) on Saturday November 26, 2016 @08:35PM (#53367809)

    ... and a sea story:

    A fairy tale starts with, "Once upon a time ... "

    A sea story; "Hey, this ain't no shit ... "

    So, this ain't no shit:

    When I trained on electronics in this man's Navy in 1965, I went to NAS Memphis and we worked on a vacuum tube computer that filled up a whole wall. We'd open the windows in the winter because it was HOT in there.

    There were two tubes per flip-flop module. The tubes burned out often and we'd have to troubleshoot that.

    Our goal was to use a row of toggle switches to turn lights "on" for a binary one, and "off" for a binary zero.

    We would load up one register with four bits and the only other register with four bits and then we'd press a switch that could only execute an add and we'd better get the right binary number on the third row of lights.

    We started (I shit you not) all of our algebra, trig, geometry, etc. including square root extraction by pencil and paper and then moved into the slide rule age.

    The only goddam transistors we saw were the 9-volt radios playing Elvis.

    • So, could the guys on the tube computer get a firing solution any faster, or more accurately, than the guys with the slide rules?

      • No firing solutions by any means.

        We were avionics, not ordinance.

        The tube "computer" added two 4-bit numbers.

        That was it.

        --

        The first real computer I saw was the Jezebel made by Magnavox to hunt submarines. $250,000 with one aboard a Grumman twin prop job off a carrier and two installed in P3 Orions (of hurricane fame).

        It had a ferrite core, little iron rings with two wire going through them. When the current went one way, the magnetic field was a "one" and when the current through another wire, the core was

  • by cjameshuff ( 624879 ) on Sunday November 27, 2016 @07:48AM (#53370687) Homepage

    The high speed is because they currently don't have any on-chip flash (flash being slower to access than SRAM, and typically being what slows 32-bit microcontrollers down). That means this isn't a single-chip solution like most microcontrollers, though they are working on changing that.

    Instead of flash, they store their program in the same SRAM used to store data (which makes that 8 kB of SRAM a lot more limiting than it would be on a Cortex M0 with the same amount of SRAM plus 16-256 kB flash). Most microcontrollers use a Harvard architecture with separate program and data memory, allowing instructions to be fetched from flash while performing reads from and writes to SRAM. If they don't do this, I wonder what sort of performance they'll see when they have to make regular reads from a slow flash memory in between SRAM accesses. Or will they just load the entire program into SRAM? That's not going to be ideal in terms of power consumption, requiring a much bigger memory array than they'd otherwise use, something that's going to get worse as they try to compete with larger microcontrollers.

    Also, the Harvard architecture has some advantages in security: things can be set up so a very specific sequence of actions has to be performed to enable writing to program memory. With IoT devices, this sort of thing is becoming more important...not an issue at present, with their 8 kB memory, but something to consider when thinking about this thing's future.

    • Double-gate (EEPROM) is expensive by license and by fabrication. We are diving deep to solve this, by doing an extra effort on designing our own NVRAM cells (single poly) and try to virtualize RAM with the limited NVRAM possible. NVRAM is area expensive and if we reach the goal of $500k plus an additonal $200k you would see speed that you cannot see on regular micros. This is the reason of open source, work around things and do better than closed commercial chips.
  • Analyzing the RISC-V Instruction Set Architecture [adapteva.com] â" Andreas Olofsson, August 2014

    The RISC-V architecture is not revolutionary, but it is an excellent general purpose architecture with solid design decisions. The true breakthrough here is really the open source licensing model and the maturity of the design as compared to most other open source hardware projects. ... A royalty free 64-bit RISC-V core would have a raw silicon cost of a couple of cents in current CMOS process nodes. Now that is exciting!

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