For those interested, I've been in comms with the author of Remora and he has this working. He's been using it on a 3D printer but once setup, I would think it's a configuration task to set it up to run a 4 axis CNC, a 2/3 axis laser cutter, etc.
On Thursday, February 18, 2021 at 2:44:47 PM UTC-8 Joonas wrote: > Realtime isn't about latency but determinism and the standard usb driver > stack is non-deterministic. I believe there are realtime capable stacks for > usb devices but it needs to be supported by both devices. And I don't think > most mcus support it. > > If you don't care about the smoothness of tour motion or use a buffered > approach, usb works fine. > > On Fri 19. Feb 2021 at 0.36, justin White <blaz...@gmail.com> wrote: > >> It's not that simple. USB2 has higher latencies, true, but if you are OK >>> with them, then the USB2 interface is as capable of real-time communication >>> as any other interface. There have been attempts to mitigate these >>> latencies with various results. (Search research papers online.) USB3 >>> should be much better in this regard. >>> >> >> I dont see how that's true when the default USB2 polling rate is 8ms. You >> can change the mouse driver to get 1ms but I don't know that the RT patches >> touch USB. So whats the secret sauce to getting RT USB if the polling >> interval remains at 8ms on a shared bus? >> >> USB3 isn't really even worth talking about yes its peer to peer with much >> better latency but an rpi4 having a USB3 port doesn't do any good when MCUs >> really do not. Most MCUs bake usb2 hardware right onto the chip while usb3 >> is generally a PCIE lane attached to a PHY which I have yet to see on any >> dev boards. >> >> So what's the secret sauce to RT USBx? And .......why, when any MCU >> contains fast UARTs, spi and sometimes ethernet. >> >> On Thu, Feb 18, 2021 at 11:23 AM cern via Machinekit < >> machi...@googlegroups.com> wrote: >> >>> Hello, >>> >>> Feb 18, 2021, 14:32 by joonas....@gmail.com: >>> >>> > USB itself isn’t realtime capable so it can’t be used for any realtime >>> tasks. >>> > >>> It's not that simple. USB2 has higher latencies, true, but if you are OK >>> with them, then the USB2 interface is as capable of real-time communication >>> as any other interface. There have been attempts to mitigate these >>> latencies with various results. (Search research papers online.) USB3 >>> should be much better in this regard. >>> >>> Cern. >>> >>> > >>> > On Thu 18. Feb 2021 at 11.18, > ozzy...@gmail.com> <> >>> ozzy...@gmail.com> > wrote: >>> > >>> >> Be interesting to see more details on the Linuxcnc\USB\MESA setup. >>> >> As far as I was aware there was no RT support for USB. >>> >> I'm not even sure if MESA themselves recommend their USB boards for >>> use with Linuxcnc. >>> >> >>> >> On Thursday, February 18, 2021 at 7:32:57 AM UTC+11 >> >>> doug....@gmail.com>> wrote: >>> >> >>> >>> Great, thanks for finding it! >>> >>> >>> >>> I've seen lots of people purchasing 3DP controller boards to upgrade >>> 3DP/Lasers/CNC's(consumer stuff) and many of them also use an rPi with >>> OctoPrint or CNCjs, GridBot etc. >>> >>> I like this approach in that all of my macines(4 3DPs, 2 laser >>> cutters and 1 CNC) all have consumer grade controllers in them running on >>> different uCPUs. Some AVR328, STM32, LPC17xx and one a BBB/CRAMPS. >>> >>> But would love to be able to have LinuxCNC/Machinekit on an rPi >>> doing the control, UI, setup. >>> >>> On Wednesday, February 17, 2021 at 11:02:18 AM UTC-8 >>> >>> ce...@tuta.io <>>>> wrote: >>> >>> >>> >>>> Hi, >>> >>>> the code is available in >>>> >>> https://github.com/scottalford75/Remora>>>> - looks like he though >>> that spiPRU is not a great name and changed it to something more flashy. >>> >>>> >>> >>>> Looks interesting from programming point of view, but I wonder how >>> many people would buy Smoothieboard and RPi both to run 3D printer with >>> LinuxCNC on it? Most will stay with Smoothie, I think. >>> >>>> >>> >>>> Cern. >>> >>>> >>> >>>> Dne úterý 16. února 2021 v 19:18:20 UTC+1 uživatel >>>> >>> doug....@gmail.com <>>>>> napsal: >>> >>>> >>> >>>>> I was about to start on setting up a Xylotex BareBoneCNC with a >>> BBB/Machinekit and thought I'd look at what's going on with Raspberry Pi in >>> CNC world. I found a video of a guy driving a Mesa board over USB with >>> LinuxCNC and it looked impressive(doesn't take much). >>> >>>>> >>> >>>>> Got to wondering if a standard 3DP controller like SKR, >>> Smoothieboard, etc couldn't run firmware similar to the MESA board and only >>> found mention of this spiPRU but no details, code, anything. >>> >>>>> >>> >>>>> https://github.com/scottalford75/LinuxCNC-on-RPi >>> >>>>> >>> >>>>> I searched for spiPRU here and in general inter-web lands and >>> found nothing but the mention of it in the above git repo. If anyone knew >>> about it I figured they would be here. >>> >>>>> Thx >>> >>>>> >>> >> >>> >> >>> >> >>> >> -- >>> >> website: >> http://www.machinekit.io>> blog: >> >>> http://blog.machinekit.io>> github: >> https://github.com/machinekit >>> >> --- >>> >> You received this message because you are subscribed to the Google >>> Groups "Machinekit" group. >>> >> To unsubscribe from this group and stop receiving emails from it, >>> send an email to >> machinekit+...@googlegroups.com>> . >>> >> To view this discussion on the web visit >> >>> https://groups.google.com/d/msgid/machinekit/cc241b97-47bb-48d0-b3b4-e595dc809b55n%40googlegroups.com >>> >>> < >>> https://groups.google.com/d/msgid/machinekit/cc241b97-47bb-48d0-b3b4-e595dc809b55n%40googlegroups.com?utm_medium=email&utm_source=footer>>> >>> >>> . >>> >> >>> > -- >>> > Terv, >>> > Joonas Forsell >>> > >>> > >>> > >>> > -- >>> > website: > http://www.machinekit.io> blog: > >>> http://blog.machinekit.io> github: > https://github.com/machinekit >>> > --- >>> > You received this message because you are subscribed to the Google >>> Groups "Machinekit" group. >>> > To unsubscribe from this group and stop receiving emails from it, >>> send an email to > machinekit+...@googlegroups.com> . >>> > To view this discussion on the web visit > >>> https://groups.google.com/d/msgid/machinekit/CA%2B%2BSnhq%3D-rmGD2z8ewbQ9ryBoyWgwymJTbmWp6NKnGPyhmsrbw%40mail.gmail.com >>> >>> < >>> https://groups.google.com/d/msgid/machinekit/CA%2B%2BSnhq%3D-rmGD2z8ewbQ9ryBoyWgwymJTbmWp6NKnGPyhmsrbw%40mail.gmail.com?utm_medium=email&utm_source=footer>> >>> >>> . >>> > >> >> >>> >>> -- >>> website: http://www.machinekit.io blog: http://blog.machinekit.io >>> github: https://github.com/machinekit >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Machinekit" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to machinekit+...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/machinekit/MTpwssk--3-2%40tuta.io. >>> >> -- > Terv, > Joonas Forsell > -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. 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