EMC2 running on Raspberry Pi?

I am using a GUI without Gremlin code preview so I have little experience using the Pi with LinuxCNC+OpenGL. Some wild experiments with Kivy (GL-based GUI toolkit) worked fine though.

Did you try:

- Give the GPU some more RAM to work with (e.g. gpu_mem=256 in /boot/config.txt to allocate 256MB)
- Enable the OpenGL driver using raspi-config?

I tried all your suggestions.
- I increase gpu mem to 512 and it help maybe 5%
- Enabling opengl in raspi-config also not help

Has linuxcnc community any plans for support arm boards like Raspberry Pi or
Beaglebone?

viktan wrote:

Only thing that needs to be done to make linuxcnc run really well is for someone to make a wrapper library to allow python opengl use the rpi openGLES GPU.

Hi all,
I want to ask about opengl on Raspberry Pi
I use LinuxCNC on Raspberry Pi with our boards pidicnc. There is problem with graphic performance. When I loaded bigger code, the graphic performance and a response of whole linuxcnc is low while performance of RT tasks is OK. Here is video from my hobby mill:
www.dropbox.com/s/ugv7nkg3vxayqq0/VID_20170322_084927.mp4?dl=0
What do you think? It is caused by some setting or there is something bigger unsupported on arm platform?

We also talk about it on:
forum.linuxcnc.org/27-driver-boards/2974...trol-system?start=20

Any idea will be really helpful for me, because it is very restrictive for our product
Thanks Viktor

I very infrequent check my email but today find for some reason I am unknowingly subscribed to this thread?

Anyways I try to be polite, so can say I found last time I tried raspberry (pi2) the software opengl preview was acceptable (4 frames per second update).

I have tried other methods but it is more work than worth any return in order to get better speed results, POC was done on

gles backplot using pi3d which can run 70fps without effect step rate, but it require over 1000 hours code work for full integration (modularising the GL part of cannon to allow GL or gles skin for display) and testing probably take longer.

webgl interface using threejs works well but ws is not realtime (obviously not a problem for remote display but if this is vision feedback into RT then no chance), an almost feature complete web version of axis was created and hooks into glade gui builder were roughed out (dev time for full implement was put at about 200 hours per widget for the gladevcp python as remote web ws/js widgets)

The anholt driver looks like it will effect RT and gpio control in negative ways (this is not certain, but was general consensus from two people that looked at the code a year or more ago)

I would avoid the the raspberry pi if I was you, they are focused only to education and do not like commercial use of their subsidised system(this is my guess based on their general negative replies to my attempts at comunication and the fact that they banned me from their forum). I am currently trying to get board designers to create something for the nextgen robotics but althings involve people end in bad politics, but maybe there will be progress. Unfortunately soc design is expensive and without certain market no one that wants to avoid possible loss will invest.

We were also looking at cmm interface with rpi and had probems which were guessed at being due to the encoder manufacturer being part of the same HP conglomerate and therefore they did not want any market competition, if you are small maybe they do not care about your product but if you are cause them problem you will ind it very hard.

Despite this I still find myself buying their their products to play with as they seem the best engineered and price efficient on the market (though still terribly flawed in many ways), but I would not try to base a product on them as they offer no support and may well cause problems if you effect their keiretsu.


Apology for poor spelling and grammar this is quick post and NOT a legally binding contract, most is guess, hearsay(heresay?), paranoia(conspiracy theory), and joke, roughly based on upon what I have made from the reality within which I am trapped.


Any sufficiently advanced troll is indistinguishable from a genuine kook or the viewpoints of even the most extreme crank are indistinguishable from sufficiently advanced satire.

not sure if this thread is still in use. admittedly, i only read the first few pages.

I came across a new Raspberry Pi. it is at adafruit.com
www.adafruit.com/product/3442
the processor modules are down the page in the "May we also suggest" section. it has 120 GPIO pins, 1.2GHz proc, 1GB ram, and 4GB of onboard flash.

when i have the money, i will likely buy one, just to see what it is like, but i remembered this forum topic, and i wonder if it would be good to run LinuxCNC on. looks to me that the Rpi isn't just for kids anymore

anyway, i love LinuxCNC, and i can't wait to start and finish building my woodworking CNC router. so far all i have done is spin some cheap steppers (NEMA17) on my work-bench.

~Travis

So far I have little trouble running LinuxCNC on the Pi3, but then again, I am not yet done building the 3D-printer. Current state:



I did leave the Pi running LinuxCNC with motors attached on the bench for a couple of days, no issues, no following errors from the stepper drives (the L6470 chips track the stepper position and for LinuxCNC they act as velocity controlled servos), no USB communication errrors.
I do get a latency excursion here and there, but so far that causes no noticeable side effects.

Where did you get Linuxcnc for raspberry Pi? I have one from Machinekit community. Are you satisfied with his graphic performance?

I compiled a PREEMPT_RT kernel for the Pi3 by patching the Pi kernel sources with the RT patch from kernel.org, and on top of that I compiled LinuxCNC master. I could have used MachineKit as well, but I do not see the advantages of that project over LinuxCNC and I also have a CNC mill and lathe running on LinuxCNC.

I am not running a GUI with OpenGL preview (cannot fit that on the 800x480 Pi touchscreen), thus so far graphics performance is more than adequate.

If anyone is spending >$2000 on a CNC router + tooling (and it is hard to build something decent for that budget) I do not see the point of using a Pi for that. Once all the costs are added up, the extra cost of a conventional PC-based controller setup is peanuts. A suitable refurbisched PC costs $75 (or even new mainboard+memory+storage can be had for <$200), Mesa hardware is well build and not extremely expensive either and a couple of E-bay sourced Leadshine DM drives are doable as well.

For a 3D printer, diode laser cutter or people like me who like to play this is different. There even the Pi3+touchscreen+powersupply+memory card+L6470 stepper drives can be described as 'expensive', and size matters.

this little board could be an alternative to the raspi?
www.up-board.org/up/

The advantage of Raspberry Pi is not in its price but in its size. I think the performance of the latest version is more than enough to handle any cnc machine. It has a powerful CPU as well as a GPU and has interesting peripherals, especially SPI.

I work on universal boards based on FPGA for Raspberry Pi that can be controlled from any program that can communicate with the SPI port. One of the uses is LinuxCNC.

I do not see the meaning of Machinekit and I would rather use Linuxcnc. Would it be possible to share the Linuxcnc disk image or make a more detailed procedure to how compile it?

Boards like that Up^2 sound really good to me. But like others such as the Udoo x86 they are still in preorder or just very expensive.

Regarding LinuxCNC on the Pi3: my SD image contains too much 'experimental stuff' to be able to safely hand it over. My Pi is used to all that misuse, but yours probably burst in flames

However, I can try to build .deb packages for the kernel. Never did it before, so no idea how complicated it is.
In the meantime you can get a working realtime kernel from www.frank-durr.de/?p=203
That kernel works fine, it only lacks support for the Pi3 WiFi. This is why I took the Pi foundation kernel sources and patched it with the closest matching PREEMPT_RT patch. Building and installing the Pi kernel is described here: www.raspberrypi.org/documentation/linux/kernel/building.md

Building LinuxCNC is described here: linuxcnc.org/docs/devel/html/code/building-linuxcnc.html
Once you get to the ./configure step, make sure to use ./configure --with-realtime=uspace.