Re: [Emc-users] Stepper, ideal pulses without feedback

> Nicklas, when I built a pcb drilling machine some years ago, I found > constant acceleration and deceleration to top speed worked best, as > for the most part trying to go instantly to the maximum speed the > motors are capable of results in lost steps. > You will need a bit of experimentation

Re: [Emc-users] Linuxcnc on arm

RTAI patches the kernel with an interrupt pipeline and handler that can take over real time interrupts but drivers can still interfere with it. Things used to be worse. Especially with integrated GPU's. We did lots of RTAI development over the past few years and we had difficulty building

Re: [Emc-users] Linuxcnc on arm

Hi, I think Raspberry Pi Module 3 is a good choice, I'll try it when I get a board soon. Regards, Yanjun Luo. 2016-03-16 23:25 GMT+08:00 bari : > The i.mx6 can easily run Linuxcnc. The issues that you'll run into are > the high cost of the i.mx6 boards and getting the GUI

[Emc-users] Stepper, ideal pulses without feedback

I am planning to use a micro controller for stepper step pulse generation. I have considered to use an inverter card but special purpose stepper circuits are cheap so I use one of these instead. It should be possible to feed timer values then toggle should happen via DMA timer output compare

Re: [Emc-users] Q re these Chinese 3 phase motors.

On Thursday 17 March 2016 22:57:06 Gene Heskett wrote: Ping? > Greetings; > > This one is a 1.5 horse, 8 amps nameplate rating, air cooled which at > low speed isn't goping to work at all well anyway, and at 20 Hz drive > I am quite dissapointed in its torque, 3 or 4 oz/in when the torque > boost

Re: [Emc-users] Stepper, ideal pulses without feedback

> Hi Nicklas, > > it should be fine to keep the step rate (velocity) constant between > updates from the trajectory planner, assuming that it runs at something > like 1kHz and the machine is not highly dynamic. Limiting velocity and > acceleration in the step generator should generally not hurt

Re: [Emc-users] Stepper, ideal pulses without feedback

It could be a good option so I do not need to have a large computer for a small machine. As is know it is more a question about how to ideally increases/decrease step rate for a stepper motor? On Fri, 18 Mar 2016 16:05:31 -0400 John Alexander Stewart wrote: > Just FYI -

Re: [Emc-users] Linuxcnc on arm

Wow, 25% more expensive. :/ http://www.shop.cncmonster.de/LinuxCNC/FPGA-Karten/USB/Parallelport/7I90HD-Parallel-SPI-Anything-I-O-card::393.html?MODsid=ab1fd9c2053920f289f27a2a6c15f815 Do you know some cheaper offers on this side of the pond? On 2016-03-16 17:33, andy pugh wrote: > On 16 March

Re: [Emc-users] Linuxcnc on arm

But see here's where I'm confused. If Linux already provides priorities of tasks: http://www.thegeekstuff.com/2013/08/nice-renice-command-examples/ then the LinuxCNC as a task can run higher than anything else. If the motion/encoder control is offloaded to a device driver, which should have even

Re: [Emc-users] Linuxcnc on arm

On 2016-03-16 17:33, andy pugh wrote: > On 16 March 2016 at 16:20, W. Martinjak wrote: >>> http://store.mesanet.com/index.php?route=product/product=83_85_id=291 >> Can you point me to the spec of the spi protocoll of this card? >> Or the source? > The spec is in the manual:

Re: [Emc-users] Linuxcnc on arm

On 2016-03-16 17:50, John Dammeyer wrote: >> -Original Message- >> From: Peter C. Wallace [mailto:p...@mesanet.com] >>> The ARMs and current crop of PCs are orders of magnitude faster and more >>> powerful so why is it that the real time part of Linux isn't the defacto >>> standard for

[Emc-users] Q re these Chinese 3 phase motors.

Greetings; This one is a 1.5 horse, 8 amps nameplate rating, air cooled which at low speed isn't goping to work at all well anyway, and at 20 Hz drive I am quite dissapointed in its torque, 3 or 4 oz/in when the torque boost is disabled. I can stop and hold it between thumb and forefinger

Re: [Emc-users] Linuxcnc on arm

On Wed, 16 Mar 2016 13:22:48 +0100 Philipp Burch wrote: > Hi Erik, > > as far as I know, MachineKit is a fork of LinuxCNC designed to run on > ARM platforms: > http://www.machinekit.io/ > > Bye, > Philipp > > On 16.03.2016 13:17, Erik Friesen wrote: > > I have been doing some

Re: [Emc-users] Linuxcnc on arm

On 16 March 2016 at 16:20, W. Martinjak wrote: > >> http://store.mesanet.com/index.php?route=product/product=83_85_id=291 > Can you point me to the spec of the spi protocoll of this card? > Or the source? The spec is in the manual:

Re: [Emc-users] Stepper, ideal pulses without feedback

Just FYI - about a year ago or so I purchased from Jeff @xylotex a BBBlack and DB-25 cape - ran my Unimat SL CNC'd lathe just fine (feeding a spare Gecko G540, 2 axes of which were unused) BBBoard from Xylotex came with LinuxCNC Machinekit on a little SDCard. An out of the box solution. On

Re: [Emc-users] Linuxcnc on arm

On 2016-03-16 17:10, andy pugh wrote: > SPI works well and in conjunction with an FPGA/CPLD very well. > That might be an interesting setup with: > http://store.mesanet.com/index.php?route=product/product=83_85_id=291 > Yep. Can you point me to the spec of the spi protocoll of this card? Or the

[Emc-users] Linuxcnc on arm

I have been doing some work with an i.mx6 of late, and wonder why the quad couldn't do linuxcnc? It seems there is some obscure reason I read somewhere. Older Haas machines use the 68040? 40mhz clunker. This got me thinking, anyway http://nxgencnc.com/ But I ended up buying a 1996 haas. Going

Re: [Emc-users] Stepper, ideal pulses without feedback

On 19.03.2016 20:20, Nicklas Karlsson wrote: >> Hi Gene! >> >> On 19.03.2016 19:24, Gene Heskett wrote: >>> [...] >>> >>> In 1978 I needed to generate an academy countdown leader, 9.9 to 1.9 >>> seconds until 1st video, on an RCA 1802 processor, which has built in >>> dma. This thing ran at the

Re: [Emc-users] Linuxcnc on arm

It only sort of does. If a kernel or X dev decides to access hardware directly to get his project done he probably will. Unfortunately there is no kernel police and no really agreed upon rules that they explicitly follow. On 03/16/2016 12:10 PM, John Dammeyer wrote: > But see here's where I'm

Re: [Emc-users] Linuxcnc on arm

> But see here's where I'm confused. If Linux already provides priorities of > tasks: > http://www.thegeekstuff.com/2013/08/nice-renice-command-examples/ > then the LinuxCNC as a task can run higher than anything else. > If the motion/encoder control is offloaded to a device driver, which should

Re: [Emc-users] Linuxcnc on arm

On Sat, Mar 19, 2016 at 12:08 PM, Nicklas Karlsson < nicklas.karlsso...@gmail.com> wrote: > On Sat, 19 Mar 2016 13:50:22 -0400 > Gene Heskett wrote: > > > I am thinking about split in two with real time threads on micro > controller and the computer for the user interface. It

[Emc-users] Spam

Greetings all; I use mailfilter in front of fetchmail, which looks at the incoming email while its still on the server & before fetchmail gets to see it, and I am finding a huge advantage in all the new .tld's they have issued, as its possible to nuke a whole category of spam in just two lines

Re: [Emc-users] Linuxcnc on arm

> So how is that different from a non pre-emptive RTOS kernel? > > My understanding, and it's very superficial, is that the real time component > of linux puts a scheduler in front of the basic LINUX kernel. So now the > micro-stepping or DC-Servo/encoder support can get predictable low latency

Re: [Emc-users] Stepper, ideal pulses without feedback

On Sat, 19 Mar 2016 14:24:23 -0400 Gene Heskett wrote: > On Saturday 19 March 2016 13:23:27 Nicklas Karlsson wrote: > > > On Sat, 19 Mar 2016 09:52:55 -0700 > > > > Chris Albertson wrote: > > > On Fri, Mar 18, 2016 at 11:46 AM, Nicklas Karlsson < >

Re: [Emc-users] Stepper, ideal pulses without feedback

On Saturday 19 March 2016 14:40:42 Philipp Burch wrote: > Hi Gene! > > On 19.03.2016 19:24, Gene Heskett wrote: > > [...] > > > > In 1978 I needed to generate an academy countdown leader, 9.9 to 1.9 > > seconds until 1st video, on an RCA 1802 processor, which has built > > in dma. This thing ran

Re: [Emc-users] Linuxcnc on arm

On Sat, 19 Mar 2016 13:50:22 -0400 Gene Heskett wrote: > On Saturday 19 March 2016 13:08:43 bari wrote: > > > All of memleak's work on RTAI the past few years (which is now RTAI 5 > > without a single credit) was done on AMD hardware made in the past 7 > > years. > > No

Re: [Emc-users] Linuxcnc on arm

On Wednesday 16 March 2016 12:50:33 John Dammeyer wrote: > Seems that's a fault of the graphics drivers and their implementation. > The whole point of an RTOS is that tasks can run at priorities that > serve their needs. How would placing the video at a higher priority > be any different than

Re: [Emc-users] Stepper, ideal pulses without feedback

Hi Gene! On 19.03.2016 19:24, Gene Heskett wrote: > [...] > > In 1978 I needed to generate an academy countdown leader, 9.9 to 1.9 > seconds until 1st video, on an RCA 1802 processor, which has built in > dma. This thing ran at the smoking clock speed of 1.79 Mhz, but a full > processor

Re: [Emc-users] Stepper, ideal pulses without feedback

On Saturday 19 March 2016 13:23:27 Nicklas Karlsson wrote: > On Sat, 19 Mar 2016 09:52:55 -0700 > > Chris Albertson wrote: > > On Fri, Mar 18, 2016 at 11:46 AM, Nicklas Karlsson < > > > > nicklas.karlsso...@gmail.com> wrote: > > > I am planning to use a micro

Re: [Emc-users] Linuxcnc on arm

Linuxcnc 2.7 configured for "uspace" realtime builds and runs on x86, x86_64 and arm. our master branch even builds on 64-bit arm. However, it needs to be paired with a preempt-rt kernel (which generally only gets latency low enough for servo-cycle-only designs with smart I/O) and each

Re: [Emc-users] Linuxcnc on arm

Here's my take, which may be as old and tired as I am. The real issues in RT vs. not RT is not one of standard process scheduling. There are many knobs and hooks that can control that. The real problem is in the kernel and drivers, where you can and often have to lock out interrupts. If those are

Re: [Emc-users] Linuxcnc on arm

I am using the embeddedarm ts4900, seems more industrialized than the beagle/rasberi pi solutions. Plus, you can get answers on the phone in a pinch. The buck tends to stop nowhere with the rasberi solutions. My first go around was with the RiotBoard, which would randomly refuse to boot. On

Re: [Emc-users] Linuxcnc on arm

On Saturday 19 March 2016 13:08:43 bari wrote: > All of memleak's work on RTAI the past few years (which is now RTAI 5 > without a single credit) was done on AMD hardware made in the past 7 > years. No credits? 'Scuse me but thats not excusable, PM needs to understand TANSTAAFL. > > Every bit

Re: [Emc-users] Stepper, ideal pulses without feedback

I have seen and run machinekit, it is linuxcnc. I have also read about BeagleBone. There are plenty of devices suitable to generate the pulses but at which rate should pulses generated? Constant acceleration between different speeds? On Fri, 18 Mar 2016 12:50:21 -0700 "John Dammeyer"

Re: [Emc-users] Stepper, ideal pulses without feedback

On Sat, 19 Mar 2016 09:52:55 -0700 Chris Albertson wrote: > On Fri, Mar 18, 2016 at 11:46 AM, Nicklas Karlsson < > nicklas.karlsso...@gmail.com> wrote: > > > I am planning to use a micro controller for stepper step pulse generation. > > I have considered to use an

Re: [Emc-users] Stepper, ideal pulses without feedback

On Saturday 19 March 2016 12:52:55 Chris Albertson wrote: > On Fri, Mar 18, 2016 at 11:46 AM, Nicklas Karlsson < > > nicklas.karlsso...@gmail.com> wrote: > > I am planning to use a micro controller for stepper step pulse > > generation. I have considered to use an inverter card but special > >

Re: [Emc-users] Linuxcnc on arm

All of memleak's work on RTAI the past few years (which is now RTAI 5 without a single credit) was done on AMD hardware made in the past 7 years. Every bit of AMD silicon we touched ran under 25uS on the latency test. Just for fun we had a few tweaked <4uS max jitter. IME can't be turned off

Re: [Emc-users] Linuxcnc on arm

On Saturday 19 March 2016 10:35:07 bari wrote: > One more thing I forgot to mention that can add to poor real time > performance on x86 is BIOS/firmware. Intel has forced the use of their > Intel Management Engine that allows for remote control, phone home, > backdoor etc and operates completely

Re: [Emc-users] Stepper, ideal pulses without feedback

On Fri, Mar 18, 2016 at 11:46 AM, Nicklas Karlsson < nicklas.karlsso...@gmail.com> wrote: > I am planning to use a micro controller for stepper step pulse generation. > I have considered to use an inverter card but special purpose stepper > circuits are cheap so I use one of these instead. It

Re: [Emc-users] Linuxcnc on arm

Wow, 6 weeks after I asked this question on the devel-list https://sourceforge.net/p/emc/mailman/message/34817886/ and irc http://tom-itx.no-ip.biz:81/~tom-itx/irc/logs/%23linuxcnc-devel/2016-02-03.html#10:00:50 there is suddenly an answer. And without chunk on the user-list. What I've done

Re: [Emc-users] Stepper, ideal pulses without feedback

Nice box and standard port is always good, I should think about it. Steppers are for an xyz engraver so it is essentially a mini CNC machine without tool changer. On Fri, 18 Mar 2016 12:00:55 -0700 "John Dammeyer" wrote: > You are welcome to look at my Electronic

Re: [Emc-users] Linuxcnc on arm

And there are some that do both 1 *AND* 2. Look at the Xilinx Zynq for example. Dual gigahertz A9 cores w/ a FPGA core (Spartan/Virtex) that IIRC is larger than the one used for the Mesa 5i25. Could run a zillion channels of PWM or even hostmot2. We were porting some code to it for a work

Re: [Emc-users] Linuxcnc on arm

On 03/16/2016 07:22 AM, Philipp Burch wrote: > Hi Erik, > > as far as I know, MachineKit is a fork of LinuxCNC designed to run on > ARM platforms: > http://www.machinekit.io/ > > Yes, it is basically LinuxCNC as far as the user would see, but has a number of extensions underneath. But, it

Re: [Emc-users] Linuxcnc on arm

One more thing I forgot to mention that can add to poor real time performance on x86 is BIOS/firmware. Intel has forced the use of their Intel Management Engine that allows for remote control, phone home, backdoor etc and operates completely out of band. So you'd never notice it unless you

Re: [Emc-users] Linuxcnc on arm

As I understand it, the MachineKit was forked from an earlier version of LinuxCNC and LinuxCNC requires a real time kernel to run. Why is it that the real time kernel hasn't become a basic part of Linux so that the orphan Linux is the one without the kernel? Surely by now we've moved past the

Re: [Emc-users] Linuxcnc on arm

> -Original Message- > From: Peter C. Wallace [mailto:p...@mesanet.com] > > > > The ARMs and current crop of PCs are orders of magnitude faster and more > > powerful so why is it that the real time part of Linux isn't the defacto > > standard for Linux. If it were wouldn't the latest

Re: [Emc-users] Linuxcnc on arm

That's why I think the other direction and put the real time stuff on a micro controller, there are no graphic drivers to think about. I think it is the motion-command-handler and motion-controller threads. I expect bandwidth required to communicate with the GUI would be rather low. With real

Re: [Emc-users] Linuxcnc on arm

> On 03/16/2016 11:50 AM, John Dammeyer wrote: > > Seems that's a fault of the graphics drivers and their implementation. The > > whole point of an RTOS is that tasks can run at priorities that serve their > > needs. How would placing the video at a higher priority be any different > > than an

Re: [Emc-users] Rewire Question?

I'm not sure if it is against code or not (I would be surprised if it is not), but I would run some new conduit. Separating phases like that is a really bad idea and conduit is really cheap. Dave On 3/16/2016 12:26 PM, Todd Zuercher wrote: > Bringing back an older thread. Went to start

Re: [Emc-users] Linuxcnc on arm

On 2016-03-16 16:41, andy pugh wrote: > On 16 March 2016 at 15:35, Yanjun Luo wrote: >> Hi, >> I think Raspberry Pi Module 3 is a good choice, I'll try it when I get a >> board soon > The problem with the Pi is that the obvious choice for IO, Ethernet, > is connected via

Re: [Emc-users] Linuxcnc on arm

Real time is not one of the main concerns of the kernel devs. The kernel has graphics drivers that interfere with real time as well as X. On 03/16/2016 11:24 AM, John Dammeyer wrote: > As I understand it, the MachineKit was forked from an earlier version of > LinuxCNC and LinuxCNC requires a

Re: [Emc-users] Linuxcnc on arm

On 16 March 2016 at 15:52, W. Martinjak wrote: >> The problem with the Pi is that the obvious choice for IO, Ethernet, >> is connected via the USB bus. >> > > But SPI works well and in conjunction with an FPGA/CPLD very well. That might be an interesting setup with:

Re: [Emc-users] Linuxcnc on arm

Seems that's a fault of the graphics drivers and their implementation. The whole point of an RTOS is that tasks can run at priorities that serve their needs. How would placing the video at a higher priority be any different than an non-real time system that allows the video to run to completion.

Re: [Emc-users] Linuxcnc on arm

On 16 March 2016 at 15:35, Yanjun Luo wrote: > Hi, > I think Raspberry Pi Module 3 is a good choice, I'll try it when I get a > board soon The problem with the Pi is that the obvious choice for IO, Ethernet, is connected via the USB bus. -- atp "A motorcycle is a bicycle

Re: [Emc-users] Stepper, ideal pulses without feedback

Nicklas, when I built a pcb drilling machine some years ago, I found constant acceleration and deceleration to top speed worked best, as for the most part trying to go instantly to the maximum speed the motors are capable of results in lost steps. You will need a bit of experimentation to

Re: [Emc-users] Linuxcnc on arm

On 16 March 2016 at 16:03, W. Martinjak wrote: > Ok, and any suggestions for the toolchain and build sequence? Probably simplest to compile on the device itself rather than get involved in the complexities of cross-compiling. -- atp "A motorcycle is a bicycle with a

Re: [Emc-users] Linuxcnc on arm

So how is that different from a non pre-emptive RTOS kernel? My understanding, and it's very superficial, is that the real time component of linux puts a scheduler in front of the basic LINUX kernel. So now the micro-stepping or DC-Servo/encoder support can get predictable low latency response

Re: [Emc-users] Stepper, ideal pulses without feedback

You are welcome to look at my Electronic Lead Screw Code. Follow the link to the code. It's written for a PIC in C. John "ELS! Nothing else works as well for your Lathe" Automation Artisans Inc. http://www.autoartisans.com/ELS/ Ph. 1 250 544 4950 > -Original Message- > From:

Re: [Emc-users] Linuxcnc on arm

On 16 March 2016 at 16:24, John Dammeyer wrote: > Why is it that the real time kernel hasn't become a basic part of Linux so > that the orphan Linux is the one without the kernel? With PREEMPT-RT it pretty much is. As for why RTAI wasn't ever just built-in, I am not

Re: [Emc-users] Linuxcnc on arm

So what makes the real time Linux like machine kit or for a regular PC. If drivers can muck things up. Sent from John's iPhone 4S On 2016-03-16, at 2:05 PM, bari wrote: > > That's why we'd need the kernel police to enforce the rules, if there > were kernel rules that

Re: [Emc-users] Stepper, ideal pulses without feedback

> > I have seen and run machinekit, it is linuxcnc. I have also read about > > BeagleBone. There are plenty of devices suitable to generate the > > pulses but at which rate should pulses generated? Constant > > acceleration between different speeds? > > Ideally, the accel (and decel) should be

Re: [Emc-users] Rewire Question?

Todd, I always think about the next person who has to look at my wiring. Doing this would confuse the hell out of me if I came upon it. I might even send unkind thoughts toward the last person and then fix the wires to be right. Why not pull back and reroute some of the single phase wires to

Re: [Emc-users] Stepper, ideal pulses without feedback

> On Friday 18 March 2016 16:00:27 Nicklas Karlsson wrote: > > > I have seen and run machinekit, it is linuxcnc. I have also read about > > BeagleBone. There are plenty of devices suitable to generate the > > pulses but at which rate should pulses generated? Constant > > acceleration between

Re: [Emc-users] Linuxcnc on arm

Original Message- > From: W. Martinjak [mailto:mats...@play-pla.net] > > The problem is different. > RT means looking around and fulfill all tasks in a defined timeslot. > Performance means in most cases move data as fast as you can. > And in some cases it's mutually exclusive. So what

Re: [Emc-users] Stepper, ideal pulses without feedback

You might look at the Replicape and a BeagleBone Black. There are several other capes including one with a standard DB-25 parallel port that run LinuxCNC on the Beagle. Search for MachineKit. John > -Original Message- > From: Nicklas Karlsson [mailto:nicklas.karlsso...@gmail.com] >

Re: [Emc-users] Linuxcnc on arm

On 2016-03-16 16:28, Sebastian Kuzminsky wrote: > We build and test on arm, but we currently don't produce debian packages. > > LinuxCNC 2.7 and newer work on Wheezy on armhf, you just have to build > it yourself: > > http://buildbot.linuxcnc.org/buildbot/builders/1405.rip-wheezy-armhf > > Ok,

Re: [Emc-users] Linuxcnc on arm

Maybe they just need to read about real time scheduling to assign an approriate priority or do the execution in a thread with appropriate priority. If there is a receive buffer execution should be triggered no later than half full and must be emptied before it may be filled. With time known to

Re: [Emc-users] Stepper, ideal pulses without feedback

Hi Nicklas, it should be fine to keep the step rate (velocity) constant between updates from the trajectory planner, assuming that it runs at something like 1kHz and the machine is not highly dynamic. Limiting velocity and acceleration in the step generator should generally not hurt and avoids