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Start linuxcnc from the command line, read the error about the missing pin. It probably tells you the line number. Comment it out until Linuxcnc starts and review halshow to get the right spelling/pin name. This is just basic trouble shooting, not ethercat related.

linuxcnc -l 

is a very handy command (Lower case -L)

Yes, I was suggesting a totally new stepper driven Z axis/lifter assembly.

A few of us did  a lot with plasma before Plasmac burst onto the scene.

Generally, we used a touch off subroutine that was called before the M3. JohnT has a good starting example here (and some other resources)
gnipsel.com/shop/plasma/plasma.xhtml  I think I modified this to probe away until loss of contact before saving the torch height.

Cornerlock just needs to monitor the current velocity and disable the THC if it falls below a threshold (say 90%) of the feedrate. This used to be  a problem becasue Linuxcnc never saved the feedrate,   but a kind developer heard our cries and its now published in motion as motion.feed-upm and a few other variations. Here though your THC will need some kind of input that disables it.
linuxcnc.org/docs/stable/html/man/man9/m...9.html#MOTION%20PINS

I have attached a working cornerlock component

The build system should just build what you have changed.

Probably start with qtdragon and customise it to suit. TTS toolng and a probe works well in it. I use it. If you premeasure tool length as Tormach does it, you don't need a tool height sensor.

Ethercat is certainly a lot easier to use today than it used to be but becasue you are interfacing linuxcnc with the ethercat master, there is some additional complexity in setting it up. But it only took  a day for me to get movement.

AndyDM01 wrote:

I would be very happy if someone could point me to a list of standard net to build stuff from ...
like : net x-home or net x-limit or net torch-on .... stuff like this 
OR I don't have to care and i can just create whatever i want?
I want to use most of the IO on my card that has 16 inputs and 16 outputs ... 
before i had a usb-bob for mach3 and had 4 inputs and 4 outputs

 

I think that is the biggest difference between Linuxcnc and Mach3,  Here, you start with a blank canvas, Mach has some structure about its setup.
Linuxcnc does not care and you can use whatever you want.
Over time you will build your own style that works for you. 
With ethercat, I like to put the drives at the top of the list so they get numbered the same as th ejoints but you can set a name j0.j1 etc.

The required PID rate also depends on what you are controlling.
 If you are controlling torque, you need a higher PID rate
than if you are controlling velocity (with the drive controlling the
lower level, higher frequency loops)

A typical position mode servo drive may have 3 nested PID (or similar)
loops, from fastest to slowest:

torque command to PWM out
velocity command to torque out
position command to velocity out

 

"did read almost half of the linuxcnc documentation"

That's the issue.

It's there you just need to look.

conv_bit_float will just turn a bit to 0.0 or 1.0

Normally  the way jog increments are selected are with a mux
component, say mux4

man mux4
 

Thank you. Without your incredible help, I would still be searching for how to implement this project. My current CNC machine is a 5axismaker with Mach4 software and Pokeys57U hardware. After reaching out to the vendor, they confirmed it can be converted to run LinuxCNC and suggested I follow this post: forum.linuxcnc.org/24-hal-components/29816-pokeys-ethernet. My first step will be converting the machine to LinuxCNC as well as figuring out LinuxCNC. Then, I'll create a custom HAL to apply external offsets to the original g-code using data from the camera using OpenCV. I feel like I've done adequate research beforehand but the actual implementation is where I will see how difficult this gets. While I'm not as experienced with CNC control, I'm more comfortable with programming but we will see. Hopefully, I can show the completed project as soon as possible  !

I have external push buttons for jog increment and I'm trying for example to update halui.axis.x.increment with the value 0.001
conv_bit_float seems like it should work for this?

It's not obvious how I get the float value of 0.001, assigned to the float value?
Error is postgui.hal:202: Pin '0.001' does not exist

The external button is updating net jog-inc-1 when I push the button (observed in Hal show)
Excerpt from postgui is as follows:

loadrt conv_bit_float count=1
addf conv-bit-float.0 servo-thread

net jog-inc-1 <= arduino.keypad.Jog-Inc-1
net jog-inc-1 => conv-bit-float.0.in
net jog-inc-1f  conv-bit-float.0.out 0.001

You lose bandwidth by going to a lower servo PID rate. If that doesn't
matter because the system you're controlling is slow, there is no price
in going for a lower control speed.

With a sampling rate of 250Hz, you can actually measure up to 125Hz. In reality
the limit is usually between 1/5 and 1/3 that frequency before difference between
a sampled and a time continuous system become apparent.

So with 250Hz you're approximately limited to 50Hz of control
bandwidth. To me that seems terribly low. On my own lathe I have a
resonance at approximately 300Hz. Since I have the servo thread running
at 4500Hz (because that's the maximum rate the encoders I use support)
I was able to eliminate that resonance.

On the other hand, what do you lose when going for a higher sampling
rate? The only thing I can come up with is processor time, but that
seems hardly an issue on a modern PC. And I'm doing this on an RT_PREEMPT
kernel, so it's not even Xenomai or RTAI.

I got the smallest Gravograph machine (UNICA) up and running.
Thanks once again for your input and this amazing forum in general

Now, the larger machines have 1-phase AC motors and a separate speed control PCB that's actually a single-phase frequency converter. So far so good, there's also an encoder and a potentiometer to set speed, BUT:
The potentiometer is 500 kOhm and voltage across the potentiometer is merely 0,22 V.

Is there any way to get this to work with LinuxCNC?

[EDIT]
I'd like to apologize for crashing Hans Peter - HPWs thread.
Would it be better to move my issues to a new topic instead?

Hans Peter, verzeih mir bitte, dass ich mich hier hineingedrängt habe

looks like golang did it. Thanks a lot Scott!!

In fact, it is that exact work that has got me started. A great starting point to build from.

Hi folks,

I'd like to create a new interface and am in need of some help. I'd like to create something like the attached mockup, and overall it is fairly ambitious. I've installed and messed around a bit with LinuxCNC, a few existing interfaces, and Qt Designer, but haven't been able to completely figure it out. I have some programming experience in C# but not in Linux. Trying to sort out all the pieces of LinuxCNC is not easy, so I'd be happy to pay for someone's time to help get me started with a bit of tutoring or coding work. Once I get started off right I should be able to take it from there.

The end goal is to create a modern looking and user-friendly interface, with a lot of common sense features built in. I am a mechanical engineer and own a small machine shop, and I've got some designs for a CNC machine I'd like to build and possibly sell. If we can create an interface that is also customizable and open source so others can make use of it, that would be a bonus. I would like to avoid any dependencies on existing interfaces, not sure how reasonable that is but I know it will definitely be much more work.

I would like to use EtherCAT and have seen some posts regarding it, but not sure how well it is supported, or if there are any issues with implementing it. The system ideally would be a small PC connected directly to EtherCAT servos drives, I/O modules, etc.

The interface design is based on  www.openbridge.no/.

Any advice, cautions, referrals, etc. would be greatly appreciated!