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W4 is not used on the 7I84U, its position does not matter.
(note that the 7I84U was tested with the as shipped jumper settings)

What LEDs are illuminated on the 7I84U when the system is powered
(but linuxCNC not running?)

You should have 2 yellow LEDs and 1 red LED illuminated. If not, 
there is a power issue.

Do you have both FIELDA and FIELDB voltages applied? 

 

I just noticed that halui.axis.x.pos-relative read the value correctly and it retains it after restart. The axis.x.pos-cmd always starts at -496.2247. When i move the robot the halui.axis.x.pos-relative reports the correct absolute position but the robot moves as if it has been started at -496.2247. Any ideas?

Hi, I have a delta robot built on ethercat and running linuxcnc.
We recently got drives with absolute encoders so i had to make a specific homing procedure that just triggers the internal homing on the drives.
The drives then reset their encoder positions internally to 0 or home offset if it's set in HAL with lcec.
Then, when using the robot i could move it somewhere, turn off linux cnc and then start it again and linuxcnc always shows the same position when starting [ 0. , 0. , -496.22474747]. When i disable the home offset this number still stays the same. I move the robot to [0,0,-700], restart and it still shows the same position, and then moves "ignoring" the soft limits. The encoders themselves retain their position information properly, it's just linuxcnc that reads it wrong (or doesn't read it for some reason) What am i missing here?
Here are the files for my config.

vibaration at 40krpm

 

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He comprobado por si había cortocircuito y no encontré ningunoLa tierra la tengo conectada de todos los cables blindados en una sola punta dentro de la caja de control en una barra de tierra que a su vez esta conectada a la tierra de la redEl problema fue cuando conectar el thcad2 antes de conectarlo, estuve cortando y todo funcionaba bien también es verdad que lo conecta y no lo configuré en linuxcnc por el hecho, que no encontráis la pantalla de thcad2 en pncconf y no se como configurarlo en .hal y solamente le di hacer una prueba arrancando la antorcha y ya los motores no se movían al instante.

ya pedí los chips pero me gustaría encontrar lo que a producido el fallo antes de que me pase lo mismo. Podrías ayudarme. Gracias de nuevo

Thanks for the link.
Looking at locale.

LC 2.9.2:
Menu-config has an extra step for setting locale.
When en_AU is selected, a pop-up shows C.UTF and en_AU.UTF, adds a warning about setting locale, then Ok to accept en_Au.
Then locales are generated before returning to the menu-config dialog.

LC 2.9.4
The extra step is not present.
The return to the dialog is too quick to see if a locale is generated.

Research on Debian locale seems to require editing of files.
I will start reviewing this tomorrow (and re-read the reference link).

John

Thank you for your pointers in the right direction. Helps a lot.

Unfortunately the 7i84 still does not report back. I just discovered that jumper w4 needs to be removed, even though it's not mentioned anywhere. I've been running a simple half file and use your suggested mesaflash prompt to check available serial devices. Is there something else I can do?

loadrt hostmot2
loadrt hm2_pci config=sserial_port_0=000xxxxx

loadrt threads name1=servo-thread period=1000000

addf hm2_5i25.0.read servo-thread
addf hm2_5i25.0.write servo-thread
addf hm2_5i25.0.pet_watchdog servo-thread

start

For axample:
Aluminium extrusion profile L=1200mm (2.9 kg) vs aluminium 50x50x2 tube L=1200mm (3.6kg)

I must say that the weight comparison seems very counter intuitive.

[edit]

you are comparing aluminium extrusion profile to  50x50x2 steel tubing (8000kg/m3).

The most likely problem is that you have 'anglejog.current-scale' = '0'.

Note that the 'anglejog.scale-in' value is only sampled when 'anglejog.enable-in' is false. (See 'Notes' in the man page linked above)

You may want to have a look at the anglejog sim config :
configs/sim/axis/anglejog

 

Thanks, well spotted! I was hoping that 1/3200 microstepping would work.
Perhaps I will have to do a 1/3 reduction later. For now I think I'll try how this works.

The goal is to get linuxcnc up and running first and try to configure everything properly



The point of the 80x40 extrusion profile I certainly do not agree with as a mechanical engineer.
The 80/40 extrusion profile has a much higher stiffness compared to a normal tube. Especially compared to an aluminum tube.

For axample:
Aluminium extrusion profile L=1200mm (2.9 kg) vs aluminium 50x50x2 tube L=1200mm (3.6kg)

Comparison of Bending Resistance
ProfileDirection (axis)                                        Section Modulus (W) 

80x40 extrusion
Major axis (80 mm high) → bending about        X = 8,898,884 mm³ 
Minor axis (40 mm high) → bending about        Y = 120,303 mm³

50x50x2 mm box
Any axis (symmetric) → c = 25 mm                    X and Y = 5,912 mm³

Key Differences:

In the x-axis, the 80x40 profile has ~1500× higher section modulus (1500x stronger!) and is 20% less heavy than the 50x50x2 box.

In the y-axis, it still has ~20× higher section modulus (20x stronger!).

Agreed on the gear reduction or machining a smaller pulley. I think they make htd in 3mm pitch so you can reduce pulley size.

The goal with plasma is to accelerate as fast as possible to the desired cutting speed to minimize slag...... That's basically the entire goal..... The less time you are in-between stopping and cut speed the less slag you will have. So keep all motion components as light and strong as possible. That 80/20 t slot extrusion is heavy and weak (for the weight), use square tube instead.

Also 3d printed parts are fine for a prototype/hobby machine but you are building a machine that shoots sparks everywhere and makes things very hot. Plan for machining the parts out of AL if you want to use it in an industrial environment.

Hope that helps

A guess:

setp hal_gpio.pin-40-out-invert true

Running LinuxCNC and then running:

halcmd show all | grep invert

in a terminal window should give the the exact naming syntax

 

1 No double posting
2 most VFD's can do 0-5V or 0-10V settable, see manual
3 to invert pins on LinuxCNC it is as simple as :Should be similar for RPI, but i do not use RPI so no way of confirming from my side, give it a try.

Hello everyone,

I'm setting up a PWM-controlled spindle for my LinuxCNC machine. My analog DC motor controller requires a 0-10V input, which I'm generating with this specific PWM-to-analog converter: www.amazon.co.uk/Digital-Analog-Module-C...&smid=A2BXCFIGGD7VDT.

The PWM signal is sourced directly from a Raspberry Pi 5's GPIO, routed through our custom-designed isolator board HAT, V1.1, which you can find details about here: github.com/data124001/Isolation/wiki. We're running LinuxCNC version 2.9.1 and using the hal_gpio library.

The core issue is that this specific PWM-to-analog converter appears to invert the control signal: a 100% PWM duty cycle from the Pi (and hal_gpio) results in zero motor speed, while a 0% PWM duty cycle results in full motor speed. This means my spindle speed control is completely reversed from what's expected (higher LinuxCNC speed command = lower motor RPM).

We have confirmed that the PWM signal generated by the Raspberry Pi 5's GPIO (whether directly or via our custom isolator board) is behaving correctly in terms of duty cycle interpretation (e.g., 50% duty cycle is "half on"). However, without this specific PWM-to-analog converter in the loop, we have no meaningful 0-10V speed control for the motor controller, only basic on/off, as the raw PWM is unsuitable.

Therefore, the problem lies squarely with the inversion introduced by the Amazon PWM-to-analog converter itself when converting the standard Pi PWM.

My question is: What are the most effective and robust methods within LinuxCNC's HAL configuration to invert the hal_gpio PWM signal before it reaches this converter? I'm looking for a HAL-based software solution to achieve the correct 0-10V spindle speed control (where a higher LinuxCNC spindle.0.speed-out value corresponds to a higher analog voltage to the motor controller and thus higher motor RPM).

I will be attaching my HAL and INI files to this post to provide full context of my current setup.

Any specific HAL configurations or example code would be incredibly helpful!

Thanks in advance.