Hola, después de mucho tiempo. Finalmente he armado esa pc, bien antigua, hoy con 1024 megas de ram ddr, su procesador 32 bits, y por fin su ssd. Descargué el Ubuntu propuesto, lo instale, re bien, sin internet, pero cuando probé su latencia, dió unos valores altísimos , probé, probé y luego volví a instalarle Linuxcnc 2.7.14, pero al realizar su latencia, iguaklmente muy alto los valores, por ende no me sirve para utilizarlo. Sería tan amable de compartirme su hardware tiene en su Ubuntu usado por años, sin problemas?, sigo insistiendo que me tiene que servir ñeste viejo cpu, pero los valores no acompañan para nada. Muchisimas Gracias!...

How to install 7.x to debian 13 from backports repo ?

Quick Note: Everyone in the EU, looks like the USPS is charging me for prepaid Duties, Taxes, and Fees now on top of the postage.

Upside: Duties and Taxes will be prepaid.
Downside: I have to include that cost in the Shipping quote.

If you have a local dealer, please check with them first. Even used, International sipping and duties/taxes may make my listings cost prohibitive.

Mesa 7I95T has been SOLD, the rest is still available.

Beckhoff EL5001-0012

I think the issue is that you are not using the feedback from the same encoder that's generating
the index. In this case, homing to index cannot work.

I'm certainly open to being educated here but I was reasonably convinced by what I was seeing. Have a look at my notes and perhaps you can see where / if I may have misunderstood what was happening:
www.murraye.com/2026/08/improving-homing...acy-on-linuxcnc.html

In my case, with 5um resolution scales and closed loop controls, my final resting position after homing can't be any more accurate than the resolution of the scales allow, so perhaps I've been chasing up a dead end anyway? A positional accuracy of 5 or 10um from true is probably the best I could hope for on a good day.

The PID element was initially due to my controllers being unstable but the homing velocity did seem to impact accuracy too.

Many thanks for your response.

I have found that 7.x kernels are better than 6.s kernels jitter wise.

It sounds like you are not using the index hardware at all.
There should be no effect of LinuxCNC timing or PID tuning
on the index position homing precision, if the index hardware is
actually used.

That is, the precision of position capture at the index position is
independent of the motion accuracy, though of course motion accuracy
after the index position is captured _is_ dependent on PID etc.

Hello everyone,
I am looking for available options to read and process a lathe spindle encoder over EtherCAT. For context, the spindle setup consists of an induction motor and a VFD controlled via RS485 or 0-10V.
Here is what I am currently considering:
• Beckhoff encoder modules.
• Mesa cards or other FPGAs. However, I would prefer a pure EtherCAT solution.
• CATIO-A IO board. It is not entirely clear to me whether it can fully support and handle a lathe spindle encoder.
• EtherCAT development boards. Are there any ready-made firmware options available for this specific task?
• Any other options?
I would appreciate any advice, experience, or recommendations you can share!


 

i have upgraded to trixie 6.12.113 kernel and jitter now is much worse..
Any updated instructions for improving jitter?
I think every kernel update make things worse.

For reference, here are some results showing a comparison between the original proximity switch homing and the "index gated" implementation.
 
The "optimisation" process produced the biggest improvements which were the result of finessing the PID values and slightly reducing the homing speed to minimise the delay between reading the index pulse and processing the data. Both methods were significantly improved this way but the end results were almost identical.
For the test setup, I repeatedly homed the machine (typically 20 times, as shown), with the absolute position automatically logged and plotted.