LinuxCNC on Raspberry Pi 5

Ouch.

forums.raspberrypi.com/viewtopic.php?t=360924

Hmm, wasn't a bad guess. Doing it at the kernel level as I suggested should be more stable. Please try and report back

The link was broken, so here it is again.

www.juniper.net/documentation/us/en/soft...s-interface-eee.html

EEE is a problem for low-latency, reliable networking, but it seems odd that it'd *ever* be on for Ethercat hardware. It's supposed to be negotiated between devices as part of the autonegotiation process (along with duplex, flow control, and so forth), and I'd be really surprised if many Ethercat devices used hardware that was able to negotiate for EEE.

What does `ethtool --show-eee <device>` show, where <device> is your Ethercat Ethernet interface?

I don't have a RPi 5 handy, but running against a PC with a Realtec RTL8125 connected to an EK1100, I see:

Interestingly, I see more or less the same thing on the port connected to a Unifi switch.  No EEE there, either.  FWIW, RPi 4s look pretty much identical here.  And the one device that I have handy that is connected to a switch that *can* support EEE apparently has EEE support entirely disabled in the driver.

If you *do* see EEE problems with Ethercat hardware, consider throwing a Beckhoff EK1100 or similar in front of your device, maybe?  EEE is negotiated on a per-link basis, and even if you have a device that (somehow) wants to negotiate EEE, then throwing a non-EEE device in the middle should disable it entirely unless it's *really* broken.

FWIW, here is another page discussing EEE (energy efficient ethernet).

askubuntu.com/questions/1411536/how-do-i...-on-my-ethernet-card

Ok, bit of a learning curve here... so EtherCat is a protocol over an ethernet physical layer designed for cycle times; ≤ 100 μs with low communication jitter for precise synchronization purposes; ≤ 1 μs.

en.wikipedia.org/wiki/EtherCAT

I'm presuming that Mesa cards use this?

So you are saying that due to this protocol, it is unlikely that EEE would be negotiated, as that would assume the Mesa card supported EEE. The implication therefore would be that the RPi 5 would NOT be using EEE since it would not be negotiated during initial configuration?

ethtool is not installed on the Pi image (0.29.2 IIRC) but I installed it using sudo apt-get install ethtool. However, it won't run...

First, the OS cannot find it (whereis says /usr/sbin) and second, executing ./ethtool --show-eee eth0 results in "netlink error: Operation not supported".

Someone said that ethtool has been deprecated and to use nmcli however I'm not sure if it is possible to access EEE data using nmcli.