Help selecting new PC to run Mesa 7I92 Ethernet

PCW wrote:

OK so you have a intel MAC, this means you will need to disable a Ethernet driver feature called "IRQ coalescing" if you have not already. This is described in hm2_eth man page

You can do this temporarily (till the next reboot) with the command:

sudo ethtool -C [your_ethernet_device_name] rx-usecs 0

Where [your_ethernet_device] is eth0,enp0s25 or similar
You can determine the Ethernet device with the command:
ip a

You can check if this works by checking the 7i92 ping times before and
after you run the above ethtool command

Can you post a halscope plot image of the problem you see?
From your description, it does not seem servo thread or PC timing related

hardware−irq−coalesce−rx−usecs 0

pl7i92 wrote:

you can also do this in the interfaces
sudo gedit /etc/network/interfaces

#7i92 2019
auto eth0
iface eth0 inet static
address 192.168.1.4
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.1
dns-nameservers 8.8.8.8 4.4.4.4
hardware-irq-coalesce-rx-usecs 0


then
sudo /etc/init.d/networking restart
if it fails
sudo /etc/init.d/networking stop
sudo /etc/init.d/networking start

ofcause as you got the 7i92 jumperd
if yoiu use other networking adresses just correct it

tommylight wrote:

Thank you very much.
I do not need it personally , I just felt bad that I could not help the user who needed it since I never retrofitted such machine. I have done plenty of other machines.

tommylight wrote:

If that line moves after a while on it's own, that is a sign that drives are getting hot ( very rarely ) or motors have issues with brushes, so you should open the back of the motor only to where you can we the brushes and use compressed air to clean them. That will fix the moving f-error line for sure.

PCW wrote:

Well, that's fairly terrible latency (I see a 370 usec there and there may be worse)

Do you have all power management turned off?

If Intel AMT is an option in the BIOS, it should be turned off also

Heres a DC7800:

peter@dc7800:~/linuxcnc/configs$ ping 10.10.10.10
PING 10.10.10.10 (10.10.10.10) 56(84) bytes of data.
64 bytes from 10.10.10.10: icmp_seq=1 ttl=64 time=0.130 ms
64 bytes from 10.10.10.10: icmp_seq=2 ttl=64 time=0.080 ms
64 bytes from 10.10.10.10: icmp_seq=3 ttl=64 time=0.080 ms
64 bytes from 10.10.10.10: icmp_seq=4 ttl=64 time=0.080 ms
64 bytes from 10.10.10.10: icmp_seq=5 ttl=64 time=0.084 ms
64 bytes from 10.10.10.10: icmp_seq=6 ttl=64 time=0.084 ms
64 bytes from 10.10.10.10: icmp_seq=7 ttl=64 time=0.090 ms
64 bytes from 10.10.10.10: icmp_seq=8 ttl=64 time=0.081 ms
64 bytes from 10.10.10.10: icmp_seq=9 ttl=64 time=0.081 ms
64 bytes from 10.10.10.10: icmp_seq=10 ttl=64 time=0.081 ms
64 bytes from 10.10.10.10: icmp_seq=11 ttl=64 time=0.080 ms

(the first ping is longer because the host needs to do an "ARP who has 10.10.10.10" before the actual data transfer)