What's the PC Spec for Mesa 7i76e ?

Hello,

I'm in the process of converting my lathe to cnc, finished the mechanical changes and now comes the software.
I'm using stepper motors and an ABZ encoder with 360ppr for spindle.
I saw that Mesa 7i76e connects through ethernet and seems to have all that 7I76-5I25 PLUG-N-GO KIT has
I have already wasted some money on some windows based solutions, so before I order the board I would like to know if there are any special conditions my pc has to meet in order to have this board working at it max potential.
Does the latency matters if I'm using an external board?
Right now I'm using a desktop pc, but with this ethernet board in the future I might use a laptop. Do you guys think a laptop configuration would work with this board?

Latency does still matter, but the latency requirement is much less than that required for software stepping.
A laptop can work, but I wouldn't recommend it, and most aren't capable of good enough latency.

This is a latency histogram from an older pentium laptop runnung linuxcnc2.7.7 with UBUNTU 10.04
Latency is pretty good.



I want to use that one for my mill with a 7i76e and I am pretty sure not getting problems.

Norbert

Remember with an Ethernet Mesa card you have to use a Preempt-RT kernal rather than RTAI. An older single core processor like that might not have enough horsepower to run a Preempt-RT kernel well, and a laptop with all of its power-saving features disabled may run dangerously hot.

Hallo Tod,

you are so right, here the same Laptop with Wheesy and RT_PREEMP Kernel,
Not very good



Norbert

You may want to try again, your histogram image, does not show that the preemp-rt kernel is the one running.

Laptops can have decent latency with Preempt-RT (dell E2420):

freeby.mesanet.com/e6420.png

Note that you cannot change from line to battery power or change backlight brighness on that particular
laptop without having huge latency spikes, that said, I have run real time Ethernet cards on that laptop
for days on line power without issue