Raspberry PI4, VLAN and 7i76E for XYYZ Gantry router

Hello all,

Finally done with replacing/upgrading my prototype gantry router from wooden parts to full steel parts, ready to power on the old (Dell Optiplex 760) PC and making the first moves again and than it happens...
BIOS Battery dead, no way to make it boot again (replaced battery, but keeps hanging in the bios, even after resetting,...)

So I need a new PC-setup, and mayby it's time to switch over to the mesa-cards and throw the parport-BOB away.

Currently I'm thinking of the following:

• Raspberry PI 4B (v1.2 4Gb)
• Mesa 7i76E

In my opinion, WiFi is only good for mobile devices so I would like to connect the RaspPi to a wired network cable.
As the raspPi has only one NIC, and I need 2 networks (Home network and Machine-Mesa network) I was thinking about using VLAN's.
I have some spare VLAN capable switches over here.

Will it be a good idea to use VLAN's ?
Or better to invest in an extra RJ45-over-USB for the home-network ? (As I understand the built-in WLAN adds some extra latency)

The Home network will be used to transfer files to the machine, general work and mayby VNC if latency allows it.

Also, is the raspberry PI4 allready adviced for new builds ? Any (budget friendly) alternatives that are adviced ? (I have a spare PI 3B)
I don't expect high-level, I'm using my machine for hobby-project and for learning myself new things.

Thanks !

General specs of my CNC:

• Gantry (XYYZ)
• Area (xyz) +/- 1300x800x280mm
• Stepper Motors
• 4x Leadshine DM556S
• Makita Router (RC701)
• Far Future: Rotary Axis
• Far Future: (Chinese) Spindle with VFD

NO
vlan is in reality nothing more than adding a bit more info into the tcp messages. Plus you need additional decisions in every device that regards the vlan tag. VLAN has its use, but is often missunderstood.

Use a direct cable between rpi's ethernet hw port and mesa. Give it unique address range. Use the wifi to connect to the rest of the world.
Mike

You _can_ run a Mesa Ethernet card through a switch, as a matter of fact
this allows you to run multiple Mesa Ethernet FPGA cards from one host
Ethernet port, however

1. This does add store-forward latency to every packet so best for faster host machines
2. The current hm2_eth driver does not allow shared use of the host Ethernet interface
3. Its probably much easier to just use WIFI or a USB-Ethernet dongle

Thanks,
That is a clear answer, I will try the interal WiFi first.

In the mean time I received my PI4, and installing linuxCNC at the moment.

So hopefully by the end of next week I have again a running linuxCNC (still waiting for the Mesa-board and need to build a new electrical cabinet)

Did you install 2.8 deb or buster or some dev. version of 2.9 then add the RT kernel update

I followed the descriptions found on gnipsel.com (thanks JT !!! ) and arround the linuxCNC pages/forum

Currently I still need to figure out the following (the text in red)
forum.linuxcnc.org/27-driver-boards/3559...ethernet-mesa-boards
Need to find out how to get the some using CLI as network-manager isn't installed yet.

So I did the following (in this order)

1. Install PREEMPT/Raspian/LinuxCNC/...
gnipsel.com/linuxcnc/uspace/rpi4-rt.html (all the Raspberry Pi 4 pages, takes a while...)

2. Some small extra's
3. Install 7i76e tool
gnipsel.com/linuxcnc/7i96/index.html (installing only)

4. Install Mesaflash
I'm able to open LinuxCNC (command linuxcnc)
The uname -a returns the following:
I used the 2.8 branch, linuxCNC returns 2.8.0~pre1
After building linuxCNC I got (and installed) a deb-package with the nameCurrently I'm waiting for my mesa-card to arrive before continuing...

Before you settle on the Raspberry, have a look at the Odroid H2+
It has twin NIC and a Celeron CPU. I've only done a brief latency test but its better than my J1900 using Tommy's Mint 19.3 install.
The 2 Gb NIC though needs a driver installed as its very new. I just followed the link on the Odroid wiki and placed the driver on a USB stick and it was real simple from there.

In my experience a lot of Wifi issues are due to crappy WAP on home grade router. Now I've upgraded to a enterprise grade Dlink DSR500 router I find wifi to my machine much more reliable.