Raspberry Pi 4 Tutorial - fatal error

Find older packages and use them. There are no older packages for RPi 4, but the packages for RPI 3 work. Get those for raspbian 9 and it should all work again.

I'm back on a decent computer and could look for it. Here is how I solved the python-rsvg missing package
forum.linuxcnc.org/18-computer/36879-ras...pi-4?start=50#140800

I assume that other old packages can be found at the same place.

I gave it a whirl and one thing that got me a little off-track was that I had gotten used to cutting and pasting the commands and it was late evening and when I got to this one "sudo apt install openbox, lxterminal and lightdm" it failed because I should have entered:

sudo apt install openbox
sudo apt install lxterminal
sudo apt install lightdm

I also lost my network connection (my fault) while debuild -uc -us was running and had to start it again.

Now, how do I start Linuxcnc from the command line? It is not on the Caja menus and I tried "linuxcnc" and I get "command not found". At this point I was just going to check latency as I don't have 7i76E yet.

I tried linuxcnc at the command line but got "command not found".

I'm going to try what Andy said and see what happens. I'm going to get a couple more SD cards so I can run through it again without wiping out this one.

Thanks

Yes, I did. But I just did everything on the Install LinuxCNC
page again and it is now working. I must admit that every time I read about someone wanting to use a RPi my thoughts when to "Do you want to build a CNC machine or play with a Pi?" I must say that so far I am impressed with how snappy LinuxCNC feels and how bright the display looks. I have a Pi 4 with 4mb. Now to run the latency test and see how that goes.

Thanks
John

I ran the latency test with 6 glxgears running but no other abuse.
Servo thread (1ms): 73079
Base thread (25us): 93953

If I run just the servo thread the number goes up over 100,000.

Anything I should try to lower the latency on the Pi4?

I may get a 7i76E and give this a try. Right now I'm using a 6i25+7i76+7i83

John

You could also use your 7I76 and 7I83 with a 7I92H or 7I92M replacing the 6I25