LinuxCNC on Raspberry Pi 5

The good news is that the RPi and Mesa 7i96s are communicating and appeared to be doing so reliably using the Dragon GUI until a string of these messages appeared:

hm2/hm2_7i92.0: error queuing read! iter=xxx
hm2/hm2_7i92.0: error finishing write! iter=xxx

If I run the following, there appears to be dropped packets:

sudo chrt 99 ping -i .001 -q 10.10.10.10  /* forum.linuxcnc.org/27-driver-boards/4837...rite?start=20#266420 */

About 25% were dropped when using a 30 cm CAT cable (not sure what type, shown in photo above). Changing to a longer CAT 5e cable resulted in a tiny percentage of dropped packets. Nevertheless, the errors keep appearing when running Dragon GUI -- I'm not suggesting that Dragon GUI is the issue here.

Its a hardware issue. please read my tutorial here
docs.google.com/document/d/1jeV_4VKzVmOI...diY/edit?usp=sharing

Thanks, I will give that a try tomorrow and report back.

Hey Richie, how did you go with the RPi 5? I have the same + Mesa 7i96s in Blenheim…

Running this on RPi 5 8 GB with Mesa 7i96s:

latency-histogram --nobase --sbinsize 1000

With essentially no load on the Pi, have after about 400 seconds:

min (us) = -18.8
max (us) = 19.2
sdev (us) = 0.9

With 1x Glxgears, after about 80 seconds:

min (us) = -16.6
max (us) = 14.5
sdev (us) = 0.9

With 2x Glxgears, after about 80 seconds:

min (us) = -20.4
max (us) = 15.2
sdev (us) = 1.6

With 3x Glxgears, after about 80 seconds:

min (us) = -18.6
max (us) = 16.5
sdev (us) = 2.2

With 4x Glxgears, after about 80 seconds:

min (us) = -17.2
max (us) = 18.3
sdev (us) = 2.6

With 5x Glxgears, after about 80 seconds:

min (us) = -21.6
max (us) = 20.6
sdev (us) = 3.0

With 6x Glxgears, after about 80 seconds:

min (us) = -16.5
max (us) = 18.1
sdev (us) = 3.1

With 10x Glxgears, after about 80 seconds:

min (us) = -23.8
max (us) = 16.6
sdev (us) = 3.5

Seems that the 7i96s ethernet connection to the Pi has died again during these tests.

======================

Repeating the 10 gears version on HP i5 8100 Elite SFF x86_64 6.1.0-13-rt-amd64 2.9.1 3.6 GHz

With 10x Glxgears, after about 200 seconds:

(1000 us servo thread)
min (us) = -80.8
max (us) = 79.3
sdev (us) = 1.5

(25 us base thread)
min (us) = -24.9
max (us) = 42.4
sdev (us) = 0.8
 

Being new hardware, its possible you are a victim of enegy efficient ethernet.

ref:  www.juniper.net/documentation/us/en/soft...e%20link%20is%20idle .

Could you try disbale it by adding
igb.EEE=0

to your boot parameters (where you put isolcpus) I think its boot.txt on the pi
I have no idea if this will work!