Raspberry Pi 4 & MESA 7i92

The SPI errors are expected with a long cable.
You can set the SPI clock frequencies in the driver command line
(man hm2_rpspi)


"Note: Using POSIX non-realtime"

This means you are not running a real time kernel so you need to install a real time kernel on your RPI before LinuxCNC will run reliably

Thanks PCW!

The SPI errors are expected with a long cable.
You can set the SPI clock frequencies in the driver command line
(man hm2_rpspi)

Ok. Now I try to lower the spi clock. But then I'll do what you suggest

"Note: Using POSIX non-realtime"

I have already installed the rt-kernel.
I think this note was referred to a non-realtime module running (may be display/keyboard devices, I don't know).
I didn't realize that linuxcnc was not using real-time by issuing this message.

How could I check if the linuxcnc is using all the real-time capabilities?

Thanks!

You can check if you really have a real time kernel installed with

uname -a

Thanks PCW!

uname -a

Ok, I know about this command, and I check it several times as I build the rt.
I'm not with my toy right now. I'll send you my kernel version later, just in case.

Note: Using POSIX non-realtime

So, I don't know why linuxcnc send this message. That's why I ask you for another kind of check, maybe some linuxcnc tool to dig internals.

Another hint: I built linuxcnc from source (2.9 master)

Thanks a lot!

Did you build the uspace version of LinuxCNC?

The only time I have seen the "Note: Using POSIX non-realtime"
message is when I have run LinuxCNC on a non-RT kernel.

Here is what I normally get (LinuxCNC 2.9 uspace with different hardware):

peter@pcw-HP-EliteDesk-800-G1-USDT:~/linuxcnc-dev/scripts$ linuxcnc
LINUXCNC - 2.9.0~pre0
Machine configuration directory is '/home/peter/linuxcnc/configs'
Machine configuration file is '7i96masterpe.ini'
Starting LinuxCNC...
Found file(REL): ./hm2-pidstepper-master-pe.hal
Note: Using POSIX realtime
hm2: loading Mesa HostMot2 driver version 0.15
hm2_eth: loading Mesa AnyIO HostMot2 ethernet driver version 0.2
hm2_eth: 10.10.10.10: Hardware address: 00:60:1b:16:00:02
hm2_eth: discovered 7I96
hm2/hm2_7i96.0: Low Level init 0.15
hm2/hm2_7i96.0: 51 I/O Pins used:
hm2/hm2_7i96.0: IO Pin 000 (TB3-01): IOPort
hm2/hm2_7i96.0: IO Pin 001 (TB3-02): IOPort
...............

Thanks PCW!

The only time I have seen the "Note: Using POSIX non-realtime"
message is when I have run LinuxCNC on a non-RT kernel.

I had an issue with the RT, now solved

Now on the road again, I have this error:

LINUXCNC - 2.9.0~pre0
Machine configuration directory is '/home/pi/linuxcnc/configs/gmoccapy-rpi3-mesa-mill-v1.0.1'
Machine configuration file is 'gmoccapy-rpi3-mesa-mill-v1.0.1.ini'
Starting LinuxCNC...
Found file(REL): ./gmoccapy-rpi3-mesa-mill-v1.0.1.hal
Note: Using POSIX realtime
hm2: loading Mesa HostMot2 driver version 0.15
hm2_rpspi: Unknown board at SPI0/CE0: MESA7C81
hm2_rpspi: rtapi_app_main: Operation not permitted (-1)
./gmoccapy-rpi3-mesa-mill-v1.0.1.hal:30: waitpid failed /home/pi/linuxcnc/bin/rtapi_app hm2_rpspi
./gmoccapy-rpi3-mesa-mill-v1.0.1.hal:30: /home/pi/linuxcnc/bin/rtapi_app exited without becoming ready
./gmoccapy-rpi3-mesa-mill-v1.0.1.hal:30: insmod for hm2_rpspi failed, returned -1
Shutting down and cleaning up LinuxCNC...
hm2_rpspi: not loaded
<commandline>:0: exit value: 255
<commandline>:0: rmmod failed, returned -1
hm2: unloading
<commandline>:0: unloadrt failed
Note: Using POSIX realtime

I test the connectivity with the 7c81 and it is ok.

I also see this link:
forum.linuxcnc.org/18-computer/36879-raspberry-pi-4?start=170
But it seems not to be the same case, I think.

Thanks!

If the 7C81 is not recognized it means that you need o update your LinuxCNC installation to the latest. The unable to load issue might be because there are still modules loaded when you launch LinuxCNC, sometimes this takes a reboot to fix.

Here's what I get with recent 2.9 and a 7C81 on a RPI4:

LINUXCNC - 2.9.0~pre0
Machine configuration directory is '/home/pi'
Machine configuration file is '7c81-1k.ini'
Starting LinuxCNC...
emc/iotask/ioControl.cc 701: can't load tool table.
Found file(REL): ./hm2-pidstepper.hal
Note: Using POSIX realtime
hm2: loading Mesa HostMot2 driver version 0.15
hm2/hm2_7c81.0: Low Level init 0.15
hm2/hm2_7c81.0: Smart Serial Firmware Version 43
hm2/hm2_7c81.0: 57 I/O Pins used:
hm2/hm2_7c81.0: IO Pin 000 (P1-01): IOPort
hm2/hm2_7c81.0: IO Pin 001 (P1-02): PWMGen #0, pin Out0 (PWM or Up) (Output)
hm2/hm2_7c81.0: IO Pin 002 (P1-03): StepGen #0, pin Step (Output)
hm2/hm2_7c81.0: IO Pin 003 (P1-04): IOPort
hm2/hm2_7c81.0: IO Pin 004 (P1-05): StepGen #0, pin Direction (Output)
hm2/hm2_7c81.0: IO Pin 005 (P1-06): IOPort
hm2/hm2_7c81.0: IO Pin 006 (P1-07): StepGen #1, pin Step (Output)
hm2/hm2_7c81.0: IO Pin 007 (P1-08): IOPort
hm2/hm2_7c81.0: IO Pin 008 (P1-09): StepGen #1, pin Direction (Output)
hm2/hm2_7c81.0: IO Pin 009 (P1-11): StepGen #2, pin Step (Output)
hm2/hm2_7c81.0: IO Pin 010 (P1-13): StepGen #2, pin Direction (Output)
hm2/hm2_7c81.0: IO Pin 011 (P1-15): IOPort
hm2/hm2_7c81.0: IO Pin 012 (P1-17): IOPort
hm2/hm2_7c81.0: IO Pin 013 (P1-19): Encoder #0, pin A (Input)
hm2/hm2_7c81.0: IO Pin 014 (P1-21): Encoder #0, pin B (Input)
hm2/hm2_7c81.0: IO Pin 015 (P1-23): Encoder #0, pin Index (Input)
hm2/hm2_7c81.0: IO Pin 016 (P1-25): IOPort
hm2/hm2_7c81.0: IO Pin 017 (J5-TX0): IOPort
hm2/hm2_7c81.0: IO Pin 018 (J6-TX1): IOPort
hm2/hm2_7c81.0: IO Pin 019 (P2-01): IOPort
hm2/hm2_7c81.0: IO Pin 020 (P2-02): PWMGen #1, pin Out0 (PWM or Up) (Output)
hm2/hm2_7c81.0: IO Pin 021 (P2-03): IOPort
hm2/hm2_7c81.0: IO Pin 022 (P2-04): IOPort
hm2/hm2_7c81.0: IO Pin 023 (P2-05): IOPort
hm2/hm2_7c81.0: IO Pin 024 (P2-06): IOPort
hm2/hm2_7c81.0: IO Pin 025 (P2-07): IOPort
hm2/hm2_7c81.0: IO Pin 026 (P2-08): IOPort
hm2/hm2_7c81.0: IO Pin 027 (P2-09): IOPort
hm2/hm2_7c81.0: IO Pin 028 (P2-11): IOPort
hm2/hm2_7c81.0: IO Pin 029 (P2-13): IOPort
hm2/hm2_7c81.0: IO Pin 030 (P2-15): IOPort
hm2/hm2_7c81.0: IO Pin 031 (P2-17): IOPort
hm2/hm2_7c81.0: IO Pin 032 (P2-19): IOPort
hm2/hm2_7c81.0: IO Pin 033 (P2-21): IOPort
hm2/hm2_7c81.0: IO Pin 034 (P2-23): IOPort
hm2/hm2_7c81.0: IO Pin 035 (P2-25): IOPort
hm2/hm2_7c81.0: IO Pin 036 (J5-TXEN0): IOPort
hm2/hm2_7c81.0: IO Pin 037 (J6-TXEN1): IOPort
hm2/hm2_7c81.0: IO Pin 038 (P7-01): IOPort
hm2/hm2_7c81.0: IO Pin 039 (P7-02): IOPort
hm2/hm2_7c81.0: IO Pin 040 (P7-03): IOPort
hm2/hm2_7c81.0: IO Pin 041 (P7-04): IOPort
hm2/hm2_7c81.0: IO Pin 042 (P7-05): IOPort
hm2/hm2_7c81.0: IO Pin 043 (P7-06): IOPort
hm2/hm2_7c81.0: IO Pin 044 (P7-07): IOPort
hm2/hm2_7c81.0: IO Pin 045 (P7-08): IOPort
hm2/hm2_7c81.0: IO Pin 046 (P7-09): IOPort
hm2/hm2_7c81.0: IO Pin 047 (P7-11): IOPort
hm2/hm2_7c81.0: IO Pin 048 (P7-13): IOPort
hm2/hm2_7c81.0: IO Pin 049 (P7-15): IOPort
hm2/hm2_7c81.0: IO Pin 050 (P7-17): IOPort
hm2/hm2_7c81.0: IO Pin 051 (P7-19): IOPort
hm2/hm2_7c81.0: IO Pin 052 (P7-21): IOPort
hm2/hm2_7c81.0: IO Pin 053 (P7-23): IOPort
hm2/hm2_7c81.0: IO Pin 054 (P7-25): IOPort
hm2/hm2_7c81.0: IO Pin 055 (P5-RX0): IOPort
hm2/hm2_7c81.0: IO Pin 056 (P6-RX1): IOPort
hm2/hm2_7c81.0: registered
note: MAXV max: 30.000 units/sec 1800.000 units/min
note: LJOG max: 30.000 units/sec 1800.000 units/min
note: LJOG default: 30.000 units/sec 1800.000 units/min
note: jog_order='XYZ'
note: jog_invert=set([])

Thanks PCW!

I have installed the 2.9 release, but the 7c81 card maybe need the latest update.
I'll update LinuxCNC to the last revision as you recommend.

Thanks!

Hi PCW

I try to install LinuxCNC from source on my RPi3 from this guide with just a minor changes:
gnipsel.com/linuxcnc/uspace/rpi4-emc.html

But when I run:
debuild -uc -us

I get the following error:
virtual memory exhausted: Cannot allocate memory
Makefile:227: recipe for target 'objects/emc/rs274ngc/interp_python.o' failed
make[1]: *** [objects/emc/rs274ngc/interp_python.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make[1]: Leaving directory '/home/pi/emc/src'
debian/rules:31: recipe for target 'build-stamp' failed
make: *** [build-stamp] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
debuild: fatal error at line 1116:
dpkg-buildpackage -rfakeroot -us -uc failed

My changes:

1 - I checkout this:
git checkout master
instead of:
git checkout 2.8

2 - I did not need to modify debian/configure, it was ok:
Debian-10|Debian-10.*|Raspbian-10|Raspbian-10.*)
Or maybe do I have to change this to:
Debian-10|Debian-10.*|Raspbian-9|Raspbian-9.*)

3 - I did not remove the following lines from debian/control.bottom.in. I chose to keep it original just in case:
python-gtksourceview2,
python-vte,
Maybe do I have to remove this lines to my RPi3?

4 - When I run:
debian/configure uspace
It reports this:
successfully configured for 'uspace-Raspbian-9.11'-'uspace'...
instead of:
successfully configured for 'uspace-Raspbian-10'-'uspace'...

Could the Raspbian-9.11 be the problem?
Or maybe is the RPi3 virtual memory not enough?

I try all this exactly on my RPi4 and everything runs fine!

Thanks!