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A workaround if you are worried about phase error on reversal is to use a tension-comopression tap holder to absorb the axial mismatch.

Anything HAL in GTK will have come with the LinuxCNC installation.

It _might_ help to install linuxcnc-uspace-dev (it won't hurt, at least)

LinuxCNC _is_ a motion controller, and can support a wide range of servo types. You are almost certainly going to need a better interface than the parallel port, but there are options to work with all sorts of (possibly second hand) servos and drivers using step/dir or analogue voltage control, and with encoder or resolver feedback.

There is definitely an advantage in a commercial setting of having drop-in replacement hardware readily available, though.

The things that can be displayed are:
Using POSIX non-realtime (this is bad)
Using Posix reatlime (this is fine, it means that you are using a preempt-rt kernel)
Using LXRT realtime (this is fine too, but is pretty rare, it means you are using LinuxCNC-uspace with an RTAI or Xenomai kernel)
<Nothing> Probably means that you are using RTAI, which is also fine.

Aha, many thanks for your speedy response.

There is currently no "missing tooth index" support in hostmot2
(there is experimental firmware but no driver support currently)

 

Hey i installed the 2025 linux cnc distribution and i am getting new problems.

i am using mesa 7i96s, with ip 10 10 10 10. my pc  i set up the ip to 10 10 10 100 using the following commands:
sudo ip addr flush dev enp6s0
sudo ip adr add 10 10 10 100/64 dev enp6s0
sudo ip link set dev ensp6s0 up

(using this method was kinda buggy)
i tried setting up the static ip address another was as well with the interface file:
auto enp6s0
iface enp6s0 inet static
address 10.10.10.11
hardware-irq-coalesce-rx-usecs 0

but i cant connect to the internet like this

after this i can ping the card as well as set up the pnc conf. i am able to control motors.
when i save the configuration i try to open it from the desktop launcher and i get an error i am attatching the report

Print file information:
RUN_IN_PLACE=no
LINUXCNC_DIR=
LINUXCNC_BIN_DIR=/usr/bin
LINUXCNC_TCL_DIR=/usr/lib/tcltk/linuxcnc
LINUXCNC_SCRIPT_DIR=
LINUXCNC_RTLIB_DIR=/usr/lib/linuxcnc/modules
LINUXCNC_CONFIG_DIR=
LINUXCNC_LANG_DIR=/usr/lib/tcltk/linuxcnc/msgs
INIVAR=inivar
HALCMD=halcmd
LINUXCNC_EMCSH=/usr/bin/wish8.6
LINUXCNC - 2.9.4
Machine configuration directory is '/home/cnc/linuxcnc/configs/RUTER_2_5_25'
Machine configuration file is 'RUTER_2_5_25.ini'
INIFILE=/home/cnc/linuxcnc/configs/RUTER_2_5_25/RUTER_2_5_25.ini
VERSION=1.1
PARAMETER_FILE=linuxcnc.var
TPMOD=
HOMEMOD=
TASK=milltask
HALUI=halui
DISPLAY=axis
COORDINATES=XYZ
KINEMATICS=trivkins coordinates=XYZ
Starting LinuxCNC...
Starting LinuxCNC server program: linuxcncsvr
Loading Real Time OS, RTAPI, and HAL_LIB modules
Starting LinuxCNC IO program: io
Starting HAL User Interface program: halui
linuxcnc TPMOD=tpmod HOMEMOD=homemod EMCMOT=motmod
Found file(REL): ./RUTER_2_5_25.hal
Shutting down and cleaning up LinuxCNC...
Running HAL shutdown script
hm2: loading Mesa HostMot2 driver version 0.15
hm2_eth: loading Mesa AnyIO HostMot2 ethernet driver version 0.2
hm2_eth: ERROR: Could not retrieve hardware address (MAC) of 10.10.10.10: Resource temporarily unavailable
hm2: unloading
Removing HAL_LIB, RTAPI, and Real Time OS modules
Removing NML shared memory segments

Debug file information:
Note: Using POSIX realtime
hm2_eth: rtapi_app_main: Resource temporarily unavailable (-11)
./RUTER_2_5_25.hal:9: waitpid failed /usr/bin/rtapi_app hm2_eth
./RUTER_2_5_25.hal:9: /usr/bin/rtapi_app exited without becoming ready
./RUTER_2_5_25.hal:9: insmod for hm2_eth failed, returned -1
1734
Stopping realtime threads
Unloading hal components
Note: Using POSIX realtime



 

Yes, that should work fine.

There is mention in the HAL of closed-loop steppers. Does this mean that you are closing the position loop in LinuxCNC HAL with encoders and PID (you clearly _are_ doing this) but do you also have closed-loop stepper drivers that also read the encoders?

It is possible that your problem is due to cascaded controllers.

I would be tempted to try a making an alternate config without the DPLL and with the stepgens in position mode, directly driven by motor-pos-cmd. Having a PID in HAL ought to give better results, but if the problem goes away with a more "classic" config then that at least suggests somewhere to look.

Originally my lathe had an encoder attached to the spindle head. 

My new spindle motor servo driver has an encoder output. Servo is geared 1to1 with the spindle. 

I’m assuming that will be enough fore position control.

I using a 7i96 board.
 

I think I have the system in control now, and have reached the point where I want to add an encoder to the spindle for rigid tapping and better speed control.
My plan had been to add a toothed wheel with a pair of hall effect sensors, one a few teeth away, but half a cycle out of phase for quadrature, and a third for an index. Then connect these directly into the 7i77 channel 5 encoder inputs. (some biasing resistors maybe required also)
The maximum spindle rpm is 3500. I was proposing 40 teeth, but on say an M6 thread with 1mm pitch, I think that's a possible pitch error of .00625mm, which is pretty small, but I guess 100 would be better. I'd appreciate others opinions on this choice please.
Secondly, because of the belt run and lack of clearance around the belt pulley, putting the index tooth on is a much bigger mission than I was expecting.
Can I simply delete it and use a missing tooth, or pair of missing teeth as the index?
What looks to me like it might not so simply work is the encoder quadrature when it reaches the missing tooth, or am I over thinking this?
Thanks

Maybe lcec doesn't find the device or it doesn't go to OP.
From "ethercat slaves", are they in OP?
In halshow, can you see the pin lcec.0.0.statusword?
Any clues from "sudo dmesg", the last say 50 lines are of interest.

Edit. I looked a bit closer at the ethercat-conf.xml file.
You have double info, which I haven't seen before. Where does the info in that file come from?
I am not used to see a lot of PDOs in syncManager 0 and 1, but always have the PDOs
in SM 2 and SM 3. And you have the info there as well.

Can you test to replace the contents in ethercat-conf.xml of the clients with this

github.com/LinuxCNC/linuxcnc/pull/2722

Seems like a better solution if possible.

How adventurous do you feel?

github.com/LinuxCNC/linuxcnc/pull/2722

you need to execute 'lcnc_logger.py' with linuxcnc running. This can also be done using a custom mcode as outlined here (note that the file has since been renamed to 'lcnc_logger.py') :
forum.linuxcnc.org/21-axis/30986-axis-po...gger?start=60#294514