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Why make it so complicated?

Just use CN1.
Simply connect the home switch DI3 and COM pin 13 here. Use the wiring diagram on page 47 for the external power supply.
Use homing mode 4 or 6, depending on where your home switch is located.
If everything works and you have encoder cables with batteries, you can switch everything over to multiturn absolute encoders—which don’t require homing—by following the instructions above.

I wrote these instructions because there are issues with XYYZ (gantry) axes. 
Explanation:
During CIA402 homing, control and monitoring of the axes are taken away from LinuxCNC. The internal servo homing is triggered. You can only see the current position of the axes and how they are moving. Once the axes have found their home position and report that they are ready, control is returned to LinuxCNC. This results in several problems that can become dangerous!
1. After homing is complete, the axes may jump, leading to an error. This has already happened to you.

2. With gantry axes, there are synchronization issues. It can happen that one axis starts moving late or not at all. In the worst case, the gantry will be crooked or break.

3. Once homing has started, it cannot be interrupted.
Neither an emergency stop, a reset, nor disabling the enable signal will help. The servos will start moving on their own once they’re enabled again. The only solution is to turn the servos off and then back on!

Using LinuxCNC homing isn’t an option either.
The Z-index pulse isn’t output by the servos and isn’t available. Of course, you can also use LinuxCNC homing by moving to the home switch or limit switch the traditional way, but that’s imprecise and suitable only for a cheese cutter at best.

That’s why I wrote this guide.
Here are the steps again:
1. Get everything up and running. If you run into problems, there are many threads here that can help, or you can start a new thread.
2. Get CIA homing to work with the servos removed.
3. Convert the servos to multiturn absolute encoders following my instructions.
4. Install the servos and, on the gantry, make sure they don’t twist—otherwise your gantry will be crooked.

 

It also (i just discovered) omits the G43 after a tool change, which is likely to cause trouble.

This is rather annoying as G28 U0 is very much not a LinuxCNC style thing.
It's valid G-code but I don't imagine very many LinuxCNC lathes are using the U and W axes.

Yes, it seems to be the case. I seem to have better luck when deleting position file prior to opening linuxCNC and homing, it works without issue most of the times. The issue i had with the Z motor turned out to be a slight misunderstanding of the process on my side, i still don't have a z axis and I was simulating the homing switch hits triggering the sensor manually, but turns out the process needs the sensor to become hit again on the second pass before it'll attempt to look for the z pulse.

@andrax are you on an XYYZ machine like your posted config suggests? can you respond regarding how the Ys sync up with the absolute encoder? The other thing i'm concerned about is if I should use homing mode 20 instead of 4 for Y, because otherwise the z pulse step becomes something that'll mess up your parallelism without you being able to adjust by adjusting the sensor triggers

Regarding the post above:
Yes, you're right,
CIA homing isn't really well documented yet.

In principle, it works like this:
The CIA-home function triggers the servos' internal homing routine and monitors the status. Once the servos report completion, CIA-home signals to LinuxCNC that homing is finished.

The drive error after homing is normal.
This happens when CIA-home hands control back to LinuxCNC.
Make sure the lowest feed rate is set; the axes will then synchronize without errors.

For plasma and starting with LinuxCNC with stepper motors, I would get a Mesa 7i96s and a Mesa THCAD2 to read the torch voltage. Also get a Meanwell MDR-60-24 24 volt power supply for field power and a Meanwell MDR-10-5 5 volt power supply for logic. When you order your Mesa gear also get some of their DIN rail mounts and a couple of COMMX2 bus bars. That will set you up for a running start.

SoloRev wrote:

The issue seems to be DKMS failing with the latest debian kernel. I couldn’t figure out how to uninstall the kernel but I was able to stop it from being installed on a new system. Before you do a 

sudo apt upgrade. stop any kernel update with [code]sudo apt-mark hold *6.12* basically wildcard the 6.12 string on both sides to prevent anything related to the kernel from being updated. 

[/code]

Did you try the revised instructions in the first post?

The example code can be used inside a python remap and the handler could read the file with the parameter values but the remap itself would have to be called from inside the gcode program which is currently executing.
So if you wanted your parameter page to reflect changes coming from the gcode program you would need to insert the remap after every parameter assignment in the gcode.

Thanks for the reply, it's all a bit overwhelming the information on the site when you have no Linux experience at all.

forum.linuxcnc.org/plasma-laser/38974-di...rything-in-one-place

forum.linuxcnc.org/show-your-stuff/38547...-5m-cnc-plasma-build

forum.linuxcnc.org/plasma-laser/35349-cn...lding-info-and-guide

And laptops are not usually preferred for running LinuxCNC due to inherent power saving features that cause latency issues.
Having said that, here are some that do work:
forum.linuxcnc.org/18-computer/54369-use...mesa-ethernet-boards

And some used and new PC's tested with LinuxCNC
forum.linuxcnc.org/18-computer/38838-har...ency-tests-used-pc-s

Hi,
New to the forum and new to cnc. I am building a CNC plasma cutting table based on plans from Homemade Madness however, I would like to use LinuxCNC instead of Mach3 as in the plan. I have not bought any of the motors or controllers yet so was hoping to get some advice before purchasing anything. I plan to use an old laptop for the install of Linux and LinuxCNC so am also looking for suggestions for the best version of Linux to use. Thanks in advance for any suggestions, help.

Would there be a way for the python handler for the vcp, to call or reference to python remap script that can access the interpreter variables?  With as little python programming skill as i have this seems like it could be possible, I wouldn't know if that is completely impossible, or not any better than writing to an intermediary file.

The issue seems to be DKMS failing with the latest debian kernel. I couldn’t figure out how to uninstall the kernel but I was able to stop it from being installed on a new system. Before you do a . stop any kernel update with basically wildcard the 6.12 string on both sides to prevent anything related to the kernel from being updated. 

I'm a little disappointed that there is no way to read/monitor them directly, but I was coming to that conclusion. Now to figure out the best work aroud. I'll probably end up trying to do what you suggest. Thanks for your help.

This example code will read parameters 5200..5299 and write the values to a file 'log.txt', in a next step you would read the file and extract the values to initialize the spin boxes: