[Ekaros]

Remember that CNC is programming environment. Now how do actually see what program is loaded? Or where is the execution at the moment? For anything beyond few lines of text on dotmatrix screen actual OS starts to be come desirable.

And all things considered, Windows is not that bad option. Anything else would also have issues. And really what is your other option some outdated, unmaintained Android? Does your hardware vendor offer long term support for Linux?

Windows actually offers extremely good long term support quite often.

[bschwindHN]

> And all things considered, Windows is not that bad option

I'm gonna go out on a limb and say that it actually is. It's a closed source OS which includes way more functionality than you need. A purpose-built RTOS running on a microcontroller is going to provide more reliability, and if you don't hook it up to the internet it will be more secure, too. Of course, if you want you can still hook it up to the internet, but at least you're making the conscious decision to do so at that point.

Displaying something on a screen isn't very hard in an embedded environment either.

I have an open source printer which has a display, and runs on an STM32. It runs reliably, does its job well, and doesn't whine about updates or install things behind my back because it physically can't, it has no access to the internet (though I could connect it if I desired). A CNC machine is more complex and has more safety considerations, but is still in a similar class of product.

https://youtu.be/FxIUs-pQBjk?si=N-W-Af6jBgGBiIgl&t=46

[cjbillington]

> Does your hardware vendor offer long term support for Linux?

This seems muddled. If the CNC manufacturer puts Linux on an embedded device to operate the CNC, they're the hardware manufacturer and it's up to them to pick a chip that's likely to work with future Linuxes if they want to be able to update it in the future. Are you asking if the chip manufacturer offers long-term-support for Linux? It's usually the other way around, whether Linux will support the chip. And the answer, generally, is "yes, Linux works on your chip. Oh you're going to use another chip? yes, Linux works on that too". This is not really something to worry about. Unless you're making very strange, esoteric choices, Linux runs on everything.

But that still seems muddled. Long-term support? How long are we talking? Putting an old Linux kernel on an embedded device and just never updating it once it's in the field is totally viable. The Linux kernel itself is extremely backwards compatible, and it's often irrelevant which version you're using in an embedded device. The "firmware upgrades" they're likely to want to do would be in the userspace code anyhow - whatever code is showing data on a display or running a web server you can upload files to or however it works. Any kernel made in the last decade is going to be just fine.

We're not talking about installing Ubuntu and worrying about unsolicited Snap updates. Embedded stuff like this needs a kernel with drivers that can talk to required peripherals (often over protocols that haven't changed in decades), and that can kick off userspace code to provide a UI either on a screen or a web interface. It's just not that demanding.

As such, people get away with putting FreeRTOS on a microcontroller, and that can show a GUI on a screen or a web interface too, you often don't need a "full" OS at all. A full OS can be a liability, since it's difficult to get real-time behaviour which presumably matters for something like a CNC. You either run a real-time OS, or a regular OS (from which the GUI stuff is easier) which offloads work to additional microcontrollers that do the real-time stuff.

I did not expect Windows to be running on CNCs. I didn't expect it to be running on supermarket checkouts. The existence of this entire class of things pointlessly running self-updating, internet-connected Windows confuses me. I can only assume that there are industries where people think "computer equals Windows" and there just isn't the experience present, for whatever reason, to know that whacking a random Linux kernel on an embedded computer and calling it a day is way easier than whatever hoops you have to jump through to make a desktop OS, let alone Windows, work sensibly in that environment.

[Ekaros]

5-10 years is not unreasonable expected support I think.

And if you are someone manufacturing physical equipment be it CNC machine or vehicle lift hiring entire team to keep Linux patched and making your own releases seems pretty unreasonable and waste of resources. In the end anything you choose is not error free. And the box running software is not main product.

This is actually huge challenge. Finding vendor that can deliver you a box where to run software with promised long term support, when the support is actually more than just few years.

Also I don't understand how it is any more acceptable to run unpatched Linux in networked environment than it is Windows. These are very often not just stand-alone things, but instead connected to at least local network if not larger networks. With possible internet connections too. So not updating vulnerabilities is as unacceptable as it would be with Windows.

With CNC there is place for something like Windows OS. You have separate embedded system running the tools. But you still want a different piece managing the "programs". As you could have dozens or hundreds of these. And at that point reading them from network starts once again make sense. Time of dealing with floppies is over...

And with checkouts, you want more UI than just buttons. And Windows CE has been reasonably effective tool in that.

Linux is nice on servers, but often with embedded side keeping it secure and up to date is massive amount of pain. Windows does offer excellent stability and long term support. And you can just simply buy a computer with sufficient support from MS. One could ask why do not not massive companies run their own Linux distributions?

[cyberax]

> 5-10 years is not unreasonable expected support I think.

A couple of years ago, I helped a small business with an embroidery machine that runs Windows 98. Its physical computer died, and the owner could not find the spare parts. Fortunately, it used a parallel port to control the embroidery hardware, so it was easy to move to a VM with a USB parallel port adapter.

[pdw]

That was very lucky then. USB parallel ports adapters are only intended to work with printers. They fail with any hardware that does custom signalling over the parallel port.

[tormeh]

Ok, just make the lift controller analogue. No digital processors at all. Nothing to update, so no updates needed.

[Ekaros]

Maybe you want your lift to be able to diagnose itself. Tell possible faults, instead of spending man hours on troubleshooting every part each time downtime included. With big lifts there are many parts that could go wrong. Being able to identify which one saves lot of time and time is money.

These sort of outages are actually extremely rare nowadays. Considering how long these control systems have been kept around must mean that they are not actually causing that many issue that replacing them would be worth it.