Two Machines from one PC

[Neale]

...and to put some numbers on that, at 750mm/min, Mach3 will be driving that parallel port at, maybe, 2000 pulses per second. 10 msec delay while the cpu is doing something for the other job means that 20 pulses will be delayed or maybe even lost. At best that means rough running as the steppers are continually changing speed due to varying pulse rates and at worst missed steps and lost accuracy.

You originally asked for people with experience to respond. I suspect that you might have trouble finding anyone who runs like this because it's such a potentially dangerous way to go. You are even recommended to avoid things like internet browsing while running Mach3 for these reasons. Use a motion controller like a UC100 and you might be in with a chance as the device unloads a lot of the time-critical pulse generation from the PC.

[cropwell]

I am long term friends with owner of Computer Services Nottingham. If my Mach 3 PC crashed, I would get an old machine for free, that somebody has traded in and load it up with my software from the mirrored NAS box. I speak from experience. That way you get a PC good enough to run the fairly low demands of Mach3 and with a parallel port.

My systems are all networked and the Mach3 machine has the Internet Gateway disabled, so no stupid interruptions. All my Gcode is generated on my Win10 machine and filed in the NAS box, so a hard drive failure on the CNC machine has low impact.

Even my 3D Printer has a Wifi enabled SD card, so I can download to it easily.

[magicniner]

See how it goes, but a fundamental misunderstanding of how Mach3 works with the PP seems to be at the heart of the assumption that this will not be problematic.

[cropwell]

See how it goes, but a fundamental misunderstanding of how Mach3 works with the PP seems to be at the heart of the assumption that this will not be problematic.

In order to control the PP effectively Mach 3 has its own driver with high priority control of interrupts. That is why I endorse a separate machine. It simply takes control of the interrupts, which can severely affect any other software running.

[Boyan Silyavski]

Best would be 2 machine and no PC. Each machine its own controller. Why people love so much mach3 when dedicated controllers are so much better and cheap nowadays, i dont get it. Obviously the desire for suffering...

[ngwagwa]

And it works!
Ran both machines today cuting fresh air from the same PC for several hours without any issues. The only thing I still need to do is connect 2 keyboards and mice to the PC.

[cropwell]

And it works!
Ran both machines today cuting fresh air from the same PC for several hours without any issues. The only thing I still need to do is connect 2 keyboards and mice to the PC.

Then you will need a KVM, but be careful you get one that operates backwards as they are normally 1 Kb & Mouse for 2 PCs - you would be better off with a mechanically switched one. Like this one https://www.amazon.co.uk/Sienoc-Port...c-fefa6b9989e1 although the sockets are the wrong way round