Windows embedded (7) - repurposing a thin client PC

[Kitwn]

m-c,
My understanding is that the best controllers are simply taking their control data and the raw G-code from the PC and generating all the control pulses themselves without having any of the other calls on their processor that go with running an operating system at the same time. This has to be the best way to go in terms of optimum pulse timing but is also the more expensive option. Being able to download a G-code file via ethernet and let it run while the computer is used for other purposes is also an advantage of these more modern designs and is definitely the best way to go both technically and for ease of operation and throughput of work.

My recommendation of LinuxCNC on an old PC is primarily aimed at budget conscious hobbyists like myself. It's cheap, it works, it lets you concentrate the available budget on the mechanical hardware when you first get going. Then you can start making things while you learn just how many worms there are in the CNC can

I use a dedicated PC running only LinuxCNC and did some measurements of step pulse timing a while back. What should have been a continuous stream of pulses at 125uS intervals had most pulses at 125uS but a fairly regular pattern of intervals of 100uS and 150uS as well. There isn't any obvious vibration on the machine, but this is the only CNC machine I have ever used of so haven't any experience of perfectly timed pulses to compare it with.

In the unlikely event of finding myself with nothing else to do I could try building an oscillator to produce a well timed series of pulses and make a comparison but that's not going to happen anytime soon.

Kit

PS Doddy: Saw your reply after finishing the above blather. LinuxCNC is fairly easy to get going if you build a vanilla 4 motor machine and will run perfectly well on an old Windows-XP era motherboard. The LinuxCNC forum is very helpful.