Hi,
Mach4, like Mach3 that preceeds it run on Windows platforms, and Windows is not nor is ever likely to be realtime.
Windows uses the interrupt system VERY extensively for its own purposes and therefore any application, Mach4 say, cannot be realtime because
Windows has priority. Mach4 is a buffered control solution. With a well sorted and powerful PC you might get the buffering time down to 20-30 milliseconds,
but still there is a delay.
When you say you want realtime performance....what do you mean?. Could your control strategy accommodate delays of this magnitude?
You might be advised to investigate LinuxCNC. The current Linux distro that is used is Debian with Realtime Pre-empt Kernel. Any reasonable PC should be able
to manage 5usec jitter....would that be fast enough?
Craig