Hi Ian
I think the correct answer is NONE of them.what 3 or 4 axis CAM package is capable of receiving information from a CAD file, and driving a stepper motor,
The big reason for this is because the companies which make CAD/CAM SW are NOT the companies which build machines, and vice versa.
And since every high-end machine is a bit different, you have to have a separation somewhere. That is at the g-code level.
It sticks in my mind that not every machine can take a g-code program and execute it. Some of them seem to use a proprietary in-house language of their own creation. Some sort of interactive language which goes with their massive control panel ... I may be wrong here - someone correct me if so.I assume all CNC stuff is driven by G code telling it where to go and for how long etc.
Look at web browsers and HTML. There was a 'standard' right at the start, promoted by several people including Mosaic, but then Microsoft decided to get in on the act and started creating their own incompatible version of HTML. So the first thing a web page (the HTML code) had to do is to do is ask what browser it was running under. Firefox? Sahara? Internet explorer? Opera? ... Fortunately. MS got told in no uncertain terms, and these days they do (mostly0 conform to the W3C standard.
Nope.why do we have so many cam packages doing the directing.......surely you go from A to B with the same information from the Cad drawing file?
Take a simple engineering drawing of a part and give it to 4 different workshop guys to build. Will each of them go through exactly the same set of steps in the same sequence to make the part? Extrremely unlikely. They will all go about it in different ways. It depends on how each of them likes to tackle a task. And so it is with CAM packages. Different SW designers order the machining operations in different sequences. In fact, one workshop guy might do the same task in several different ways, depending on what machines he has available at the time.
There are standards in the CAD and CAM worlds - and slowly more vendors are starting to conform to them. But they all have different approachs to the whole concept. It's still a jungle.
Cheers
Roger