It then has to move 1 / 0.0005 = 2000 steps in the correct direction. Let’s say your machine moves in 0.0005″ steps. For example, if you want the machine to move to X0Y0Z0 and the machine is at X1Y0Z0, the X-axis has to move -1 to get to 0. Those simple motions go to the motion control portion of the program which is responsible for converting the simple motions into driver control signals. Give it a block of g-code (uploaded by the User Interface through a USB key, serial feed, FTP, or other means), and it knows how to convert that g-code into simple motions. The middle level is the g-code interpreter. Look at a CNC controller as consisting of 3 layers:ģ layers of function separation for CNC Controllers…Īt the top level is the human interface, the part that talks to the operator through the control panel. The key answer to getting industrial-grade CNC Control performance is that controls must separate the functions of low level motion control from the user interface and g-code interpreter.

How did these CNC Controls manage to get great results despite Windows and what’s the deal with Mach3? Some say it was one of the best CNC controllers ever made, but whether you agree with that assessment or not, it was clearly an industrial grade controller, and it was based on Windows NT. Consider the Siemens A2100 control, used on machines like the Cincinnati Arrow. Lest we think this is because machines are only recently powerful enough to allow Windows to work for CNC, let’s understand that building controllers on Windows is not even all that new an idea. Okuma’s THINC ®-OSP control is Windows-based… They tout their resulting open architecture as a big advantage, and THINC-OSP even lets you install apps as a result of its Windows underpinnings. We know that because there are many successful industrial CNC controls that are built on Windows. Okuma’s THINC ®-OSP control is Windows-based, for example. It turns out the idea that an industrial grade CNC controller can’t be built on top of Windows is false. How severe is this criticism of Mach3 and Windows? There are various other arguments against Mach3, such as the idea that the servo closed loop isn’t accessible to Mach3, but the big issue is the real time operating system issue. The logic goes on to say that because Windows is not a real time operating system, it’ll never be able to do industrial grade work. Many a forum post has carried the derisive view that Mach3 can’t be an industrial grade control because you can’t build “industrial grade” on top of Microsoft Windows.

Usb cnc motion controller mach4