The G-functions

The so-called "G"-functions describe the type of the traverse movement, interpolation type, measuring method, the time-related influence and activating of certain operation states. The syntax is:

G <expr> 

For the G-functions, there are a variety of differentiating characteristics:

• Effectiveness: There are G-functions that have validity after their programming in their meaning only for the respective block (non-modal) and those which are active after the very initial programming in their meaning until they are explicitly deselected (modal).
• Exceptions: Certain G-functions mutually exclude themselves. For instance, G01 (linear interpolation) and G02 (circular interpolation) cannot be simultaneously selected. Therefore the functions summarized in these groups must not be programmed commonly in one NC-block:

A modal function is automatically deselected, if, in a following block, another function of the same group is selected.

Programming example

:
N50 G01 X100 Y200 (Linear interpolation active)
N60 G41 X200 Y200 (Linear interpolation active)
N50 X300 Y250 (Linear interpolation active)
N50 X100 Y50 (Linear interpolation active)
N50 G02 X100 Y50 I100 (Circular interpolation active)
:

• Basic position: During switching, after RESET, or at program end, the control finds itself in the basic position. In this basic position, already a few G-functions are active without explicit selection.