ACU-RITE CNC 3500i - Manual (Page 160)

134 7 Programming: Canned Cycles, sub-programs
7.
1 Explaining Basic Cy
cles
Using Arc Center and EndPoint to create a circle
Since the start point and end point of a circle are the same, you do not
need to program an end point to create a circle. Position the tool at the
required starting point before you execute the arc move.
Omit the end point parameters for X and Y.
Conversational example: Arc CCW XCenter 0 YCenter .5
G-code example: G91 G3 I0 J.5
Arc Move - Center and Angle, Absolute mode:
Arc Move - Center and Angle, Incremental mode:
Programming a full circle is not possible when using the
XYR (Radius and EndPoint) format.