1. G Function Description
1.2.14 G29: RETURN FROM REFERENCE
POSITION
Command form:
G29 X Y Z ;
X, Y, Z: specified coordinate；(absolute value in G90 mode, increment
value in G91 mode)
Description:
G29 can let tool from reference point through mid-point to specified
point after setting G28. Notice that G29 can not use alone, because G29
does not specify mid-point, G29 use the mid-point from G28, therefore,
before do G29 must do G28 first.
Under G90, the specified point is the absolute coordinate; under G91, it
is the increment distance from mid-point to specified point.
Example:
Y
C
Reference point
B mid-point(20,30)
A
D
X
Specified point(40,0)
1. Absolute command:
N001 G90 G28 X20.0 Y30.0;
//ABC, mid-point(20,40), in absolute command mode
N002 M06;//change the tool
N003 G29 X40.0 Y0.0;
// CBD, the specified point is absolute coordinate
2. Increment command:
N001 G91 G28 X20.0 Y40.0;
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