PCB Heaven

General Category => Maths, Geometry, Physics and others => Topic started by: stamatis on August 23, 2008, 20:31:33 PM

Title: CNC machine - Select between Inch and Metric units - G20 G21
Post by: stamatis on August 23, 2008, 20:31:33 PM
As you may have notice in previous topics, our test machine measures in Metric units, meaning in millimeters. But this can change. You may change the units system using the commands G20 and G21 as follows:

G20 -> Inch units
G21 -> Metric units

These commands are straight forward. There should be no more comments for these only a more complicated example:

Quote
N1 G90 G21
With this code the machine will start in absolute programming in metric units
As you can understand, you can run more than one G command in each line:

Quote
N1 G91 G20 G0 Y100 Y100

Which means that the machine will start in incremental programming using inch units and will make a rapid linear motion.