Execution Order

A block (line of G-code) consists of a sequence of words. The programmed order of words is not considered by the GST interpreter. Instead, the following execution order is obeyed that consists of 7 sequential and dependent steps.

1. Reference System

 

N*

 

Set block number.

 

 

 

G17..G19

 

Selection of a workingplane.

 

 

 

G70, G71, G700, G710

 

Selection of a unit.

 

 

 

G90, G91

 

Selection of absolute/ incremental programming.

 

 

 

D*, P*

 

Selection of a tool and its orientation.

 

2. Configuration

 

G40..G42

 

(De-)activation of Tool Radius Compensation.

 

 

 

G53..G59

 

Selection and programming of zero offset shift.

 

 

 

F*

 

Set velocity.

 

3. M-Function Pre

 

M*

 

M-functions that are configured as “before”.

 

4. Parameter to PLC

 

H*, S*, T*

 

 

 

5. Movement

 

Q*, G00..G03

 

Movement to a point.

 

 

 

G09, G60

 

Activation of accurate stop.

 

6. Wait

 

G04

 

Wait for a given duration.

 

7. M-Function Post

 

M*

 

M-functions that are configured as “after”.

 

The first step sets up the reference system. The second step configures following movements. Note that the second step may depend on the first one. E.g. the programmed velocity (F) considers a velocity unit (G700) that is programmed in the same block. Step three and the following steps perform actions like a movement.