The management of the code <PORTION...> has been modified to allow to perform a further split of the portion, in order to machine the first millimetres with parameters different from the  rest of the portion. It has been added the code DEEP (or DEPTH) to set the depth of the machining to be performed (positive value) or to set the depth of the machining to be skipped (negative value). For instance, <PORTION1/2,DEPTH3> will machine only the first 3 millimetres of the portion 1, while <PORTION1/2,DEPTH-3> > will machine the portion 1 avoiding the first 3 millimetres.

<PORTION1/2,DEPTH3>

Increment value in Z = 0.5

<PORTION1/2,DEPTH-3>

Increment value in Z = 1