Hi, Mario
It's a good habit to get into, Most if not all Cam software allows it.
O1000
G54 G94 G90 G21
M6 T1
G43 H01 G0 Z50
G0 X0 Y0
M98 P2000 L50 ;M98 P50 2000, P2000 calls O2000, L50 repeat's it 50 times
G80
G0 Z10
M30
% ;You can put it hear also
O2000
G81 R2 Z-12
G91 X5
G90 M99
% ;Need this or blank line feed
Glad I could help, Chip