Subroutines in myCNC are done in a manner similar to other industrial CNC systems.

Sample code of a G-code program containing subroutines #100 and #101:

g90 g0 z10  F500
#100=[10]
#101=[10]
G0 x#100 y#101
m98 P101 L5
m2
o100
g0 x#100y#101
g1z0
g2 x#100 y#101 i10
#100=[#100+40]
g0 z10
m99
o101
M98 P100 L5
#100=[10]
#101=[#101+40]
M99