G21 (Metric)
G40 G90 G91.1
G64 P0.1
M03
S20000
F750
#1 = 20
#2 = 1
G00 X0 Y0 Z0
O100 do
G1 X#1
G1 Y#1
G1 X#2
G1 Y#2
#1 = [#1 - 1] 
#2 = [#2 + 1]
O100 while [#1 GT 10] 
M05
M30