T0
M116                            ; wait for hotend temp
G1 E20 F500                     ; Extrude 10mm slowly
G1 E-100 F1500                  ; Retract 100mm faster
G10 R0 S0                       ; set hotend temperature (R is standby)
M300 S1000 P100                 ; beep
M84 E0                          ; turn extruder motors off