M303 - PID autotune

thermal Auto-tune the PID system to find stable values. PIDTEMP|PIDTEMPBED


This command initiates a process of heating and cooling to determine the proper PID values for the specified hotend or the heated bed.


View current PID values with M503.

If EEPROM_SETTINGS is enabled, all PID values are saved with M500, loaded with M501, and reset with M502.


M303 [C<count>] [D] [E<index>] [S<temp>] [U<bool>]



Cycles. At least 3 cycles are required. Default 5.


    Toggle PID debug output on / off (and take no further action). (Requires PID_DEBUG)


      Hotend index (-1 for heated bed). Default 0.


        Target temperature


          Use PID result. (Otherwise just print it out.)


            Auto-tune hotend at 210 °C for 8 cycles:

            M303 E0 C8 S210

            Auto-tune bed at 60 °C for 8 cycles:

            M303 E-1 C8 S60