Minimum Fan Speed Override

minimum_fan_speed.cfg

# -------------------------------------------------------------------------- #
#                         MINIMUM FAN SPEED OVERRIDE                         #
# -------------------------------------------------------------------------- #
# Override the default fan speed to set a minimum floor                      #
#   and adjust the values to fit the new range.                              #
# Examples: (with min_fan_speed = 128)                                       #
#   M106 S255 ; set fan speed to 255                                         #
#   M106 S25  ; set fan speed to 159                                         #
#   M106 S0   ; set fan speed to 0                                           #
#   M106 S50  ; set fan speed to 128                                         #
#   M106 S75  ; set fan speed to 191                                         #
# -------------------------------------------------------------------------- #
[gcode_macro M106]
variable_min_fan_speed: 128
rename_existing: M106.0
description: Set fan speed
gcode:
    {% set initial_speed = params.S|default(0)|float %} ; Get the initial speed value
    {% if initial_speed < 0 %} ; If the initial speed is less than 0
        {% set initial_speed = 0 %} ; Set the initial speed to 0
    {% elif initial_speed > 255 %} ; If the initial speed is greater than 255
        {% set initial_speed = 255 %} ; Set the initial speed to 255
    {% endif %}
    ; Calculate the new speed value
    {% set new_speed = (initial_speed / 255 * (255 - min_fan_speed)) + min_fan_speed %}
    {% if new_speed > 255 %} ; If the new speed is greater than 255
        {% set new_speed = 255 %} ; Set the new speed to 255
    {% elif new_speed <= min_fan_speed %} ; If the new speed is less than or equal to the minimum fan speed
        {% set new_speed = 0 %} ; Set the new speed to 0
    {% endif %}
    M106.0 S{new_speed} ; Set the fan speed to the new speed