cool shutdown

[controller_fan Main_Power]
pin: PB0
max_power: 1
off_below: 1
shutdown_speed: 0 # Power off when shutdown
idle_timeout: 1 # Fast timeout unless steppers or a heater is live
heater: extruder, heater_bed

[delayed_gcode cooldown]
# The heater needs a setpoint to keep the 24v PSU online as a "controller_fan"
# Since this doubles as our hot-end fan power on many common printers 
# we don't want main power deactivated until there's no longer a risk of heat creep.
# Targets below 10c are treated as a countdown timer in seconds.
initial_duration: 0.1
gcode:
 {% if printer.extruder.target == 0 and printer.extruder.temperature > 150 %}
 SET_HEATER_TEMPERATURE HEATER=extruder TARGET=1
 {% elif printer.extruder.target > 0
    and printer.extruder.target < 10
    and printer.extruder.temperature <= 150 %}
 SET_HEATER_TEMPERATURE HEATER=extruder TARGET={printer.extruder.target-1}
 {% endif %}
 UPDATE_DELAYED_GCODE ID=cooldown DURATION=1

[gcode_macro G28]
rename_existing: C28
gcode: CUSTOM_G28{' X=X' if params.X is defined}{' Y=Y' if params.Y is defined}{' Z=Z' if params.Z is defined}

# "Enable" a heater by setting it to 2c and wait 2 seconds for PSU warmup before trying to init/move steppers.
# This is a hack to work around Klipper trying to initialize TMC chips before they have fully powered up.
[gcode_macro CUSTOM_G28]
gcode:
{% if printer.toolhead.homed_axes == '' %}
{action_respond_info("Powering up steppers...")}
{% if printer.extruder.target == 0 %}
SET_HEATER_TEMPERATURE HEATER=extruder TARGET=2
{% endif %}
G4 P2000
{% endif %}
C28 {params.X|d('')} {params.Y|d('')} {params.Z|d('')}