fan: add enable_pin option (#5732)

Signed-off-by: Lasse Dalegaard <dalegaard@gmail.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md
index 833e1457..90bf1770 100644
--- a/docs/Config_Reference.md
+++ b/docs/Config_Reference.md
@@ -2520,6 +2520,12 @@ pin:
 #   enough for fans below 10000 RPM at 2 PPR. This must be smaller than
 #   30/(tachometer_ppr*rpm), with some margin, where rpm is the
 #   maximum speed (in RPM) of the fan.
+#enable_pin:
+#   Optional pin to enable power to the fan. This can be useful for fans
+#   with dedicated PWM inputs. Some of these fans stay on even at 0% PWM
+#   input. In such a case, the PWM pin can be used normally, and e.g. a
+#   ground-switched FET(standard fan pin) can be used to control power to
+#   the fan.
 ```
 
 ### [heater_fan]
@@ -2541,6 +2547,7 @@ a shutdown_speed equal to max_power.
 #tachometer_pin:
 #tachometer_ppr:
 #tachometer_poll_interval:
+#enable_pin:
 #   See the "fan" section for a description of the above parameters.
 #heater: extruder
 #   Name of the config section defining the heater that this fan is
@@ -2577,6 +2584,7 @@ watched component.
 #tachometer_pin:
 #tachometer_ppr:
 #tachometer_poll_interval:
+#enable_pin:
 #   See the "fan" section for a description of the above parameters.
 #fan_speed: 1.0
 #   The fan speed (expressed as a value from 0.0 to 1.0) that the fan
@@ -2622,6 +2630,7 @@ information.
 #tachometer_pin:
 #tachometer_ppr:
 #tachometer_poll_interval:
+#enable_pin:
 #   See the "fan" section for a description of the above parameters.
 #sensor_type:
 #sensor_pin:
@@ -2679,6 +2688,7 @@ with the SET_FAN_SPEED [gcode command](G-Codes.md#fan_generic).
 #tachometer_pin:
 #tachometer_ppr:
 #tachometer_poll_interval:
+#enable_pin:
 #   See the "fan" section for a description of the above parameters.
 ```