heater: Support max_power setting for heaters

Change the mcu PWM value from an integer (0-255) to a float (0. - 1.).
Add support for limiting the maximum power (as measured over a
sufficiently long duration) to a particular heater.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/klippy/fan.py b/klippy/fan.py
index 98e73ba6..739af2f1 100644
--- a/klippy/fan.py
+++ b/klippy/fan.py
@@ -11,7 +11,7 @@ class PrinterFan:
         self.printer = printer
         self.config = config
         self.mcu_fan = None
-        self.last_fan_value = 0
+        self.last_fan_value = 0.
         self.last_fan_time = 0.
         self.kick_start_time = config.getfloat('kick_start_time', 0.1)
     def build_config(self):
@@ -20,15 +20,15 @@ class PrinterFan:
         self.mcu_fan = self.printer.mcu.create_pwm(pin, hard_pwm, 0)
     # External commands
     def set_speed(self, print_time, value):
-        value = max(0, min(255, int(value*255. + 0.5)))
+        value = max(0., min(1., value))
         if value == self.last_fan_value:
             return
         mcu_time = self.mcu_fan.print_to_mcu_time(print_time)
         mcu_time = max(self.last_fan_time + FAN_MIN_TIME, mcu_time)
-        if (value and value < 255
+        if (value and value < 1.
             and not self.last_fan_value and self.kick_start_time):
             # Run fan at full speed for specified kick_start_time
-            self.mcu_fan.set_pwm(mcu_time, 255)
+            self.mcu_fan.set_pwm(mcu_time, 1.)
             mcu_time += self.kick_start_time
         self.mcu_fan.set_pwm(mcu_time, value)
         self.last_fan_time = mcu_time