stepper: Separate out homing code to its own PrinterHomingStepper class

Keep the homing code separate from the main stepper class.  This makes
it easier to verify the correct config parameters are provided.

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

4 files changed, 45 insertions, 42 deletions

diff --git a/klippy/cartesian.py b/klippy/cartesian.py
index f69855f6..d1747e6e 100644
--- a/klippy/cartesian.py
+++ b/klippy/cartesian.py
@@ -10,7 +10,7 @@ StepList = (0, 1, 2)
 
 class CartKinematics:
     def __init__(self, printer, config):
-        self.steppers = [stepper.PrinterStepper(
+        self.steppers = [stepper.PrinterHomingStepper(
             printer, config.getsection('stepper_' + n), n)
                          for n in ['x', 'y', 'z']]
         self.max_z_velocity = config.getfloat(
diff --git a/klippy/corexy.py b/klippy/corexy.py
index d429496c..1fdfa817 100644
--- a/klippy/corexy.py
+++ b/klippy/corexy.py
@@ -10,7 +10,7 @@ StepList = (0, 1, 2)
 
 class CoreXYKinematics:
     def __init__(self, printer, config):
-        self.steppers = [stepper.PrinterStepper(
+        self.steppers = [stepper.PrinterHomingStepper(
             printer, config.getsection('stepper_' + n), n)
                          for n in ['x', 'y', 'z']]
         self.steppers[0].mcu_endstop.add_stepper(self.steppers[1].mcu_stepper)
diff --git a/klippy/delta.py b/klippy/delta.py
index fd3705e3..8d8ecf04 100644
--- a/klippy/delta.py
+++ b/klippy/delta.py
@@ -14,7 +14,7 @@ SLOW_RATIO = 3.
 class DeltaKinematics:
     def __init__(self, printer, config):
         self.config = config
-        self.steppers = [stepper.PrinterStepper(
+        self.steppers = [stepper.PrinterHomingStepper(
             printer, config.getsection('stepper_' + n), n)
                          for n in ['a', 'b', 'c']]
         self.need_motor_enable = self.need_home = True
diff --git a/klippy/stepper.py b/klippy/stepper.py
index eac1d263..61900a20 100644
--- a/klippy/stepper.py
+++ b/klippy/stepper.py
@@ -13,6 +13,48 @@ class PrinterStepper:
         self.step_dist = config.getfloat('step_distance', above=0.)
         self.inv_step_dist = 1. / self.step_dist
         self.min_stop_interval = 0.
+        step_pin = config.get('step_pin')
+        dir_pin = config.get('dir_pin')
+        self.mcu_stepper = printer.mcu.create_stepper(step_pin, dir_pin)
+        self.mcu_stepper.set_step_distance(self.step_dist)
+
+        enable_pin = config.get('enable_pin', None)
+        if enable_pin is not None:
+            self.mcu_enable = printer.mcu.create_digital_out(enable_pin, 0)
+        self.need_motor_enable = True
+    def _dist_to_time(self, dist, start_velocity, accel):
+        # Calculate the time it takes to travel a distance with constant accel
+        time_offset = start_velocity / accel
+        return math.sqrt(2. * dist / accel + time_offset**2) - time_offset
+    def set_max_jerk(self, max_halt_velocity, max_accel):
+        # Calculate the firmware's maximum halt interval time
+        last_step_time = self._dist_to_time(
+            self.step_dist, max_halt_velocity, max_accel)
+        second_last_step_time = self._dist_to_time(
+            2. * self.step_dist, max_halt_velocity, max_accel)
+        min_stop_interval = second_last_step_time - last_step_time
+        self.mcu_stepper.set_min_stop_interval(min_stop_interval)
+    def motor_enable(self, move_time, enable=0):
+        if enable and self.need_motor_enable:
+            mcu_time = self.mcu_stepper.print_to_mcu_time(move_time)
+            self.mcu_stepper.reset_step_clock(mcu_time)
+        if (self.mcu_enable is not None
+            and self.mcu_enable.get_last_setting() != enable):
+            mcu_time = self.mcu_enable.print_to_mcu_time(move_time)
+            self.mcu_enable.set_digital(mcu_time, enable)
+        self.need_motor_enable = not enable
+
+class PrinterHomingStepper(PrinterStepper):
+    def __init__(self, printer, config, name):
+        PrinterStepper.__init__(self, printer, config, name)
+
+        endstop_pin = config.get('endstop_pin', None)
+        self.mcu_endstop = printer.mcu.create_endstop(endstop_pin)
+        self.mcu_endstop.add_stepper(self.mcu_stepper)
+        self.position_min = config.getfloat('position_min', 0.)
+        self.position_max = config.getfloat(
+            'position_max', 0., above=self.position_min)
+        self.position_endstop = config.getfloat('position_endstop')
 
         self.homing_speed = config.getfloat('homing_speed', 5.0, above=0.)
         self.homing_positive_dir = config.getboolean(
@@ -42,45 +84,6 @@ class PrinterStepper:
                 self.homing_stepper_phases = None
             if printer.mcu.is_fileoutput():
                 self.homing_endstop_accuracy = self.homing_stepper_phases
-        self.position_min = self.position_endstop = self.position_max = None
-        endstop_pin = config.get('endstop_pin', None)
-        step_pin = config.get('step_pin')
-        dir_pin = config.get('dir_pin')
-        mcu = printer.mcu
-        self.mcu_stepper = mcu.create_stepper(step_pin, dir_pin)
-        self.mcu_stepper.set_step_distance(self.step_dist)
-        enable_pin = config.get('enable_pin', None)
-        if enable_pin is not None:
-            self.mcu_enable = mcu.create_digital_out(enable_pin, 0)
-        if endstop_pin is not None:
-            self.mcu_endstop = mcu.create_endstop(endstop_pin)
-            self.mcu_endstop.add_stepper(self.mcu_stepper)
-            self.position_min = config.getfloat('position_min', 0.)
-            self.position_max = config.getfloat(
-                'position_max', 0., above=self.position_min)
-            self.position_endstop = config.getfloat('position_endstop')
-        self.need_motor_enable = True
-    def _dist_to_time(self, dist, start_velocity, accel):
-        # Calculate the time it takes to travel a distance with constant accel
-        time_offset = start_velocity / accel
-        return math.sqrt(2. * dist / accel + time_offset**2) - time_offset
-    def set_max_jerk(self, max_halt_velocity, max_accel):
-        # Calculate the firmware's maximum halt interval time
-        last_step_time = self._dist_to_time(
-            self.step_dist, max_halt_velocity, max_accel)
-        second_last_step_time = self._dist_to_time(
-            2. * self.step_dist, max_halt_velocity, max_accel)
-        min_stop_interval = second_last_step_time - last_step_time
-        self.mcu_stepper.set_min_stop_interval(min_stop_interval)
-    def motor_enable(self, move_time, enable=0):
-        if enable and self.need_motor_enable:
-            mcu_time = self.mcu_stepper.print_to_mcu_time(move_time)
-            self.mcu_stepper.reset_step_clock(mcu_time)
-        if (self.mcu_enable is not None
-            and self.mcu_enable.get_last_setting() != enable):
-            mcu_time = self.mcu_enable.print_to_mcu_time(move_time)
-            self.mcu_enable.set_digital(mcu_time, enable)
-        self.need_motor_enable = not enable
     def enable_endstop_checking(self, move_time, step_time):
         mcu_time = self.mcu_endstop.print_to_mcu_time(move_time)
         self.mcu_endstop.home_start(mcu_time, step_time)