homing_override: Allow moves prior to homing an axis

Add support for disabling homing checks via the homing_override
mechanism.  This may be useful to move an axis prior to homing it.

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

config/example-extras.cfg

@@ -294,6 +294,14 @@
 #   contained in this list of commands then it will invoke the normal
 #   homing procedure for the printer. The commands listed here must
 #   home all axes. This parameter must be provided.
+#set_position_x:
+#set_position_y:
+#set_position_z:
+#   If specified, the position to set the printer to (in mm, relative
+#   to the coordinate system specified in the config file) prior to
+#   running the above g-code commands. Setting this may be useful if
+#   an axis must move prior to invoking the normal G28 mechanism for
+#   that axis. The default is to not force a position for the axis.
 
 
 # Replicape support - see the generic-replicape.cfg file for further

klippy/cartesian.py

@@ -32,14 +32,16 @@ class CartKinematics:
         return list(self.steppers)
     def get_position(self):
         return [s.mcu_stepper.get_commanded_position() for s in self.steppers]
-    def set_position(self, newpos):
+    def set_position(self, newpos, homing_axes):
         for i in StepList:
-            self.steppers[i].set_position(newpos[i])
+            s = self.steppers[i]
+            s.set_position(newpos[i])
+            if i in homing_axes:
+                self.limits[i] = (s.position_min, s.position_max)
     def home(self, homing_state):
         # Each axis is homed independently and in order
         for axis in homing_state.get_axes():
             s = self.steppers[axis]
-            self.limits[axis] = (s.position_min, s.position_max)
             # Determine moves
             if s.homing_positive_dir:
                 pos = s.position_endstop - 1.5*(

klippy/corexy.py

@@ -40,15 +40,17 @@ class CoreXYKinematics:
     def get_position(self):
         pos = [s.mcu_stepper.get_commanded_position() for s in self.steppers]
         return [0.5 * (pos[0] + pos[1]), 0.5 * (pos[0] - pos[1]), pos[2]]
-    def set_position(self, newpos):
+    def set_position(self, newpos, homing_axes):
         pos = (newpos[0] + newpos[1], newpos[0] - newpos[1], newpos[2])
         for i in StepList:
-            self.steppers[i].set_position(pos[i])
+            s = self.steppers[i]
+            s.set_position(pos[i])
+            if i in homing_axes:
+                self.limits[i] = (s.position_min, s.position_max)
     def home(self, homing_state):
         # Each axis is homed independently and in order
         for axis in homing_state.get_axes():
             s = self.steppers[axis]
-            self.limits[axis] = (s.position_min, s.position_max)
             # Determine moves
             if s.homing_positive_dir:
                 pos = s.position_endstop - 1.5*(

klippy/delta.py

@@ -71,7 +71,7 @@ class DeltaKinematics:
             "Delta max build radius %.2fmm (moves slowed past %.2fmm and %.2fmm)"
             % (math.sqrt(self.max_xy2), math.sqrt(self.slow_xy2),
                math.sqrt(self.very_slow_xy2)))
-        self.set_position([0., 0., 0.])
+        self.set_position([0., 0., 0.], ())
     def get_steppers(self, flags=""):
         return list(self.steppers)
     def _cartesian_to_actuator(self, coord):
@@ -83,17 +83,18 @@ class DeltaKinematics:
     def get_position(self):
         spos = [s.mcu_stepper.get_commanded_position() for s in self.steppers]
         return self._actuator_to_cartesian(spos)
-    def set_position(self, newpos):
+    def set_position(self, newpos, homing_axes):
         pos = self._cartesian_to_actuator(newpos)
         for i in StepList:
             self.steppers[i].set_position(pos[i])
         self.limit_xy2 = -1.
+        if tuple(homing_axes) == StepList:
+            self.need_home = False
     def home(self, homing_state):
         # All axes are homed simultaneously
         homing_state.set_axes([0, 1, 2])
         endstops = [es for s in self.steppers for es in s.get_endstops()]
         s = self.steppers[0] # Assume homing speed same for all steppers
-        self.need_home = False
         # Initial homing
         homing_speed = min(s.homing_speed, self.max_z_velocity)
         homepos = [0., 0., self.max_z, None]

klippy/extras/homing_override.py

@@ -6,16 +6,29 @@
 
 class HomingOverride:
     def __init__(self, config):
-        printer = config.get_printer()
+        self.printer = config.get_printer()
+        self.start_pos = [config.getfloat('set_position_' + a, None)
+                          for a in 'xyz']
         self.script = config.get('gcode')
         self.in_script = False
-        self.gcode = printer.lookup_object('gcode')
+        self.gcode = self.printer.lookup_object('gcode')
         self.gcode.register_command("G28", self.cmd_G28)
     def cmd_G28(self, params):
         if self.in_script:
             # Was called recursively - invoke the real G28 command
             self.gcode.cmd_G28(params)
             return
+        # Calculate forced position (if configured)
+        toolhead = self.printer.lookup_object('toolhead')
+        pos = toolhead.get_position()
+        homing_axes = []
+        for axis, loc in enumerate(self.start_pos):
+            if loc is not None:
+                pos[axis] = loc
+                homing_axes.append(axis)
+        toolhead.set_position(pos, homing_axes=homing_axes)
+        self.gcode.reset_last_position()
+        # Perform homing
         try:
             self.in_script = True
             self.gcode.run_script(self.script)

klippy/homing.py

@@ -78,7 +78,9 @@ class Homing:
             raise EndstopError(error)
     def home(self, forcepos, movepos, endstops, speed, second_home=False):
         # Alter kinematics class to think printer is at forcepos
-        self.toolhead.set_position(self._fill_coord(forcepos))
+        homing_axes = [axis for axis in range(3) if forcepos[axis] is not None]
+        self.toolhead.set_position(
+            self._fill_coord(forcepos), homing_axes=homing_axes)
         # Add a CPU delay when homing a large axis
         if not second_home:
             est_move_d = sum([abs(forcepos[i]-movepos[i])

klippy/toolhead.py

@@ -312,10 +312,10 @@ class ToolHead:
     # Movement commands
     def get_position(self):
         return list(self.commanded_pos)
-    def set_position(self, newpos):
+    def set_position(self, newpos, homing_axes=()):
         self._flush_lookahead()
         self.commanded_pos[:] = newpos
-        self.kin.set_position(newpos)
+        self.kin.set_position(newpos, homing_axes)
     def move(self, newpos, speed):
         speed = min(speed, self.max_velocity)
         move = Move(self, self.commanded_pos, newpos, speed)