klipper/klippy/homing.py

# Code for state tracking during homing operations
#
# Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.

import logging

class Homing:
    def __init__(self, toolhead, changed_axes):
        self.toolhead = toolhead
        self.changed_axes = changed_axes

        self.states = []
        self.endstops = []
    def plan_home(self, forcepos, movepos, steppers, speed):
        self.states.append((self.do_home, (forcepos, movepos, steppers, speed)))
        self.states.append((self.do_wait_endstop, ()))
    def plan_move(self, newpos, speed):
        self.states.append((self.do_move, (newpos, speed)))
    def plan_axes_update(self, callback):
        self.states.append((callback, (self.changed_axes,)))
    def check_busy(self, eventtime):
        while self.states:
            first = self.states[0]
            ret = first[0](*first[1])
            if ret:
                return True
            self.states.pop(0)
        return False

    def fill_coord(self, coord):
        # Fill in any None entries in 'coord' with current toolhead position
        thcoord = self.toolhead.get_position()
        coord = list(coord)
        for i in range(len(coord)):
            if coord[i] is None:
                coord[i] = thcoord[i]
        return coord
    def do_move(self, newpos, speed):
        # Issue a move command
        self.toolhead.move(self.fill_coord(newpos), speed)
        return False
    def do_home(self, forcepos, movepos, steppers, speed):
        # Alter kinematics class to think printer is at forcepos
        self.toolhead.set_position(self.fill_coord(forcepos))
        # Start homing and issue move
        print_time = self.toolhead.get_last_move_time()
        for s in steppers:
            hz = speed * s.inv_step_dist
            es = s.enable_endstop_checking(print_time, hz)
            self.endstops.append(es)
        self.toolhead.move(self.fill_coord(movepos), speed)
        self.toolhead.reset_print_time()
        for es in self.endstops:
            es.home_finalize()
        return False
    def do_wait_endstop(self):
        # Check if endstops have triggered
        for es in self.endstops:
            if es.is_homing():
                return True
        # Finished
        del self.endstops[:]
        return False