filament_switch_sensor: initial implementation of switch based filament runout/insert sensor

This implementation includes a BaseSensor class that all underlying sensor implementations should subclass.

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

klippy/extras/filament_switch_sensor.py

@@ -0,0 +1,124 @@
+# Generic Filament Sensor Module
+#
+# Copyright (C) 2019  Eric Callahan <arksine.code@gmail.com>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import logging
+
+class BaseSensor(object):
+    def __init__(self, config):
+        self.name = config.get_name().split()[1]
+        self.printer = config.get_printer()
+        self.gcode = self.printer.lookup_object('gcode')
+        self.runout_gcode = config.get('runout_gcode', None)
+        self.insert_gcode = config.get('insert_gcode', None)
+        self.runout_pause = config.getboolean('pause_on_runout', True)
+        if self.runout_pause:
+            if self.runout_gcode is None:
+                self.runout_gcode = "PAUSE"
+            else:
+                self.runout_gcode = "PAUSE\n" + self.runout_gcode
+        self.runout_enabled = False
+        self.insert_enabled = self.insert_gcode is not None
+        self.event_running = False
+        self.print_status = "idle"
+        self.printer.register_event_handler(
+            "idle_timeout:idle",
+            (lambda e, s=self, st="idle": s._update_print_status(e, st)))
+        self.printer.register_event_handler(
+            "idle_timeout:ready",
+            (lambda e, s=self, st="ready": s._update_print_status(e, st)))
+        self.printer.register_event_handler(
+            "idle_timeout:printing",
+            (lambda e, s=self, st="printing": s._update_print_status(e, st)))
+    def _handle_ready(self):
+        self.toolhead = self.printer.lookup_object('toolhead')
+    def _update_print_status(self, eventtime, status):
+        if status == "printing":
+            runout_en = self.runout_gcode is not None
+            self.set_enable(runout_en, False)
+        else:
+            insert_en = self.insert_gcode is not None
+            self.set_enable(False, insert_en)
+    def _runout_event_handler(self, eventtime):
+        if self.event_running:
+            return
+        self.event_running = True
+        # Pausing from inside an event requires that the pause portion
+        # of pause_resume execute immediately.
+        pause_resume = self.printer.lookup_object('pause_resume', None)
+        if self.runout_pause and pause_resume is not None:
+            pause_resume.send_pause_command()
+        self._exec_gcode(self.runout_gcode)
+        self.event_running = False
+    def _insert_event_handler(self, eventtime):
+        if self.event_running:
+            return
+        self.event_running = True
+        self._exec_gcode(self.insert_gcode)
+        self.event_running = False
+    def _exec_gcode(self, script):
+        try:
+            self.gcode.run_script(script)
+        except Exception:
+            logging.exception("Script running error")
+    def set_enable(self, runout, insert):
+        if runout and insert:
+            # both cannot be enabled
+            insert = False
+        self.runout_enabled = runout
+        self.insert_enabled = insert
+    cmd_QUERY_FILAMENT_SENSOR_help = "Query the status of the Filament Sensor"
+    def cmd_QUERY_FILAMENT_SENSOR(self, params):
+        raise NotImplementedError(
+            "Sensor must implement cmd_QUERY_FILAMENT_SENSOR")
+
+class SwitchSensor(BaseSensor):
+    def __init__(self, config):
+        super(SwitchSensor, self).__init__(config)
+        self.reactor = self.printer.get_reactor()
+        self.buttons = self.printer.try_load_module(config, 'buttons')
+        switch_pin = config.get('switch_pin')
+        self.buttons.register_buttons([switch_pin], self._button_handler)
+        self.event_delay = config.getfloat('event_delay', 3., above=0.)
+        self.start_time = self.reactor.NEVER
+        self.last_button_state = False
+        self.last_cb_event_time = 0.
+        self.gcode.register_mux_command(
+            "QUERY_FILAMENT_SENSOR", "SENSOR", self.name,
+            self.cmd_QUERY_FILAMENT_SENSOR,
+            desc=self.cmd_QUERY_FILAMENT_SENSOR_help)
+        self.printer.register_event_handler("klippy:ready", self._handle_ready)
+    def _handle_ready(self):
+        super(SwitchSensor, self)._handle_ready()
+        self.start_time = self.reactor.monotonic() + 2.
+    def _button_handler(self, eventtime, state):
+        if eventtime < self.start_time or state == self.last_button_state:
+            self.last_button_state = state
+            return
+        if state:
+            # button pushed, check if insert callback should happen
+            if (self.insert_enabled and
+                    (eventtime - self.last_cb_event_time) > self.event_delay):
+                self.last_cb_event_time = eventtime
+                logging.info(
+                    "switch_sensor: insert event detected, Time %.2f",
+                    eventtime)
+                self.reactor.register_callback(self._insert_event_handler)
+        elif (self.runout_enabled and
+                (eventtime - self.last_cb_event_time) > self.event_delay):
+            # Filament runout detected
+            self.last_cb_event_time = eventtime
+            logging.info(
+                "switch_sensor: runout event detected, Time %.2f", eventtime)
+            self.reactor.register_callback(self._runout_event_handler)
+        self.last_button_state = state
+    def cmd_QUERY_FILAMENT_SENSOR(self, params):
+        if self.last_button_state:
+            msg = "Switch Sensor: filament detected"
+        else:
+            msg = "Switch Sensor: filament not detected"
+        self.gcode.respond_info(msg)
+
+def load_config_prefix(config):
+    return SwitchSensor(config)