extruder_stepper: Support changing synced extruder on the fly (#2824)

Signed-off-by: Christopher Meredith <chmeredith@gmail.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/klippy/extras/extruder_stepper.py b/klippy/extras/extruder_stepper.py
index f6d0e9ea..58f16375 100644
--- a/klippy/extras/extruder_stepper.py
+++ b/klippy/extras/extruder_stepper.py
@@ -9,17 +9,37 @@ import stepper
 class ExtruderStepper:
     def __init__(self, config):
         self.printer = config.get_printer()
+        stepper_name = config.get_name().split()[1]
         self.extruder_name = config.get('extruder', 'extruder')
         self.stepper = stepper.PrinterStepper(config)
         self.stepper.set_max_jerk(9999999.9, 9999999.9)
         self.stepper.setup_itersolve('extruder_stepper_alloc')
         self.printer.register_event_handler("klippy:connect",
                                             self.handle_connect)
+        gcode = self.printer.lookup_object('gcode')
+        gcode.register_mux_command("SYNC_STEPPER_TO_EXTRUDER", "STEPPER",
+                                   stepper_name,
+                                   self.cmd_SYNC_STEPPER_TO_EXTRUDER,
+                                   desc=self.cmd_SYNC_STEPPER_TO_EXTRUDER_help)
     def handle_connect(self):
         extruder = self.printer.lookup_object(self.extruder_name)
         self.stepper.set_trapq(extruder.get_trapq())
         toolhead = self.printer.lookup_object('toolhead')
         toolhead.register_step_generator(self.stepper.generate_steps)
+    cmd_SYNC_STEPPER_TO_EXTRUDER_help = "Set extruder stepper"
+    def cmd_SYNC_STEPPER_TO_EXTRUDER(self, gcmd):
+        gcode = self.printer.lookup_object('gcode')
+        self.extruder_name = gcmd.get('EXTRUDER', None)
+        extruder = self.printer.lookup_object(self.extruder_name, None)
+        if extruder is not None:
+            epos = extruder.stepper.get_commanded_position()
+            self.stepper.set_position([epos, 0., 0.])
+            self.stepper.set_trapq(extruder.get_trapq())
+            gcode.respond_info("Extruder stepper now syncing with '%s'"
+                                       % (self.extruder_name))
+        else:
+            raise gcmd.error("'%s' is not a valid extruder."
+                                       % (self.extruder_name))
 
 def load_config_prefix(config):
     return ExtruderStepper(config)