endstop_phase: Add support for an ENDSTOP_PHASE_CALIBRATE command

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

config/example-extras.cfg

@@ -326,7 +326,8 @@
 # config section with an "endstop_phase" prefix followed by the name
 # of the corresponding stepper config section (for example,
 # "[endstop_phase stepper_z]"). This feature can improve the accuracy
-# of endstop switches.
+# of endstop switches. Add a bare "[endstop_phase]" declaration to
+# enable the ENDSTOP_PHASE_CALIBRATE command.
 #[endstop_phase stepper_z]
 #phases:
 #   This specifies the number of phases of the given stepper motor

docs/G-Codes.md

@@ -221,6 +221,17 @@ is enabled:
 - `DUMP_TMC STEPPER=<name>`: This command will read the TMC2130 driver
   registers and report their values.
 
+## Endstop adjustments by stepper phase
+
+The following commands are available when an "endstop_phase" config
+section is enabled:
+- `ENDSTOP_PHASE_CALIBRATE [STEPPER=<config_name>]`: If no STEPPER
+  parameter is provided then this command will reports statistics on
+  endstop stepper phases during past homing operations. When a STEPPER
+  parameter is provided it arranges for the given endstop phase
+  setting to be written to the config file (in conjunction with the
+  SAVE_CONFIG command).
+
 ## Force movement
 
 The following commands are available when the "force_move" config

klippy/extras/endstop_phase.py

@@ -43,9 +43,11 @@ class EndstopPhase:
                                " stepper phase adjustment" % (self.name,))
         if self.printer.get_start_args().get('debugoutput') is not None:
             self.endstop_accuracy = self.phases
+        self.phase_history = [0] * self.phases
         # Register event handler
         self.printer.register_event_handler(
             "homing:homed_rails", self.handle_homed_rails)
+        self.printer.try_load_module(config, "endstop_phase")
     def align_endstop(self, pos):
         if not self.endstop_align_zero or self.endstop_phase is None:
             return pos
@@ -66,6 +68,7 @@ class EndstopPhase:
                 raise homing.EndstopError(msg)
         else:
             phase = stepper.get_mcu_position() % self.phases
+        self.phase_history[phase] += 1
         if self.endstop_phase is None:
             logging.info("Setting %s endstop phase to %d", self.name, phase)
             self.endstop_phase = phase
@@ -91,5 +94,98 @@ class EndstopPhase:
             rail.set_commanded_position(pos)
             return True
 
+class EndstopPhases:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.gcode = self.printer.lookup_object('gcode')
+        self.gcode.register_command("ENDSTOP_PHASE_CALIBRATE",
+                                    self.cmd_ENDSTOP_PHASE_CALIBRATE,
+                                    desc=self.cmd_ENDSTOP_PHASE_CALIBRATE_help)
+        self.tracking = {}
+        # Register event handler
+        self.printer.register_event_handler(
+            "homing:homed_rails", self.handle_homed_rails)
+    def lookup_rail(self, stepper, stepper_name):
+        mod_name = "endstop_phase %s" % (stepper_name,)
+        m = self.printer.lookup_object(mod_name, None)
+        if m is not None:
+            return (None, m.phase_history)
+        for driver in TRINAMIC_DRIVERS:
+            mod_name = "%s %s" % (driver, stepper_name)
+            m = self.printer.lookup_object(mod_name, None)
+            if m is not None:
+                return (m.get_phase, [0] * (m.get_microsteps() * 4))
+        return None
+    def update_rail(self, info, stepper):
+        if info is None:
+            return
+        get_phase, phase_history = info
+        if get_phase is None:
+            return
+        try:
+            phase = get_phase()
+        except:
+            logging.exception("Error in EndstopPhases get_phase")
+            return
+        phase_history[phase] += 1
+    def handle_homed_rails(self, homing_state, rails):
+        for rail in rails:
+            stepper = rail.get_steppers()[0]
+            stepper_name = stepper.get_name()
+            if stepper_name not in self.tracking:
+                info = self.lookup_rail(stepper, stepper_name)
+                self.tracking[stepper_name] = info
+            self.update_rail(self.tracking[stepper_name], stepper)
+    cmd_ENDSTOP_PHASE_CALIBRATE_help = "Calibrate stepper phase"
+    def cmd_ENDSTOP_PHASE_CALIBRATE(self, params):
+        stepper_name = self.gcode.get_str('STEPPER', params, None)
+        if stepper_name is None:
+            self.report_stats()
+            return
+        info = self.tracking.get(stepper_name)
+        if info is None:
+            raise self.gcode.error("Stats not available for stepper %s" % (
+                stepper_name,))
+        endstop_phase = self.generate_stats(stepper_name, info)
+        configfile = self.printer.lookup_object('configfile')
+        section = 'endstop_phase %s' % stepper_name
+        configfile.remove_section(section)
+        configfile.set(section, "endstop_phase", endstop_phase)
+        self.gcode.respond_info(
+            "The SAVE_CONFIG command will update the printer config\n"
+            "file with these parameters and restart the printer.")
+    def generate_stats(self, stepper_name, info):
+        get_phase, phase_history = info
+        wph = phase_history + phase_history
+        count = sum(phase_history)
+        phases = len(phase_history)
+        half_phases = phases // 2
+        res = []
+        for i in range(phases):
+            phase = i + half_phases
+            cost = sum([wph[j] * abs(j-phase) for j in range(i, i+phases)])
+            res.append((cost, phase))
+        res.sort()
+        best = res[0][1]
+        found = [j for j in range(best - half_phases, best + half_phases)
+                 if wph[j]]
+        best_phase = best % phases
+        lo, hi = found[0] % phases, found[-1] % phases
+        self.gcode.respond_info("%s: endstop_phase=%d (range %d to %d)" % (
+            stepper_name, best_phase, lo, hi))
+        return best_phase
+    def report_stats(self):
+        if not self.tracking:
+            self.gcode.respond_info(
+                "No steppers found. (Be sure to home at least once.)")
+            return
+        for stepper_name, info in sorted(self.tracking.items()):
+            if info is None:
+                continue
+            self.generate_stats(stepper_name, info)
+
 def load_config_prefix(config):
     return EndstopPhase(config)
+
+def load_config(config):
+    return EndstopPhases(config)