bltouch: Add initial support for a bltouch "extras" module

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

2 files changed, 98 insertions, 6 deletions

diff --git a/klippy/extras/bltouch.py b/klippy/extras/bltouch.py
new file mode 100644
index 00000000..c3ce14db
--- /dev/null
+++ b/klippy/extras/bltouch.py
@@ -0,0 +1,93 @@
+# BLTouch support
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import homing, probe
+
+SIGNAL_PERIOD = 0.025600
+PIN_MOVE_TIME = 8 * SIGNAL_PERIOD
+MIN_CMD_TIME = 4 * SIGNAL_PERIOD
+
+TEST_TIME = 5 * 60.
+ENDSTOP_SAMPLE_TIME = .000015
+ENDSTOP_SAMPLE_COUNT = 4
+
+CMD_PIN_DOWN = 0.000700
+CMD_PIN_UP = 0.001500
+CMD_SELF_TEST = 0.001800
+CMD_RESET = 0.002200
+CMD_TOUCH_MODE = 0.001200
+
+# BLTouch "endstop" wrapper
+class BLTouchEndstopWrapper:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.next_test_time = 0.
+        self.position_endstop = config.getfloat('z_offset')
+        # Create a pwm object to handle the control pin
+        ppins = self.printer.lookup_object('pins')
+        self.mcu_pwm = ppins.setup_pin('pwm', config.get('control_pin'))
+        self.mcu_pwm.setup_max_duration(0.)
+        self.mcu_pwm.setup_cycle_time(SIGNAL_PERIOD)
+        # Create an "endstop" object to handle the sensor pin
+        pin = config.get('sensor_pin')
+        pin_params = ppins.lookup_pin(pin, can_invert=True, can_pullup=True)
+        mcu = pin_params['chip']
+        mcu.register_config_callback(self._build_config)
+        self.mcu_endstop = mcu.setup_pin('endstop', pin_params)
+        # Wrappers
+        self.get_mcu = self.mcu_endstop.get_mcu
+        self.add_stepper = self.mcu_endstop.add_stepper
+        self.get_steppers = self.mcu_endstop.get_steppers
+        self.home_start = self.mcu_endstop.home_start
+        self.home_wait = self.mcu_endstop.home_wait
+        self.query_endstop = self.mcu_endstop.query_endstop
+        self.query_endstop_wait = self.mcu_endstop.query_endstop_wait
+        self.TimeoutError = self.mcu_endstop.TimeoutError
+    def _build_config(self):
+        kin = self.printer.lookup_object('toolhead').get_kinematics()
+        for stepper in kin.get_steppers('Z'):
+            stepper.add_to_endstop(self)
+    def send_cmd(self, print_time, cmd):
+        self.mcu_pwm.set_pwm(print_time, cmd / SIGNAL_PERIOD)
+    def test_sensor(self):
+        toolhead = self.printer.lookup_object('toolhead')
+        print_time = toolhead.get_last_move_time()
+        if print_time < self.next_test_time:
+            self.next_test_time = print_time + TEST_TIME
+            return
+        self.send_cmd(print_time, CMD_RESET)
+        home_time = print_time + PIN_MOVE_TIME
+        self.send_cmd(home_time, CMD_TOUCH_MODE)
+        self.send_cmd(home_time + MIN_CMD_TIME, 0.)
+        self.mcu_endstop.home_start(
+            home_time, ENDSTOP_SAMPLE_TIME, ENDSTOP_SAMPLE_COUNT, .001)
+        try:
+            self.mcu_endstop.home_wait(home_time + MIN_CMD_TIME)
+        except self.mcu_endstop.TimeoutError as e:
+            raise homing.EndstopError("BLTouch sensor test failed")
+        self.next_test_time = home_time + TEST_TIME
+        toolhead.reset_print_time(home_time + 2. * MIN_CMD_TIME)
+    def home_prepare(self):
+        self.test_sensor()
+        toolhead = self.printer.lookup_object('toolhead')
+        print_time = toolhead.get_last_move_time()
+        self.send_cmd(print_time, CMD_PIN_DOWN)
+        self.send_cmd(print_time + PIN_MOVE_TIME, CMD_TOUCH_MODE)
+        toolhead.dwell(PIN_MOVE_TIME + MIN_CMD_TIME)
+        self.mcu_endstop.home_prepare()
+    def home_finalize(self):
+        toolhead = self.printer.lookup_object('toolhead')
+        print_time = toolhead.get_last_move_time()
+        self.send_cmd(print_time, CMD_RESET)
+        self.send_cmd(print_time + PIN_MOVE_TIME, 0.)
+        toolhead.dwell(PIN_MOVE_TIME + MIN_CMD_TIME)
+        self.mcu_endstop.home_finalize()
+    def get_position_endstop(self):
+        return self.position_endstop
+
+def load_config(config):
+    blt = BLTouchEndstopWrapper(config)
+    config.get_printer().add_object('probe', probe.PrinterProbe(config, blt))
+    return blt
diff --git a/klippy/extras/probe.py b/klippy/extras/probe.py
index 5a5096cf..24223cfb 100644
--- a/klippy/extras/probe.py
+++ b/klippy/extras/probe.py
@@ -13,8 +13,9 @@ the Z axis minimum position so the probe can travel further
 """
 
 class PrinterProbe:
-    def __init__(self, config):
+    def __init__(self, config, mcu_probe):
         self.printer = config.get_printer()
+        self.mcu_probe = mcu_probe
         self.speed = config.getfloat('speed', 5.0)
         self.x_offset = config.getfloat('x_offset', 0.)
         self.y_offset = config.getfloat('y_offset', 0.)
@@ -26,10 +27,8 @@ class PrinterProbe:
         else:
             pconfig = config.getsection('printer')
             self.z_position = pconfig.getfloat('minimum_z_position', 0.)
-        # Create mcu_probe object and register z_virtual_endstop pin
-        self.mcu_probe = ProbeEndstopWrapper(config)
-        ppins = self.printer.lookup_object('pins')
-        ppins.register_chip('probe', self)
+        # Register z_virtual_endstop pin
+        self.printer.lookup_object('pins').register_chip('probe', self)
         # Register PROBE/QUERY_PROBE commands
         self.gcode = self.printer.lookup_object('gcode')
         self.gcode.register_command(
@@ -239,4 +238,4 @@ class ProbePointsHelper:
             self.finalize_callback(self.probe_offsets, self.results)
 
 def load_config(config):
-    return PrinterProbe(config)
+    return PrinterProbe(config, ProbeEndstopWrapper(config))