# BLTouch support
#
# Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import math, logging
import homing, probe
SIGNAL_PERIOD = 0.020
MIN_CMD_TIME = 5 * SIGNAL_PERIOD
TEST_TIME = 5 * 60.
RETRY_RESET_TIME = 1.
ENDSTOP_REST_TIME = .001
ENDSTOP_SAMPLE_TIME = .000015
ENDSTOP_SAMPLE_COUNT = 4
Commands = {
None: 0.0, 'pin_down': 0.000650, 'touch_mode': 0.001165,
'pin_up': 0.001475, 'self_test': 0.001780, 'reset': 0.002190,
}
# BLTouch "endstop" wrapper
class BLTouchEndstopWrapper:
def __init__(self, config):
self.printer = config.get_printer()
self.printer.register_event_handler("klippy:connect",
self.handle_connect)
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)
self.next_cmd_time = 0.
# 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)
# Setup for sensor test
self.next_test_time = 0.
self.pin_up_not_triggered = config.getboolean(
'pin_up_reports_not_triggered', True)
self.pin_up_touch_triggered = config.getboolean(
'pin_up_touch_mode_reports_triggered', True)
self.start_mcu_pos = []
# Calculate pin move time
pmt = max(config.getfloat('pin_move_time', 0.675), MIN_CMD_TIME)
self.pin_move_time = math.ceil(pmt / SIGNAL_PERIOD) * SIGNAL_PERIOD
# 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_wait = self.mcu_endstop.home_wait
self.query_endstop = self.mcu_endstop.query_endstop
self.TimeoutError = self.mcu_endstop.TimeoutError
# Register BLTOUCH_DEBUG command
self.gcode = self.printer.lookup_object('gcode')
self.gcode.register_command("BLTOUCH_DEBUG", self.cmd_BLTOUCH_DEBUG,
desc=self.cmd_BLTOUCH_DEBUG_help)
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 handle_connect(self):
try:
self.raise_probe()
except homing.CommandError as e:
logging.warning("BLTouch raise probe error: %s", str(e))
def sync_mcu_print_time(self):
curtime = self.printer.get_reactor().monotonic()
est_time = self.mcu_pwm.get_mcu().estimated_print_time(curtime)
self.next_cmd_time = max(self.next_cmd_time, est_time + MIN_CMD_TIME)
def sync_print_time(self):
toolhead = self.printer.lookup_object('toolhead')
print_time = toolhead.get_last_move_time()
if self.next_cmd_time > print_time:
toolhead.dwell(self.next_cmd_time - print_time)
else:
self.next_cmd_time = print_time
def send_cmd(self, cmd, duration=MIN_CMD_TIME):
self.mcu_pwm.set_pwm(self.next_cmd_time, Commands[cmd] / SIGNAL_PERIOD)
# Translate duration to ticks to avoid any secondary mcu clock skew
mcu = self.mcu_pwm.get_mcu()
cmd_clock = mcu.print_time_to_clock(self.next_cmd_time)
cmd_clock += mcu.seconds_to_clock(max(duration, MIN_CMD_TIME))
self.next_cmd_time = mcu.clock_to_print_time(cmd_clock)
return self.next_cmd_time
def verify_state(self, check_start_time, check_end_time, triggered, msg):
# Perform endstop check to verify bltouch reports desired state
prev_positions = [s.get_commanded_position()
for s in self.mcu_endstop.get_steppers()]
self.mcu_endstop.home_start(check_start_time, ENDSTOP_SAMPLE_TIME,
ENDSTOP_SAMPLE_COUNT, ENDSTOP_REST_TIME,
triggered=triggered)
try:
self.mcu_endstop.home_wait(check_end_time)
except self.mcu_endstop.TimeoutError as e:
raise homing.EndstopError("BLTouch failed to %s" % (msg,))
for s, pos in zip(self.mcu_endstop.get_steppers(), prev_positions):
s.set_commanded_position(pos)
def raise_probe(self):
for retry in range(3):
self.sync_mcu_print_time()
if retry or not self.pin_up_not_triggered:
self.send_cmd('reset')
check_start_time = self.send_cmd('pin_up',
duration=self.pin_move_time)
check_end_time = self.send_cmd(None)
if self.pin_up_not_triggered:
try:
self.verify_state(check_start_time, check_end_time,
False, "raise probe")
except homing.CommandError as e:
if retry >= 2:
raise
msg = "Failed to verify BLTouch probe is raised; retrying."
self.gcode.respond_info(msg)
self.next_cmd_time += RETRY_RESET_TIME
continue
break
def test_sensor(self):
if not self.pin_up_touch_triggered:
# Nothing to test
return
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
# Raise the bltouch probe and test if probe is raised
self.sync_print_time()
check_start_time = self.send_cmd('reset', duration=self.pin_move_time)
check_end_time = self.send_cmd('touch_mode')
self.send_cmd(None)
self.verify_state(check_start_time, check_end_time, True,
"verify sensor state")
# Test was successful
self.next_test_time = check_end_time + TEST_TIME
self.sync_print_time()
def home_prepare(self):
self.test_sensor()
self.sync_print_time()
self.send_cmd('pin_down', duration=self.pin_move_time - MIN_CMD_TIME)
self.send_cmd(None)
self.sync_print_time()
self.mcu_endstop.home_prepare()
self.start_mcu_pos = [(s, s.get_mcu_position())
for s in self.mcu_endstop.get_steppers()]
def home_finalize(self):
self.raise_probe()
self.sync_print_time()
# Verify the probe actually deployed during the attempt
for s, mcu_pos in self.start_mcu_pos:
if s.get_mcu_position() == mcu_pos:
raise homing.EndstopError("BLTouch failed to deploy")
self.mcu_endstop.home_finalize()
def home_start(self, print_time, sample_time, sample_count, rest_time,
notify=None):
rest_time = min(rest_time, ENDSTOP_REST_TIME)
self.mcu_endstop.home_start(print_time, sample_time, sample_count,
rest_time, notify=notify)
def get_position_endstop(self):
return self.position_endstop
cmd_BLTOUCH_DEBUG_help = "Send a command to the bltouch for debugging"
def cmd_BLTOUCH_DEBUG(self, params):
cmd = self.gcode.get_str('COMMAND', params, None)
if cmd is None or cmd not in Commands:
self.gcode.respond_info("BLTouch commands: %s" % (
", ".join(sorted([c for c in Commands if c is not None]))))
return
self.gcode.respond_info("Sending BLTOUCH_DEBUG COMMAND=%s" % (cmd,))
self.sync_print_time()
self.send_cmd(cmd, duration=self.pin_move_time)
self.send_cmd(None)
self.sync_print_time()
def load_config(config):
blt = BLTouchEndstopWrapper(config)
config.get_printer().add_object('probe', probe.PrinterProbe(config, blt))
return blt