diff options
Diffstat (limited to 'klippy/extras/pwm_cycle_time.py')
| -rw-r--r-- | klippy/extras/pwm_cycle_time.py | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/klippy/extras/pwm_cycle_time.py b/klippy/extras/pwm_cycle_time.py new file mode 100644 index 00000000..cebbec75 --- /dev/null +++ b/klippy/extras/pwm_cycle_time.py @@ -0,0 +1,123 @@ +# Handle pwm output pins with variable frequency +# +# Copyright (C) 2017-2023 Kevin O'Connor <kevin@koconnor.net> +# +# This file may be distributed under the terms of the GNU GPLv3 license. + +PIN_MIN_TIME = 0.100 +MAX_SCHEDULE_TIME = 5.0 + +class MCU_pwm_cycle: + def __init__(self, pin_params, cycle_time, start_value, shutdown_value): + self._mcu = pin_params['chip'] + self._cycle_time = cycle_time + self._oid = None + self._mcu.register_config_callback(self._build_config) + self._pin = pin_params['pin'] + self._invert = pin_params['invert'] + if self._invert: + start_value = 1. - start_value + shutdown_value = 1. - shutdown_value + self._start_value = max(0., min(1., start_value)) + self._shutdown_value = max(0., min(1., shutdown_value)) + self._last_clock = self._cycle_ticks = 0 + self._set_cmd = self._set_cycle_ticks = None + def _build_config(self): + cmd_queue = self._mcu.alloc_command_queue() + curtime = self._mcu.get_printer().get_reactor().monotonic() + printtime = self._mcu.estimated_print_time(curtime) + self._last_clock = self._mcu.print_time_to_clock(printtime + 0.200) + cycle_ticks = self._mcu.seconds_to_clock(self._cycle_time) + if self._shutdown_value not in [0., 1.]: + raise self._mcu.get_printer().config_error( + "shutdown value must be 0.0 or 1.0 on soft pwm") + if cycle_ticks >= 1<<31: + raise self._mcu.get_printer().config_error( + "PWM pin cycle time too large") + self._mcu.request_move_queue_slot() + self._oid = self._mcu.create_oid() + self._mcu.add_config_cmd( + "config_digital_out oid=%d pin=%s value=%d" + " default_value=%d max_duration=%d" + % (self._oid, self._pin, self._start_value >= 1.0, + self._shutdown_value >= 0.5, 0)) + self._mcu.add_config_cmd( + "set_digital_out_pwm_cycle oid=%d cycle_ticks=%d" + % (self._oid, cycle_ticks)) + self._cycle_ticks = cycle_ticks + svalue = int(self._start_value * cycle_ticks + 0.5) + self._mcu.add_config_cmd( + "queue_digital_out oid=%d clock=%d on_ticks=%d" + % (self._oid, self._last_clock, svalue), is_init=True) + self._set_cmd = self._mcu.lookup_command( + "queue_digital_out oid=%c clock=%u on_ticks=%u", cq=cmd_queue) + self._set_cycle_ticks = self._mcu.lookup_command( + "set_digital_out_pwm_cycle oid=%c cycle_ticks=%u", cq=cmd_queue) + def set_pwm_cycle(self, print_time, value, cycle_time): + clock = self._mcu.print_time_to_clock(print_time) + minclock = self._last_clock + # Send updated cycle_time if necessary + cycle_ticks = self._mcu.seconds_to_clock(cycle_time) + if cycle_ticks != self._cycle_ticks: + if cycle_ticks >= 1<<31: + raise self._mcu.get_printer().command_error( + "PWM cycle time too large") + self._set_cycle_ticks.send([self._oid, cycle_ticks], + minclock=minclock, reqclock=clock) + self._cycle_ticks = cycle_ticks + # Send pwm update + if self._invert: + value = 1. - value + v = int(max(0., min(1., value)) * float(self._cycle_ticks) + 0.5) + self._set_cmd.send([self._oid, clock, v], + minclock=self._last_clock, reqclock=clock) + self._last_clock = clock + +class PrinterOutputPWMCycle: + def __init__(self, config): + self.printer = config.get_printer() + self.last_print_time = 0. + cycle_time = config.getfloat('cycle_time', 0.100, above=0., + maxval=MAX_SCHEDULE_TIME) + self.last_cycle_time = self.default_cycle_time = cycle_time + # Determine start and shutdown values + self.scale = config.getfloat('scale', 1., above=0.) + self.last_value = config.getfloat( + 'value', 0., minval=0., maxval=self.scale) / self.scale + self.shutdown_value = config.getfloat( + 'shutdown_value', 0., minval=0., maxval=self.scale) / self.scale + # Create pwm pin object + ppins = self.printer.lookup_object('pins') + pin_params = ppins.lookup_pin(config.get('pin'), can_invert=True) + self.mcu_pin = MCU_pwm_cycle(pin_params, cycle_time, + self.last_value, self.shutdown_value) + # Register commands + pin_name = config.get_name().split()[1] + gcode = self.printer.lookup_object('gcode') + gcode.register_mux_command("SET_PIN", "PIN", pin_name, + self.cmd_SET_PIN, + desc=self.cmd_SET_PIN_help) + def get_status(self, eventtime): + return {'value': self.last_value} + def _set_pin(self, print_time, value, cycle_time): + if value == self.last_value and cycle_time == self.last_cycle_time: + return + print_time = max(print_time, self.last_print_time + PIN_MIN_TIME) + self.mcu_pin.set_pwm_cycle(print_time, value, cycle_time) + self.last_value = value + self.last_cycle_time = cycle_time + self.last_print_time = print_time + cmd_SET_PIN_help = "Set the value of an output pin" + def cmd_SET_PIN(self, gcmd): + # Read requested value + value = gcmd.get_float('VALUE', minval=0., maxval=self.scale) + value /= self.scale + cycle_time = gcmd.get_float('CYCLE_TIME', self.default_cycle_time, + above=0., maxval=MAX_SCHEDULE_TIME) + # Obtain print_time and apply requested settings + toolhead = self.printer.lookup_object('toolhead') + toolhead.register_lookahead_callback( + lambda print_time: self._set_pin(print_time, value, cycle_time)) + +def load_config_prefix(config): + return PrinterOutputPWMCycle(config) |