eap.cfg

# vim: tabstop=4 shiftwidth=4 expandtab

# Ejection Assisted Purge (EAP).
# Macros for Klipper.
# BRUSH
# PURGE
# PURGE_HOME
# PURGE_EJECT

[servo eap_servo]
pin: PG12
maximum_servo_angle: 180
minimum_pulse_width: 0.00050
maximum_pulse_width: 0.00250

[gcode_macro _PURGE_CFG]
# A central place for the configuration of all the macros in this file.
gcode:
#### Brushing.
# X,Y start position. A few mm past the right side of the brush.
variable_brush_start: 130, 305
# X stroke relative to the start. A few mm past the left of the brush.
variable_brush_stroke: -40
# X distance relative to the start position to clear away from the brush.
variable_brush_clear: 30
# Brushing speed in mm/s.
variable_brush_speed: 400
# How many times to brush.
variable_brush_count: 3
#
#### Purging.
# X, Y start position of the purging groove. A bit on right side of the end of
# the piston.
variable_groove_start: 50, 305
# Position relative to the start of the grove where to wait for cooling and
# ejection.
variable_cooling_pos: 15, -10
# Minimum cooling time in seconds. If less than the cooling time has elapsed,
# the next purge will wait for the end of the cooling period with the cooling
# fan atop.
variable_cooling_period: 15
# Default purging amount in mm³.
variable_volume: 140
# Default purging flow rate in mm³/s. Depends on the hotend, extruder, and
# viscocity of the plastic.
variable_flowrate: 20
# After a purge at a high flow rate, some pressure is left in the nozzle.
# A bit of retraction can even it out. Volume in mm³.
variable_retraction: 5.
# Retraction speed in mm/s.
variable_retraction_speed: 35
# Length of the groove relative (X) to the start.
variable_groove_len: 35
# Filament crosssection area in mm².
variable_fil_csa: 2.405 # 1.75mm filament.
# Groove crosssection area in mm².
variable_groove_csa: 5.3
#
#### Ejection.
# How long it takes to actuate the servo all the way.
# A MG90S servo is usually rated at 1.8ms/deg at 4.8V.
# Add some margin. For example 1.8ms*180 = 324ms -> 400ms.
variable_servo_dwell: 400
# How many actuations. Sometimes the pellet get stuck or missplaced, and
# another ejection fixes it.
variable_ejection_count: 2
#
#### General.
# Z limit. Below this height, refuses to do anything as a safety measure.
# The check can be turned off by passing ZCHECK=0 to the macros.
variable_z_min: 5
# Travel move speed in mm/s.
variable_travel_speed: 500

[gcode_macro BRUSH]
# This macro doesn't move in Z, only X and Y.
# Parameters:
#   CLEAR=1
#   ZHOP=-1
#   ZCHECK=1
gcode:
    # Clear away from the BRUSH at the end. Can be skipped to save a move.
    {% set clear = params.CLEAR|default(1)|int %}
    # Z hop if positive value.
    {% set zhop = params.ZHOP|default(-1)|float %}
    # Raise an error if z < z_min.
    {% set zcheck = params.ZCHECK|default(1)|int %}

    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}
    {% set tspeed = cfg.travel_speed * 60 %}
    {% set wspeed = cfg.brush_speed * 60 %}
    {% set sx = cfg.brush_start[0] %}
    {% set sy = cfg.brush_start[1] %}

    {% if "xyz" not in printer.toolhead.homed_axes %}
        { action_raise_error("Not homed") }
    {% elif zcheck and printer.toolhead.position.z < cfg.z_min %}
        { action_raise_error("Z too low") }
    {% else %}
        SAVE_GCODE_STATE NAME=BRUSH
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z{zhop} F{tspeed}
        {% endif %}
        G90 # absolute
        G0 X{sx} Y{sy} F{tspeed}
        {% for _ in range(0, cfg.brush_count) %}
            G0 X{sx + cfg.brush_stroke} F{wspeed}
            G0 X{sx} F{wspeed}
        {% endfor %}
        {% if clear == 1 %}
            G0 X{sx + cfg.brush_clear} F{tspeed}
        {% endif %}
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z{-zhop} F{tspeed}
        {% endif %}
        RESTORE_GCODE_STATE NAME=BRUSH
    {% endif %}

[gcode_macro PURGE]
# Eject the previous purge, then purge and plow through the brush.
# Parameters:
#   VOL=cfg.volume
#   FLOW=cfg.flowrate
#   RET=cfg.retraction
#   RETSPEED=cfg.retraction_speed
#   BRUSH_CLEAR=1
#   EJECT=1
#   ZHOP=-1
#   ZCHECK=1
#
# Maximum purge volume: abs(groove_len) * groove_csa.
# Example: 35mm * 5.3mm³ == 185mm³
variable_last_purge: 0.0
gcode:
    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}

    # The amount to purge in mm³.
    {% set vol = params.VOL|default(cfg.volume)|float %}
    # The purging flow rate in mm³/s.
    {% set flow = params.FLOW|default(cfg.flowrate)|float %}
    # The retraction amount in mm³.
    {% set retvol = params.RET|default(cfg.retraction)|float %}
    # The retraction in mm/s.
    {% set retspeed = params.RETSPEED|default(cfg.retraction_speed)|float %}

    # Clear away from the BRUSH at the end. Can be skipped to save a move.
    {% set brush_clear = params.BRUSH_CLEAR|default(1)|int %}
    # Call PURGE_HOME before purging.
    {% set eject  = params.EJECT|default(1)|int %}
    # Z hop if positive value.
    {% set zhop = params.ZHOP|default(-1)|float %}
    # Raise an error if z < z_min.
    {% set zcheck = params.ZCHECK|default(1)|int %}

    {% set tspeed = cfg.travel_speed * 60 %}
    {% set max_vol = (cfg.groove_len|abs * cfg.groove_csa) %}
    {% set sx = cfg.groove_start[0] %}
    {% set sy = cfg.groove_start[1] %}
    {% set initial_fan_speed = printer.fan.speed / printer.configfile.settings.fan.max_power %}

    {% if "xyz" not in printer.toolhead.homed_axes %}
        { action_raise_error("Not homed") }
    {% elif zcheck and printer.toolhead.position.z < cfg.z_min %}
        { action_raise_error("Z too low") }
    {% elif vol > max_vol %}
        { action_raise_error("Purge volume %.3fmm\u00B3 greater than maximum %.3fmm\u00B3" % (vol, max_vol)) }
    {% else %}
        SAVE_GCODE_STATE NAME=PURGE
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z{zhop} F{tspeed}
        {% endif %}
        G90 # Absolute positioning.
        {% if eject %}
            PURGE_HOME ZCHECK={zcheck}
        {% else %}
            G0 X{sx} Y{sy} F{tspeed}
        {% endif %}
        M106 S255
        M83 # relative extruder
        # purge
        {% set dist = vol / cfg.groove_csa %}
        {% set feed = flow / cfg.groove_csa %}
        {% set fil = vol / cfg.fil_csa %}
        # Sometimes, randomly it almost seems, klipper decides it really wants ascii in some processing happening in action_respond_info. Maybe some logging going wrong?
        #{ action_respond_info("purge: vol=%.3fmm\u00B3 flow=%.3fmm\u00B3/s dist=%.3fmm fil=%.3fmm rate=%.3fmm/s" % (vol, flow, dist, fil, feed)) }
        { action_respond_info("purge: vol=%.3fmm3 flow=%.3fmm3/s dist=%.3fmm fil=%.3fmm rate=%.3fmm/s" % (vol, flow, dist, fil, feed)) }
        G1 X{sx + dist} E{fil} F{feed * 60}
        # retraction
        {% set ret_fil = retvol / cfg.fil_csa %}
        G1 E-{ret_fil} F{retspeed * 60}
        # brush
        G0 X{cfg.brush_start[0]} Y{cfg.brush_start[1]} F{cfg.brush_speed * 60}
        M106 S{initial_fan_speed * 255|int}
        {% if brush_clear == 1 %}
            G0 X{cfg.brush_start[0] + cfg.brush_clear} F{tspeed}
        {% endif %}
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z-{zhop} F{tspeed}
        {% endif %}
        RESTORE_GCODE_STATE NAME=PURGE
    {% endif %}

[gcode_macro PURGE_HOME]
# Position the toolhead close to the ejection system. Turn on the fan. Wait for
# the end of the cooling period if necessary. Eject the pellet. Position the
# toolhead above the purging groove. Turn off the fan.
#
# Example of use in prusaslicer tool change gcode:
#    {if has_wipe_tower}
#    T{next_extruder} ; ERCF swap { filament_preset[current_extruder] }
#    {else}
#    PURGE_HOME ZHOP=0.2 ZCHECK=0
#    T{next_extruder} ; ERCF swap { filament_preset[current_extruder] }
#    PURGE VOL=150 RET=0.5 RETSPEED=35 EJECT=0 BRUSH_CLEAR=0 ZCHECK=0
#    {endif}
#
# Parameters:
#   ZHOP=-1
#   ZCHECK=1
gcode:
    # Z hop if positive value.
    {% set zhop = params.ZHOP|default(-1)|float %}
    # Raise an error if z < z_min.
    {% set zcheck = params.ZCHECK|default(1)|int %}

    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}
    {% set mp = printer['gcode_macro PURGE'] %}
    {% set tspeed = cfg.travel_speed * 60 %}
    {% set sx = cfg.groove_start[0] %}
    {% set sy = cfg.groove_start[1] %}
    {% set cx = sx + cfg.cooling_pos[0] %}
    {% set cy = sy + cfg.cooling_pos[1] %}
    {% set initial_fan_speed = printer.fan.speed / printer.configfile.settings.fan.max_power %}

    {% if "xyz" not in printer.toolhead.homed_axes %}
        { action_raise_error("Not homed") }
    {% elif zcheck and printer.toolhead.position.z < cfg.z_min %}
        { action_raise_error("Z too low") }
    {% else %}
        SAVE_GCODE_STATE NAME=PURGE_HOME
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z{zhop} F{tspeed}
        {% endif %}
        G90 # absolute
        G0 X{cx} Y{cy} F{tspeed}
        M106 S255
        {% if printer.idle_timeout.state == "Printing" %}
             {% set elapsed = printer.idle_timeout.printing_time - mp.last_purge %}
             {% if elapsed > 0.0 and elapsed < cfg.cooling_period %}
                { action_respond_info("Waiting for pellet to cool...") }
                G4 P{cfg.cooling_period - elapsed}
             {% endif %}
        {% endif %} 
        SET_GCODE_VARIABLE MACRO=PURGE VARIABLE=last_purge VALUE={printer.idle_timeout.printing_time}
        PURGE_EJECT
        G0 X{sx} Y{sy} F{tspeed}
        {% if zhop >= 0.0 %}
            G91 # relative
            G0 Z-{zhop} F{tspeed}
        {% endif %}
        M106 S{initial_fan_speed * 255|int}
        RESTORE_GCODE_STATE NAME=PURGE_HOME
    {% endif %}

[gcode_macro PURGE_EJECT]
description: Eject.
# This macro ejects the pellet.
#
# Async ejection state.
#  -1: unknown.
#  0: closed.
#  1: opening.
#  2: closing.
#
# TODO: Waiting for some async gcode synced to the print time in klipper to make it truly async.
variable_e_state: -1
variable_e_stroke: 0
gcode:
    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}
    {% set dwell_s = cfg.servo_dwell / 1000 %}

    {% if e_state == -1 %} # unknown
        # Add half a stroke for closing first just in case. Since we do not know the state.
        SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_state VALUE=1 # opening
    {% else %}
        #PURGE_EJECT_WAIT
        SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_state VALUE=2 # closing
    {% endif %}
    SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_stroke VALUE={cfg.ejection_count}
    _PURGE_EJECT_WAIT

[gcode_macro _PURGE_EJECT_WAIT]
description: Wait for the last ejection to complete.
gcode:
    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}
    {% set mp = printer['gcode_macro PURGE_EJECT'] %}
    {% if mp.e_state > 0 %}
        {% set dwell_ms = cfg.servo_dwell %}
        UPDATE_DELAYED_GCODE ID=purge_ejection DURATION=0.0 # cancel async.
        G4 P{dwell_ms|int} # Because we don't know how long elapsed since
        # the delayed gcode was scheduled last; in the worst case; we have
        # doubled the total dwell time. Not a big deal in practice.

        # Compute the number of steps to complete the state machine.
        # (strokes left) * (Closing + Opening) + half-stroke (Opening) + Turnoff.
        {% set steps = mp.e_stroke * 2 + (mp.e_state == 1)|int + 1 %}
        # And drive the state machine to completion.
        {% for _ in range(steps) %}
            _PURGE_EJECTION_NEXT SYNC=1
        {% endfor %}
    {% endif %}

[gcode_macro _PURGE_EJECTION_NEXT]
# Move the state machine forward.
gcode:
    {% set sync = params.SYNC|int %}

    {% set cfg = printer['gcode_macro _PURGE_CFG'] %}
    {% set mp = printer['gcode_macro PURGE_EJECT'] %}
    {% set done = false %}

    #{ action_respond_info("%s %s" % (mp.e_state, mp.e_stroke)) }
    {% if mp.e_state == 1 %} # opening
        # Opened, now we close.
        SET_SERVO SERVO=eap_servo ANGLE=0
        SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_state VALUE=2 # closing
    {% elif mp.e_state == 2 %} # closing
        {% if mp.e_stroke > 0 %}
            # Closed, open again.
            SET_SERVO SERVO=eap_servo ANGLE=180
            SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_stroke VALUE={mp.e_stroke - 1}
            SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_state VALUE=1 # opening
        {% else %}
            # Closed and done.
            SET_SERVO SERVO=eap_servo WIDTH=0 # turn off servo
            SET_GCODE_VARIABLE MACRO=PURGE_EJECT VARIABLE=e_state VALUE=0 # closed
            {% set done = true %}
        {% endif %}
    {% else %} # unknown or closed
        { action_raise_error("invalid state %d" % mp.e_state) }
    {% endif %}

    {% if not done %}
        {% if sync %}
            G4 P{cfg.servo_dwell}
        {% else %}
            UPDATE_DELAYED_GCODE ID=purge_ejection DURATION={cfg.servo_dwell/1000}
        {% endif %}
    {% endif %}

[delayed_gcode purge_ejection]
gcode:
    _PURGE_EJECTION_NEXT SYNC=0