Vendor: LowRider, 6 gates, selector ServoSelector. Traced against Happy Hare c54c736, harness profile low_rider.
MMU_TYPE_LOW_RIDER_1_0 does select SERVO_SELECTOR (installer/mmu_types/Kconfig.low_rider:6) and trades the selector stepper for one RC servo -- [mmu_unit unit0] selector_servo: unit0_selector_servo, with no selector [mmu_stepper] section -- beside the gear stepper. The servo part is HH's CHOICE_SERVO_TYPE default SERVO_TYPE_DM996 (Kconfig.low_rider:49-50), duration 0.6, dwell 1.0, always_active 0, bypass -1, release 0, max 180 degrees (Kconfig.low_rider:53-63); the type's implys also give filament_always_gripped: 1 and variable_rotation_distances: 1 (Kconfig.low_rider:9-10). klipper-mmu drives it as a SERVO selector (KLIPPER_MMU_SELECTOR_KIND_SERVO) on KLIPPER_MMU_PINS_SERVO, Klipper's scheduled software PWM on any GPIO: one angle per gate, seeded from the table below and replaced by angles saved with KLIPPER_MMU_CALIBRATE_SELECTOR, release angle 0 and a 1.0 s dwell, the same as Happy Hare. There is no selector axis to home. Software candidate: it builds and passes the simulators, but has not run on real hardware.PARAM_NUM_GATES default 6 (installer/mmu_types/Kconfig.low_rider:33), recorded as device.gates: 6 and [mmu_unit unit0] num_gates: 6. The shipped angle table is written per gate count (Kconfig.low_rider:68-72), so the 6-gate default is the table below and nothing is rescaled.PARAM_SERVO_GATE_ANGLES default 30, 60, 90, 120, 150, 180 (installer/mmu_types/Kconfig.low_rider:67-72) -- gate 0 at 30 degrees, gate 5 at 180, with 0 reserved for the release position. The file's own comment: 'Reserve 0 degrees for the release position, then distribute gates evenly over the remaining selector travel up to 180 degrees'. The render carries the same table (selector_servo plus servo_gate_angles), and these are klipper-mmu's default gate angles (KLIPPER_MMU_SELECTOR_SERVO_GATE_ANGLES_DEG) until angles measured with KLIPPER_MMU_CALIBRATE_SELECTOR replace them.unit0:mmu_shared_exit (the only switch the render declares, mmu_shared_exit_switch_pin), then LOAD runs Homing filament to extruder endstop on endstop extruder with endstop_pos: 700 (layout extruder = 700) and never trips it -- the harness records !! Endstop 'extruder' not found and Failed to reach extruder 'extruder' endstop after moving 0.0mm, leaving operations.load.end.tip = 682, filament_pos: 4, gate_status: 1, with that error latched into UNLOAD and EJECT too. That is HH's configured arrival, not a harness defect: the type imply MMU_HAS_SENSOR_EXTRUDER (installer/mmu_types/Kconfig.low_rider:7) and the render sets extruder_homing_endstop: extruder, while this baseline profile declares [mmu_toolhead default] extruder_switch_pin empty. klipper-mmu does not fabricate the missing switch either: LOAD ends at a local toolhead switch or at FPS arrival, so a build wires one of the two.unit0:mmu_shared_exit (layout 10.0) and parks gate_preload_parking_distance: -25 mm behind it: operations.preload.end.tip = -15 (end.offset = -25.0 behind the switch). Same -25 as Pico MMU; note ViViD parks forward +10 instead.unit0:mmu_shared_exit (10.0) and parks gate_parking_distance: -25 mm behind it: operations.unload.end.tip = -15.000001, gate_status: 2. The errors recorded here are the latched LOAD extruder-endstop failure, not this operation's own.gate_final_eject_distance: 20 mm from the -15.000001 park to operations.eject.end.tip = -35.000001 with no endstop (homing: 0) -- the same 20 mm as MMX, not ERCF's longer gate clear. Its recorded error is the latched LOAD failure.[mmu_stepper] section for this type). [mmu_sensors unit0] declares only mmu_shared_exit_switch_pin, so the device's gate sensing is that single shared switch -- PRELOAD has no gate switch of its own, and the layout's mmu_entry/mmu_exit positions are the harness's 1-D path, not per-gate hardware.[mmu_toolhead default]| Key | Value |
|---|---|
extruder_switch_pin |
`` |
toolhead_switch_pin |
`` |
register_toolhead_sensors |
1 |
toolhead_extruder_to_nozzle |
72 |
toolhead_sensor_to_nozzle |
62 |
toolhead_entry_to_extruder |
8 |
toolhead_residual_filament |
2 |
toolhead_ooze_reduction |
0 |
[mmu_unit unit0]| Key | Value |
|---|---|
vendor |
LowRider |
version |
1.0 |
num_gates |
6 |
display_name |
LowRider-0 |
toolhead |
default |
extruder_name |
extruder |
selector_servo |
unit0_selector_servo |
gear_stepper |
unit0_gear |
selector_type |
ServoSelector |
variable_bowden_lengths |
0 |
variable_rotation_distances |
1 |
require_bowden_move |
1 |
filament_always_gripped |
1 |
show_bypass |
0 |
[mmu_stepper unit0_gear]| Key | Value |
|---|---|
step_pin |
unit0:PD4 |
dir_pin |
unit0:PD3 |
enable_pin |
!unit0:PD5 |
rotation_distance |
23 |
gear_ratio |
80:20 |
microsteps |
16 |
full_steps_per_rotation |
200 |
extra_endstops |
`` |
mmu_gear_touch=tmc2209_unit0_gear |
virtual_endstop |
[mmu_sensors unit0]| Key | Value |
|---|---|
mmu_shared_exit_switch_pin |
^unit0:PA15 |
register_mmu_sensors |
1 |
| Key | Value |
|---|---|
log_level |
1 |
log_file_level |
2 |
log_statistics |
1 |
log_visual |
1 |
log_startup_status |
1 |
log_m117_messages |
1 |
suppress_klipper_warnings |
0 |
extruder_load_speed |
16 |
extruder_unload_speed |
16 |
extruder_sync_load_speed |
18 |
extruder_sync_unload_speed |
18 |
extruder_homing_speed |
16 |
extruder_accel |
1500 |
macro_toolhead_max_accel |
0 |
macro_toolhead_min_cruise_ratio |
0.5 |
force_form_tip_standalone |
1 |
form_tip_macro |
_MMU_FORM_TIP |
extruder_form_tip_current |
100 |
slicer_tip_park_pos |
0 |
force_purge_standalone |
1 |
purge_macro |
_MMU_PURGE |
extruder_purge_current |
100 |
endless_spool_enabled |
0 |
endless_spool_on_load |
0 |
endless_spool_eject_gate |
-1 |
endless_spool_groups |
`` |
spoolman_support |
off |
spoolman_pending_id_timeout |
20 |
spoolman_led_segment |
gate_status |
spoolman_nfc_auto_create |
0 |
t_macro_color |
slicer |
console_stat_columns |
unload, load, post_load, total |
console_stat_rows |
total, total_average, job, job_average, last |
console_gate_stat |
emoticon |
console_always_output_full |
1 |
console_show_colored_text |
1 |
console_show_filament_color |
1 |
timeout_pause |
72000 |
disable_heater |
600 |
default_extruder_temp |
200 |
extruder_temp_variance |
2 |
startup_reset_ttg_map |
0 |
show_error_dialog |
1 |
strict_filament_recovery |
0 |
filament_recovery_on_pause |
1 |
retry_tool_change_on_error |
0 |
bypass_autoload |
1 |
print_start_detection |
1 |
gcode_load_sequence |
0 |
gcode_unload_sequence |
0 |
drying_data |
{ |
'pla' |
(45, 300), |
'pla+' |
(55, 300), |
'petg' |
(60, 300), |
'tpu' |
(55, 300), |
'abs' |
(70, 300), |
'abs+' |
(75, 300), |
'asa' |
(65, 300), |
'nylon' |
(75, 600), |
'pc' |
(75, 600), |
'pva' |
(75, 600), |
'hips' |
(75, 600) |
update_trsync |
0 |
update_bit_max_time |
1 |
update_aht10_commands |
0 |
pause_macro |
PAUSE |
action_changed_macro |
_MMU_ACTION_CHANGED |
print_state_changed_macro |
_MMU_PRINT_STATE_CHANGED |
mmu_event_macro |
_MMU_EVENT |
post_preload_macro |
_MMU_POST_PRELOAD |
pre_unload_macro |
_MMU_PRE_UNLOAD |
post_form_tip_macro |
_MMU_POST_FORM_TIP |
post_unload_macro |
_MMU_POST_UNLOAD |
pre_load_macro |
_MMU_PRE_LOAD |
post_load_macro |
_MMU_POST_LOAD |
unload_sequence_macro |
_MMU_UNLOAD_SEQUENCE |
load_sequence_macro |
_MMU_LOAD_SEQUENCE |
servo_min_angle |
0 |
servo_max_angle |
180 |
servo_gate_angles |
30, 60, 90, 120, 150, 180 |
servo_bypass_angle |
-1 |
servo_release_angle |
0 |
servo_duration |
0.6 |
servo_dwell |
1.0 |
servo_always_active |
0 |
gear_load_speed |
100 |
gear_load_accel |
100 |
gear_unload_speed |
80 |
gear_unload_accel |
100 |
gear_homing_speed |
50 |
virtual_sensor_homing_speed |
15 |
gear_short_move_speed |
80 |
gear_short_move_accel |
400 |
gear_short_move_threshold |
70 |
gate_homing_endstop |
mmu_shared_exit |
gate_homing_max |
1000 |
gate_parking_distance |
-25 |
gate_preload_endstop |
`` |
gate_preload_homing_max |
1000 |
gate_preload_parking_distance |
-25 |
gate_preload_attempts |
2 |
gate_final_eject_distance |
20 |
bowden_homing_max |
2000 |
bowden_load_homing_buffer |
20 |
bowden_unload_homing_buffer |
40 |
extruder_homing_endstop |
extruder |
extruder_homing_max |
100 |
extruder_collision_homing_current |
30 |
toolhead_unload_safety_margin |
10 |
toolhead_post_load_tighten |
60 |
toolhead_post_load_tension_adjust |
1 |
toolhead_entry_tension_test |
1 |
sync_to_extruder |
1 |
sync_gear_current |
100 |
sync_form_tip |
0 |
sync_purge |
0 |
autocal_bowden_length |
1 |
autotune_bowden_length |
0 |
skip_cal_rotation_distance |
1 |
autotune_rotation_distance |
0 |
Steps/mm (gear): 556.5217391304348
| Phase | Motor | Homing | Endstop | Dist | Speed | Accel | Actual | Homed |
|---|---|---|---|---|---|---|---|---|
| Initial homing to unit0:mmu_shared_exit sensor | gear | 1 | unit0:mmu_shared_exit | 1000.00 | 50.0 | 100.0 | 50.00 | True |
| Final parking | gear | 0 | -25.00 | 80.0 | 400.0 | -25.00 | False |
Ends at tip -15.00 = unit0:mmu_shared_exit - 25.00 mm (filament_pos=0, gate_status=1).
No motion (already in the requested state).
| Phase | Motor | Homing | Endstop | Dist | Speed | Accel | Actual | Homed |
|---|---|---|---|---|---|---|---|---|
| Initial homing to unit0:mmu_shared_exit sensor | gear | 1 | unit0:mmu_shared_exit | 1000.00 | 50.0 | 100.0 | 25.00 | True |
| Fast loading move through bowden | gear | 0 | 672.00 | 100.0 | 100.0 | 672.00 | False | |
| Homing filament to extruder endstop | gear | 1 | extruder | 128.00 | 50.0 | 100.0 | 0.00 | False |
Ends at tip 682.00 = extruder - 18.00 mm (filament_pos=4, gate_status=1).
Errors: ["!! Endstop 'extruder' not found", "!! MMU issue: Load sequence failed because:\nFailed to reach extruder 'extruder' endstop after moving 0.0mm.\nOccurred when loading tool: > T0"]
| Phase | Motor | Homing | Endstop | Dist | Speed | Accel | Actual | Homed |
|---|---|---|---|---|---|---|---|---|
| Fast unloading move through bowden | gear | 0 | -660.00 | 80.0 | 100.0 | -660.00 | False | |
| Reverse homing off unit0:mmu_shared_exit sensor | gear | -1 | unit0:mmu_shared_exit | -1040.00 | 50.0 | 100.0 | -12.00 | True |
| Final parking | gear | 0 | -25.00 | 80.0 | 400.0 | -25.00 | False |
Ends at tip -15.00 = unit0:mmu_shared_exit - 25.00 mm (filament_pos=0, gate_status=2).
Errors: ["!! Endstop 'extruder' not found", "!! MMU issue: Load sequence failed because:\nFailed to reach extruder 'extruder' endstop after moving 0.0mm.\nOccurred when loading tool: > T0"]
| Phase | Motor | Homing | Endstop | Dist | Speed | Accel | Actual | Homed |
|---|---|---|---|---|---|---|---|---|
| Ejecting filament out of gate | gear | 0 | -20.00 | 80.0 | 400.0 | -20.00 | False |
Errors: ["!! Endstop 'extruder' not found", "!! MMU issue: Load sequence failed because:\nFailed to reach extruder 'extruder' endstop after moving 0.0mm.\nOccurred when loading tool: > T0"]
| Upstream concept | AFC | Happy Hare | klipper-mmu today | Status |
|---|---|---|---|---|
| Lane / gate | [AFC_stepper laneN], unit: X:N | gate index, unit0_gear_ | lane_count, per-lane feeder driver | mapped |
| Prep / entry switch | prep: (TRG) | mmu_entry_ | has_bay_sensors, KLIPPER_MMU_PINS_BAY | mapped |
| Load / exit switch | load: (LOAD) | mmu_exit_ | has_load_sensors, KLIPPER_MMU_PINS_LOAD | mapped |
| Hub / shared exit | [AFC_hub] switch_pin | mmu_shared_exit | has_hub_sensor, PINS_HUB | mapped |
| Virtual hub | switch_pin: virtual + use_dist_hub | no shared exit + gate_homing_endstop: mmu_exit | load_is_virtual_hub | mapped |
| Bowden length | afc_bowden_length / dist_hub per lane | mmu_calibration_bowden_lengths (per gate if variable) | fps_calibrated_steps (one per unit) | gap: per-lane |
| Toolhead switch | pin_tool_start / pin_tool_end, tool_stn | [mmu_toolhead] toolhead_switch_pin, toolhead_sensor_to_nozzle | has_toolhead_sensor, PINS_TOOLHEAD; nozzle distances host-owned | mapped (boundary), host (distances) |
| Switched buffer | [AFC_buffer] advance_pin/trailing_pin + multipliers | [mmu_buffer] compression_pin/tension_pin | has_proportional_buffer=false, PINS_BUFFER_A/B switched | mapped for follow; gap: ramming arrival |
| Proportional buffer (PSF) | AFCFPSBuffer adc_pin, neutral/low/high, P+I | analog_pin, max_compression/tension, threshold; EKF/two-level | DiffA/DiffB pair only (km_diff_adc_config_t) | gap: single-ended ADC frontend |
| FPS (OpenAMS) | AFC_FPS.cfg | n/a | DiffA/DiffB + fps_arrival | mapped |
| Espooler / assist | AFC_assist.py, espooler.assist(pwm) | [mmu_espooler] burst/rewind | has_powered_rewind (KLIPPER_MMU_POWERED_REWIND), PWM duty, current regulator | mapped (on by default for BoxTurtle and Claymore); EMU none |
| Encoder | n/a in EMU | [mmu_encoder], encoder homing | has_encoder (KLIPPER_MMU_ENCODER), PINS_ENCODER_A, optional B: clog/stall and progress checks, CALIBRATE to a toolhead switch | mapped (on by default for ERCF); encoder homing not a mode |
| Selector | HTLF lobes, ViViD/Claymore selector switches | SELECTOR_REGISTRY classes | has_selector, KLIPPER_MMU_SELECTOR_KIND_LINEAR/ROTARY/SERVO/INDEXED; homes before first use; KLIPPER_MMU_CALIBRATE_SELECTOR | mapped |
| Grip / servo | n/a EMU | servo_* | KLIPPER_MMU_PINS_SERVO (Klipper software PWM, any GPIO): LINEAR grip angles, SERVO per-gate angles | mapped |
| Speeds | long/short/hub/calibration modes | load/unload/short/homing/virtual-sensor speeds | feed/rewind velocity, accel/decel, cruise/crawl | mapped in shape; per-device numbers vary |
| Currents | run_current, print_current (follow) | run/hold, sync_gear_current % | run/hold only | gap: follow current |
| Homing budget / attempts | homing_overshoot, homing_delta, attempt loops | gate_homing_max, *_attempts, bowden_homing_max | timeouts in ms, KM_LOAD_ATTEMPTS 3, arrival min/max steps | mapped as deadlines; distance vs time is a translation choice |
| Parking / clearance | hub_clear_move_dis, extruder_clear_dis, park_dist | gate_parking_distance, gate_final_eject_distance | unload_hub_clear_steps; EJECT to BAY-clear | partly mapped; decision |
| Tip forming, cut, purge, park | AFC macros, AFC_form_tip.py | _MMU_FORM_TIP, _MMU_PARK, purge | host/OpenAMS macros | host-only |
| Runout / endless spool | handle_prep_runout, _perform_infinite_runout | mmu_endless_spool.py | host reducer + firmware runout evidence | host-only (with firmware evidence) |
| LEDs, buttons, fans, environment, heater, NFC, Spoolman | many | many | out of scope for firmware | not-applicable |
Not modelled by this dossier: motion timing/step generation, macro bodies, espooler and FlowGuard behaviour, real sensor electrics, and calibration (seeded, not measured).