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Klipper Events

Happy Hare emits Klipper events for integrations that need to react to MMU activity. Register a handler with printer.register_event_handler("mmu:xxx", callback); the callback receives the parameters listed below in order.

Events

Event Parameters Description
mmu:mmu_paused - An MMU error paused the print
mmu:mmu_resumed - The print resumed after an MMU error
mmu:enabled - MMU ENABLE=1
mmu:disabled - MMU ENABLE=0
mmu:toolchange last_tool (int), next_tool (int) A toolchange started
mmu:synced - The gear stepper became synced to the extruder
mmu:unsynced - The gear stepper became unsynced from the extruder
mmu:sync_feedback eventtime (float), state (float, -1.0..+1.0) Buffer feedback changed: tension (-) or compression (+)
mmu:initialized - Happy Hare controller initialization completed
mmu:bootup - The delayed MMU_BOOTUP sequence completed
mmu:printing eventtime (float) The print-state machine entered printing
mmu:not_printing eventtime (float) The print-state machine left printing
mmu:tool_selected tool (int) The selected tool changed
mmu:gate_selected gate (int), previous_gate (int) The selected gate changed
mmu:unit_selected unit (int), previous_unit (int) The selected unit changed
mmu:spoolid_pending - A Spoolman spool ID became pending assignment
mmu:spoolid_not_pending reread (bool) A Spoolman spool ID stopped being pending; reread allows the same tag to be read again immediately
mmu:espooler_burst gate (int), power (float, 0.0..1.0), duration (float), operation (string) An eSpooler burst started
mmu:espooler_burst_done gate (int) An eSpooler burst finished
mmu:test_gen_finished - Internal - a _MMU_TEST generator command finished

See also