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Device file

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openhal: "0.1"
device: Klipper 3D printer
id: printer
match:
  mdns: _moonraker._tcp
  moonraker: { hostname: "printer*" }
connect: { moonraker: printer.local, port: 7125, timeout: 5 s }
read:
  state: { type: enum, values: [standby, printing, paused, complete, cancelled, error], every: 1 s }
  extruder_temp: { unit: degC, every: 1 s, range: [0, 320] }
  bed_temp: { unit: degC, every: 1 s, range: [0, 130] }
  progress: { unit: percent, every: 5 s }
write:
  extruder_target: { unit: degC, min: 0, max: 260, max_change_per_s: 50 }
  bed_target: { unit: degC, min: 0, max: 110, max_change_per_s: 20 }
actions:
  pause:
    description: Pause the print. Klipper parks the nozzle and keeps the heaters on.
    require: ["state == printing"]
  resume:
    description: Resume a paused print.
    require: ["state == paused"]
  cancel:
    description: Cancel the print. It can't be resumed afterwards.
    confirm: confirm-each-time
safe_state:
  - { extruder_target: 0, bed_target: 0 }
interlocks:
  - if: "extruder_target > 0 degC"
    require: "state != error"
    message: "Clear the printer error before heating."
watchdog: { heartbeat: 5 s, on_loss: hold }
hazard: medium
notes: "A print keeps running if the hub goes away, so the watchdog holds the printer's state instead of stopping the print. Klipper's own heater checks stay on either way."
provenance: { source: hand-written, by: openhal print babysitter example, at: 2026-10-24 }
confirmed: { by: owner, at: 2026-10-24, sha256: 43396b8f02a70481b9653275f22cc58f96b060ad2e31f4d80214acb26e51af1a }

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Simulated device

Id: printer
Driver: moonraker

Channels the device can change
Channel	Value	Min	Max	Rate per s	Confirm
extruder_target	0 degC	0	260	50	none
bed_target	60 degC	0	110	20	none

Read channels
Channel	Value	Simulate a reading
state	printing	Simulated reading for state
extruder_temp	160 degC	Simulated reading for extruder_temp
bed_temp	65 degC	Simulated reading for bed_temp
progress	0 %	Simulated reading for progress