Faults and warnings

The S1 reports what it is doing as a state, what went wrong as faults, and what is getting close to wrong as warnings. All three are in every telemetry frame, and Tercio Control shows them on each motor’s page.

States

Value	State	Meaning
0	Disabled	Bridge off. The shaft turns freely.
1	Holding	Closed loop, at rest, holding the target.
2	Moving	Following a position move.
3	Velocity	Turning at a set velocity.
4	Step/Dir	Following the STEP/DIR/EN inputs.
5	Calibrating	Calibrate is running.
6	Homing	Home is running.
7	Auto-tuning	AutoTune is running.
8	Fault	A hard fault switched the bridge off. ClearFaults once the cause is gone.

Faults

A fault latches: it stays set until it is cleared, even if the cause went away. There are two kinds:

• Hard faults switch the bridge off and put the axis in the Fault state. The motor has no holding torque.
• Soft faults stop the motion. The axis stays enabled.

Bit	Fault	Effect	What to do
0 0x0001	Over-temperature OVER_TEMPERATURE	Bridge off	The board is too hot. Let it cool, improve airflow or lower the run current.
1 0x0002	Driver over-temperature DRIVER_OVER_TEMP	Bridge off	The TMC2209 shut down on heat. Lower the current or add cooling.
2 0x0004	Driver fault DRIVER_FAULT	Bridge off	The driver switched its bridge off: short circuit or supply problem. Check the motor wiring.
3 0x0008	Driver not responding DRIVER_COMM	Bridge off	The TMC2209 stopped answering over UART. Check the motor supply.
4 0x0010	Encoder ENCODER	Bridge off	No valid encoder readings. Check the magnet and the encoder connection.
5 0x0020	Stall STALL	Stops motion	The shaft fell behind the command. Reduce speed or acceleration, raise the current, or check for a blockage.
6 0x0040	Calibration failed CALIBRATION_FAILED	Stops motion	The encoder did not follow the motor. Check the magnet, steps per revolution and gear ratio.
7 0x0080	Homing failed HOMING_FAILED	Stops motion	No switch or hard stop was found in time, or the axis was blocked.
8 0x0100	Command timeout COMMAND_TIMEOUT	Stops motion	The host went quiet while the axis was moving, so it stopped.

Clearing faults

1. Fix the cause using the table above.
2. Send ClearFaults (Tercio Control: Clear fault on the red banner; Python: motor.clear_faults()). If the cause is still there, the S1 refuses with Faulted and the fault stays.
3. After a hard fault, enable the motor again.

Soft faults also clear on their own when the next move starts: a new MoveTo, MoveBy or SetVelocity clears Stall and Command timeout; starting a procedure clears Calibration failed and Homing failed as well.

How fast does the host hear about it? A new fault goes out at once on the event ID (0x080 + node), without waiting for the next telemetry frame. In Python, set bus.on_fault.

Warnings

Warnings are live, not latched: each one is set while its condition lasts. They never stop the motor by themselves.

Bit	Warning	Meaning
0 0x0001	Running hot TEMPERATURE_HIGH	The board is within 10 °C of the shutdown temperature.
1 0x0002	Driver near thermal limit DRIVER_PRE_WARNING	The TMC2209 reports its pre-warning temperature.
2 0x0004	Magnet too weak MAGNET_WEAK	The encoder magnet is too far away or too weak.
3 0x0008	Magnet too strong MAGNET_STRONG	The encoder magnet is too close or too strong.
4 0x0010	Supply voltage low SUPPLY_LOW	The supply is below 8 V.
5 0x0020	CAN errors CAN_ERROR_PASSIVE	The CAN controller is error-passive: check wiring and termination.
6 0x0040	Motor disconnected? OPEN_LOAD	The driver sees no current in a coil while enabled: a motor wire may be loose.
7 0x0080	Saving settings failed STORAGE	The last SaveConfig failed.

Status flags

Telemetry also carries eight flags.

Bit	Flag	Set when
0 0x01	enabled	The bridge is on.
1 0x02	calibrated	Calibration has been done (and saved).
2 0x04	homed	Home succeeded since power-up.
3 0x08	settled	At the target, within the deadband.
4 0x10	limitMin	The IN1 switch is active.
5 0x20	limitMax	The IN2 switch is active.
6 0x40	movePending	A move is queued, waiting for Sync.
7 0x80	extEnable	The step/dir EN input is active.

Reporting a problem

On the motor’s Diagnostics tab, Copy report puts the motor’s identity, settings, latest telemetry with its faults and warnings, and link statistics on the clipboard. Paste it into your message.