Tercio S1

Parameters

1 min readFirmware v2 · protocol v2

All 36 settings of the S1, grouped as in Tercio Control. Generated from the same definitions the control panel uses, so names, ranges and defaults match.

How settings work

Changes apply at once and live in RAM. SaveConfig (Tercio Control: Save to motor; Python: motor.save()) writes them all to flash. Calibration, homing and auto-tune save their own results.
Some can only change in a certain state. When stopped settings are refused with Busy while the motor moves; When disabled ones need the bridge off. The badge on each setting says which.
Positions, speeds and accelerations are in turns on the wire (turns, turns/s, turns/s²). Tercio Control shows them in your chosen unit; the libraries’ set_param takes turns.
On the wire, a value is always 4 little-endian bytes: integers zero-extended, booleans 0 or 1, floats as IEEE 754 single precision. The reply to SetParam carries the value as applied. See GetParam and SetParam.
Factory reset (only while disabled) restores these defaults in RAM, keeping the node ID. Save afterwards to make it permanent.

Tercio Control can export a motor’s settings to a file and import them into another motor: the buttons are at the top of the Settings tab.

from TercioBridge import Param

motor.set_param(Param.RUN_CURRENT_MA, 1200)
motor.set_param(Param.MAX_VELOCITY, 5)         # turns/s
print(motor.get_param(Param.KP))
motor.save()

Motion

Max velocity

0x20Any time

Upper speed limit for every move.

Default: 10 turns/s
Range: 0.001 – 200 turns/s
Wire type: f32
Python: Param.MAX_VELOCITY

Max acceleration

0x21Any time

Ramp steepness for every move.

Default: 100 turns/s²
Range: 0.01 – 100000 turns/s²
Wire type: f32
Python: Param.MAX_ACCELERATION

Soft limit, min

0x28Any time

Moves never go below this. Active when min is less than max.

Default: 0 turns
Range: -1e7 – 1e7 turns
Wire type: f32
Python: Param.SOFT_LIMIT_MIN

Soft limit, max

0x29Any time

Moves never go above this.

Default: 0 turns
Range: -1e7 – 1e7 turns
Wire type: f32
Python: Param.SOFT_LIMIT_MAX

Enable at power-up

0x2AAny time

Energise and hold position as soon as the board starts.

Default: On
Range: On / Off
Wire type: bool
Python: Param.ENABLE_ON_BOOT

Position loop

Proportional gain

0x22Any time

Correction speed per unit of error. Higher is stiffer; too high oscillates.

Default: 20 1/s
Range: 0 – 1000 1/s
Wire type: f32
Python: Param.KP

Integral gain

0x23Any time

Removes steady error under constant load. Usually 0 for steppers.

Default: 0 1/s²
Range: 0 – 100000 1/s²
Wire type: f32
Python: Param.KI

Damping gain

0x24Any time

Acts on the velocity error. Usually 0.

Default: 0
Range: 0 – 10
Wire type: f32
Python: Param.KD

Deadband

0x25Any time

At rest, errors smaller than this are ignored so the motor does not hunt.

Default: 0.0005 turns
Range: 0 – 0.1 turns
Wire type: f32
Python: Param.POSITION_DEADBAND

Motor and driver

Full steps per revolution

0x10When stopped

200 for 1.8° motors, 400 for 0.9° motors.

Default: 200 steps
Range: 20 – 1000 steps
Wire type: u16
Python: Param.FULL_STEPS_PER_REV

Microsteps

0x11When stopped

The driver interpolates to 1/256 internally; 16 is a good default.

Default: 1/16
Range: 1/1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, 1/256
Wire type: u16
Python: Param.MICROSTEPS

Run current

0x12Any time

RMS coil current while moving. The board delivers up to about 1.77 A.

Default: 1500 mA
Range: 50 – 2000 mA
Wire type: u16
Python: Param.RUN_CURRENT_MA

Hold current

0x13Any time

Current at standstill, as a share of the run current.

Default: 50 %
Range: 0 – 100 %
Wire type: u8
Python: Param.HOLD_CURRENT_PCT

Quiet mode (StealthChop)

0x14When stopped

Near-silent at low speed. Above the switch speed the driver uses SpreadCycle.

Default: On
Range: On / Off
Wire type: bool
Python: Param.STEALTHCHOP

Quiet mode up to

0x15Any time

Motor speed where the driver switches to SpreadCycle. 0 keeps quiet mode at every speed.

Default: 1 motor rev/s
Range: 0 – 100 motor rev/s
Wire type: f32
Python: Param.STEALTHCHOP_MAX_VEL

Reverse direction

0x16When stopped

Flip which way is positive. No recalibration needed.

Default: Off
Range: On / Off
Wire type: bool
Python: Param.INVERT_DIRECTION

Gear ratio

0x17When stopped

Motor turns per encoder turn. 1 with the on-board encoder.

Default: 1:1
Range: 0.01 – 1000:1
Wire type: f32
Python: Param.GEAR_RATIO

Encoder

0x30When disabled

Changing the encoder clears the calibration. Disable the motor first.

Default: On-board AS5600
Range: On-board AS5600, External AS5600 (I²C), External AS5048A (SPI)
Wire type: u8
Python: Param.ENCODER_TYPE

Encoder reversed

0x31When disabled

Set by calibration. Change by hand only if you know you need to.

Default: Off
Range: On / Off
Wire type: bool
Python: Param.ENCODER_INVERT

Calibrated

0x32Read-only

Run Calibrate to set this.

Default: Off
Range: On / Off
Wire type: bool
Python: Param.CALIBRATED

Homing

Method

0x50Any time

Seek a limit switch, or push gently into a hard stop.

Default: Switch IN1 (negative)
Range: Switch IN1 (negative), Switch IN2 (positive), Hard stop, negative, Hard stop, positive
Wire type: u8
Python: Param.HOMING_MODE

Search speed

0x51Any time

Keep it slow for repeatable results.

Default: 1 turns/s
Range: 0.001 – 100 turns/s
Wire type: f32
Python: Param.HOMING_VELOCITY

Search current

0x52Any time

Reduced current while searching, so a hard stop is gentle.

Default: 800 mA
Range: 50 – 2000 mA
Wire type: u16
Python: Param.HOMING_CURRENT_MA

Back-off distance

0x53Any time

How far to move away from the trigger point before setting zero.

Default: 0.05 turns
Range: 0 – 1000 turns
Wire type: f32
Python: Param.HOMING_BACKOFF

Hard-stop sensitivity

0x54Any time

Following error that counts as hitting the stop. Smaller is more sensitive.

Default: 0.03 turns
Range: 0.001 – 100 turns
Wire type: f32
Python: Param.HOMING_STALL_ERROR

Give up after

0x55Any time

Maximum search time.

Default: 30 s
Range: 1 – 3600 s
Wire type: u16
Python: Param.HOMING_TIMEOUT_S

Inputs

Stop at limit switches

0x40Any time

IN1 blocks negative motion, IN2 blocks positive motion.

Default: Off
Range: On / Off
Wire type: bool
Python: Param.LIMIT_SWITCHES_ENABLED

Switches pull to ground

0x41When stopped

On for normally-open switches wired to GND.

Default: On
Range: On / Off
Wire type: bool
Python: Param.LIMIT_SWITCH_ACTIVE_LOW

Follow step/dir input

0x42When stopped

Take position commands from the STEP/DIR/EN connector (3.3 V logic only).

Default: Off
Range: On / Off
Wire type: bool
Python: Param.STEP_DIR_MODE

EN input active low

0x43Any time

Polarity of the external enable input.

Default: On
Range: On / Off
Wire type: bool
Python: Param.STEP_DIR_ENABLE_ACTIVE_LOW

Protection

Stall threshold

0x26Any time

Following error that counts as a stall.

Default: 0.05 turns
Range: 0.001 – 1000 turns
Wire type: f32
Python: Param.FOLLOWING_ERROR_LIMIT

Stall confirm time

0x27Any time

How long the error must persist. 0 turns stall detection off.

Default: 50 ms
Range: 0 – 10000 ms
Wire type: u16
Python: Param.STALL_TIMEOUT_MS

Shut down at

0x60Any time

Board temperature that cuts the motor current.

Default: 95 °C
Range: 40 – 125 °C
Wire type: f32
Python: Param.OVER_TEMPERATURE_C

Stop if host is silent for

0x03Any time

Stops a moving axis when commands stop arriving. 0 turns it off.

Default: 0 ms
Range: 0 – 60000 ms
Wire type: u16
Python: Param.COMMAND_TIMEOUT_MS

Communication

Node ID

0x01When stopped

Unique per motor on the bus. Takes effect immediately.

Default: 1
Range: 1 – 127
Wire type: u8
Python: Param.NODE_ID

Telemetry rate

0x02Any time

How often the motor reports its state. 100 Hz suits most setups.

Default: 100 Hz
Range: 0 – 1000 Hz
Wire type: u16
Python: Param.TELEMETRY_RATE_HZ