NAME

Tinkerforge::BrickStepper - Drives one bipolar stepper motor with up to 38V and 2.5A per phase

CONSTANTS

DEVICE_IDENTIFIER

This constant is used to identify a Stepper Brick.

The get_identity() subroutine and the CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

DEVICE_DISPLAY_NAME

This constant represents the display name of a Stepper Brick.

CALLBACK_UNDER_VOLTAGE

This constant is used with the register_callback() subroutine to specify the CALLBACK_UNDER_VOLTAGE callback.

CALLBACK_POSITION_REACHED

This constant is used with the register_callback() subroutine to specify the CALLBACK_POSITION_REACHED callback.

CALLBACK_ALL_DATA

This constant is used with the register_callback() subroutine to specify the CALLBACK_ALL_DATA callback.

CALLBACK_NEW_STATE

This constant is used with the register_callback() subroutine to specify the CALLBACK_NEW_STATE callback.

FUNCTION_SET_MAX_VELOCITY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MAX_VELOCITY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_CURRENT_VELOCITY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_SPEED_RAMPING

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_SPEED_RAMPING

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_FULL_BRAKE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_CURRENT_POSITION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_CURRENT_POSITION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_TARGET_POSITION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_TARGET_POSITION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_STEPS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_STEPS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_REMAINING_STEPS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_STEP_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_STEP_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DRIVE_FORWARD

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DRIVE_BACKWARD

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_STOP

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_STACK_INPUT_VOLTAGE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_EXTERNAL_INPUT_VOLTAGE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_CURRENT_CONSUMPTION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_MOTOR_CURRENT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MOTOR_CURRENT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_ENABLE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DISABLE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_IS_ENABLED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_DECAY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_DECAY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_MINIMUM_VOLTAGE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MINIMUM_VOLTAGE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_SYNC_RECT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_IS_SYNC_RECT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_TIME_BASE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_TIME_BASE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_ALL_DATA

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_ALL_DATA_PERIOD

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_ALL_DATA_PERIOD

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_ENABLE_STATUS_LED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DISABLE_STATUS_LED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_IS_STATUS_LED_ENABLED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_PROTOCOL1_BRICKLET_NAME

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_CHIP_TEMPERATURE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_RESET

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_IDENTITY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTIONS

new()

Creates an object with the unique device ID *uid* and adds it to the IP Connection *ipcon*.

set_max_velocity()

Sets the maximum velocity of the stepper motor in steps per second. This function does *not* start the motor, it merely sets the maximum velocity the stepper motor is accelerated to. To get the motor running use either :func:`SetTargetPosition`, :func:`SetSteps`, :func:`DriveForward` or :func:`DriveBackward`.

get_max_velocity()

Returns the velocity as set by :func:`SetMaxVelocity`.

get_current_velocity()

Returns the *current* velocity of the stepper motor in steps per second.

set_speed_ramping()

Sets the acceleration and deacceleration of the stepper motor. The values are given in *steps/s²*. An acceleration of 1000 means, that every second the velocity is increased by 1000 *steps/s*.

For example: If the current velocity is 0 and you want to accelerate to a velocity of 8000 *steps/s* in 10 seconds, you should set an acceleration of 800 *steps/s²*.

An acceleration/deacceleration of 0 means instantaneous acceleration/deacceleration (not recommended)

The default value is 1000 for both

get_speed_ramping()

Returns the acceleration and deacceleration as set by :func:`SetSpeedRamping`.

full_brake()

Executes an active full brake.

.. warning:: This function is for emergency purposes, where an immediate brake is necessary. Depending on the current velocity and the strength of the motor, a full brake can be quite violent.

Call :func:`Stop` if you just want to stop the motor.

set_current_position()

Sets the current steps of the internal step counter. This can be used to set the current position to 0 when some kind of starting position is reached (e.g. when a CNC machine reaches a corner).

get_current_position()

Returns the current position of the stepper motor in steps. On startup the position is 0. The steps are counted with all possible driving functions (:func:`SetTargetPosition`, :func:`SetSteps`, :func:`DriveForward` or :func:`DriveBackward`). It also is possible to reset the steps to 0 or set them to any other desired value with :func:`SetCurrentPosition`.

set_target_position()

Sets the target position of the stepper motor in steps. For example, if the current position of the motor is 500 and :func:`SetTargetPosition` is called with 1000, the stepper motor will drive 500 steps forward. It will use the velocity, acceleration and deacceleration as set by :func:`SetMaxVelocity` and :func:`SetSpeedRamping`.

A call of :func:`SetTargetPosition` with the parameter *x* is equivalent to a call of :func:`SetSteps` with the parameter (*x* - :func:`GetCurrentPosition`).

get_target_position()

Returns the last target position as set by :func:`SetTargetPosition`.

set_steps()

Sets the number of steps the stepper motor should run. Positive values will drive the motor forward and negative values backward. The velocity, acceleration and deacceleration as set by :func:`SetMaxVelocity` and :func:`SetSpeedRamping` will be used.

get_steps()

Returns the last steps as set by :func:`SetSteps`.

get_remaining_steps()

Returns the remaining steps of the last call of :func:`SetSteps`. For example, if :func:`SetSteps` is called with 2000 and :func:`GetRemainingSteps` is called after the motor has run for 500 steps, it will return 1500.

set_step_mode()

Sets the step mode of the stepper motor. Possible values are:

* Full Step = 1 * Half Step = 2 * Quarter Step = 4 * Eighth Step = 8

A higher value will increase the resolution and decrease the torque of the stepper motor.

The default value is 8 (Eighth Step).

get_step_mode()

Returns the step mode as set by :func:`SetStepMode`.

drive_forward()

Drives the stepper motor forward until :func:`DriveBackward` or :func:`Stop` is called. The velocity, acceleration and deacceleration as set by :func:`SetMaxVelocity` and :func:`SetSpeedRamping` will be used.

drive_backward()

Drives the stepper motor backward until :func:`DriveForward` or :func:`Stop` is triggered. The velocity, acceleration and deacceleration as set by :func:`SetMaxVelocity` and :func:`SetSpeedRamping` will be used.

stop()

Stops the stepper motor with the deacceleration as set by :func:`SetSpeedRamping`.

get_stack_input_voltage()

Returns the stack input voltage in mV. The stack input voltage is the voltage that is supplied via the stack, i.e. it is given by a Step-Down or Step-Up Power Supply.

get_external_input_voltage()

Returns the external input voltage in mV. The external input voltage is given via the black power input connector on the Stepper Brick.

If there is an external input voltage and a stack input voltage, the motor will be driven by the external input voltage. If there is only a stack voltage present, the motor will be driven by this voltage.

.. warning:: This means, if you have a high stack voltage and a low external voltage, the motor will be driven with the low external voltage. If you then remove the external connection, it will immediately be driven by the high stack voltage

get_current_consumption()

Returns the current consumption of the motor in mA.

set_motor_current()

Sets the current in mA with which the motor will be driven. The minimum value is 100mA, the maximum value 2291mA and the default value is 800mA.

.. warning:: Do not set this value above the specifications of your stepper motor. Otherwise it may damage your motor.

get_motor_current()

Returns the current as set by :func:`SetMotorCurrent`.

enable()

Enables the driver chip. The driver parameters can be configured (maximum velocity, acceleration, etc) before it is enabled.

disable()

Disables the driver chip. The configurations are kept (maximum velocity, acceleration, etc) but the motor is not driven until it is enabled again.

is_enabled()

Returns *true* if the driver chip is enabled, *false* otherwise.

set_decay()

Sets the decay mode of the stepper motor. The possible value range is between 0 and 65535. A value of 0 sets the fast decay mode, a value of 65535 sets the slow decay mode and a value in between sets the mixed decay mode.

Changing the decay mode is only possible if synchronous rectification is enabled (see :func:`SetSyncRect`).

For a good explanation of the different decay modes see `this <http://ebldc.com/?p=86/>`__ blog post by Avayan.

A good decay mode is unfortunately different for every motor. The best way to work out a good decay mode for your stepper motor, if you can't measure the current with an oscilloscope, is to listen to the sound of the motor. If the value is too low, you often hear a high pitched sound and if it is too high you can often hear a humming sound.

Generally, fast decay mode (small value) will be noisier but also allow higher motor speeds.

The default value is 10000.

.. note:: There is unfortunately no formula to calculate a perfect decay mode for a given stepper motor. If you have problems with loud noises or the maximum motor speed is too slow, you should try to tinker with the decay value

get_decay()

Returns the decay mode as set by :func:`SetDecay`.

set_minimum_voltage()

Sets the minimum voltage in mV, below which the :func:`UnderVoltage` callback is triggered. The minimum possible value that works with the Stepper Brick is 8V. You can use this function to detect the discharge of a battery that is used to drive the stepper motor. If you have a fixed power supply, you likely do not need this functionality.

The default value is 8V.

get_minimum_voltage()

Returns the minimum voltage as set by :func:`SetMinimumVoltage`.

set_sync_rect()

Turns synchronous rectification on or off (*true* or *false*).

With synchronous rectification on, the decay can be changed (see :func:`SetDecay`). Without synchronous rectification fast decay is used.

For an explanation of synchronous rectification see `here <https://en.wikipedia.org/wiki/Active_rectification>`__.

.. warning:: If you want to use high speeds (> 10000 steps/s) for a large stepper motor with a large inductivity we strongly suggest that you disable synchronous rectification. Otherwise the Brick may not be able to cope with the load and overheat.

The default value is *false*.

is_sync_rect()

Returns *true* if synchronous rectification is enabled, *false* otherwise.

set_time_base()

Sets the time base of the velocity and the acceleration of the stepper brick (in seconds).

For example, if you want to make one step every 1.5 seconds, you can set the time base to 15 and the velocity to 10. Now the velocity is 10steps/15s = 1steps/1.5s.

The default value is 1.

get_time_base()

Returns the time base as set by :func:`SetTimeBase`.

get_all_data()

Returns the following parameters: The current velocity, the current position, the remaining steps, the stack voltage, the external voltage and the current consumption of the stepper motor.

There is also a callback for this function, see :func:`AllData`.

set_all_data_period()

Sets the period in ms with which the :func:`AllData` callback is triggered periodically. A value of 0 turns the callback off.

get_all_data_period()

Returns the period as set by :func:`SetAllDataPeriod`.

enable_status_led()

Enables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

.. versionadded:: 2.3.1$nbsp;(Firmware)

disable_status_led()

Disables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

.. versionadded:: 2.3.1$nbsp;(Firmware)

is_status_led_enabled()

Returns *true* if the status LED is enabled, *false* otherwise.

.. versionadded:: 2.3.1$nbsp;(Firmware)

get_protocol1_bricklet_name()

Returns the firmware and protocol version and the name of the Bricklet for a given port.

This functions sole purpose is to allow automatic flashing of v1.x.y Bricklet plugins.

get_chip_temperature()

Returns the temperature in °C/10 as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has an accuracy of +-15%. Practically it is only useful as an indicator for temperature changes.

reset()

Calling this function will reset the Brick. Calling this function on a Brick inside of a stack will reset the whole stack.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

get_identity()

Returns the UID, the UID where the Brick is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be '0'-'8' (stack position).

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|