stepper_brick

func (*StepperBrick) DeregisterAllDataCallback ¶

func (device *StepperBrick) DeregisterAllDataCallback(registrationId uint64)

Remove a registered All Data callback.

func (*StepperBrick) DeregisterNewStateCallback ¶

func (device *StepperBrick) DeregisterNewStateCallback(registrationId uint64)

Remove a registered New State callback.

func (*StepperBrick) DeregisterPositionReachedCallback ¶

func (device *StepperBrick) DeregisterPositionReachedCallback(registrationId uint64)

Remove a registered Position Reached callback.

func (*StepperBrick) DeregisterUnderVoltageCallback ¶

func (device *StepperBrick) DeregisterUnderVoltageCallback(registrationId uint64)

Remove a registered Under Voltage callback.

func (*StepperBrick) Disable ¶

func (device *StepperBrick) Disable() (err error)

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

Warning

Disabling the driver chip while the motor is still turning can damage the
driver chip. The motor should be stopped calling Stop function
before disabling the motor power. The Stop function will **not**
wait until the motor is actually stopped. You have to explicitly wait for the
appropriate time after calling the Stop function before calling
the Disable function.

func (*StepperBrick) DisableStatusLED ¶

func (device *StepperBrick) DisableStatusLED() (err error)

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)

func (*StepperBrick) DriveBackward ¶

func (device *StepperBrick) DriveBackward() (err error)

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

func (*StepperBrick) DriveForward ¶

func (device *StepperBrick) DriveForward() (err error)

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

func (*StepperBrick) Enable ¶

func (device *StepperBrick) Enable() (err error)

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

func (*StepperBrick) EnableStatusLED ¶

func (device *StepperBrick) EnableStatusLED() (err error)

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)

func (*StepperBrick) FullBrake ¶

func (device *StepperBrick) FullBrake() (err error)

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 Stop if you just want to stop the motor.

func (*StepperBrick) GetAPIVersion ¶

func (device *StepperBrick) GetAPIVersion() [3]uint8

Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

func (*StepperBrick) GetAllData ¶

func (device *StepperBrick) GetAllData() (currentVelocity uint16, currentPosition int32, remainingSteps int32, stackVoltage uint16, externalVoltage uint16, currentConsumption uint16, err error)

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 RegisterAllDataCallback callback.

func (*StepperBrick) GetAllDataPeriod ¶

func (device *StepperBrick) GetAllDataPeriod() (period uint32, err error)

Returns the period as set by SetAllDataPeriod.

func (*StepperBrick) GetChipTemperature ¶

func (device *StepperBrick) GetChipTemperature() (temperature int16, err error)

Returns the temperature 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.

func (*StepperBrick) GetCurrentConsumption ¶

func (device *StepperBrick) GetCurrentConsumption() (current uint16, err error)

Returns the current consumption of the motor.

func (*StepperBrick) GetCurrentPosition ¶

func (device *StepperBrick) GetCurrentPosition() (position int32, err error)

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 (SetTargetPosition, SetSteps, DriveForward or DriveBackward). It also is possible to reset the steps to 0 or set them to any other desired value with SetCurrentPosition.

func (*StepperBrick) GetCurrentVelocity ¶

func (device *StepperBrick) GetCurrentVelocity() (velocity uint16, err error)

Returns the *current* velocity of the stepper motor.

func (*StepperBrick) GetDecay ¶

func (device *StepperBrick) GetDecay() (decay uint16, err error)

Returns the decay mode as set by SetDecay.

func (*StepperBrick) GetExternalInputVoltage ¶

func (device *StepperBrick) GetExternalInputVoltage() (voltage uint16, err error)

Returns the external input voltage. 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

func (*StepperBrick) GetIdentity ¶

func (device *StepperBrick) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)

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 is the position in the stack from '0' (bottom) to '8' (top).

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

func (*StepperBrick) GetMaxVelocity ¶

func (device *StepperBrick) GetMaxVelocity() (velocity uint16, err error)

Returns the velocity as set by SetMaxVelocity.

func (*StepperBrick) GetMinimumVoltage ¶

func (device *StepperBrick) GetMinimumVoltage() (voltage uint16, err error)

Returns the minimum voltage as set by SetMinimumVoltage.

func (*StepperBrick) GetMotorCurrent ¶

func (device *StepperBrick) GetMotorCurrent() (current uint16, err error)

Returns the current as set by SetMotorCurrent.

func (*StepperBrick) GetProtocol1BrickletName ¶

func (device *StepperBrick) GetProtocol1BrickletName(port rune) (protocolVersion uint8, firmwareVersion [3]uint8, name string, err error)

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.

func (*StepperBrick) GetRemainingSteps ¶

func (device *StepperBrick) GetRemainingSteps() (steps int32, err error)

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

func (*StepperBrick) GetResponseExpected ¶

func (device *StepperBrick) GetResponseExpected(functionID Function) (bool, error)

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected. For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

See SetResponseExpected for the list of function ID constants available for this function.

func (*StepperBrick) GetSPITFPBaudrate ¶

func (device *StepperBrick) GetSPITFPBaudrate(brickletPort rune) (baudrate uint32, err error)

Returns the baudrate for a given Bricklet port, see SetSPITFPBaudrate.

.. versionadded:: 2.3.3$nbsp;(Firmware)

func (*StepperBrick) GetSPITFPBaudrateConfig ¶

func (device *StepperBrick) GetSPITFPBaudrateConfig() (enableDynamicBaudrate bool, minimumDynamicBaudrate uint32, err error)

Returns the baudrate config, see SetSPITFPBaudrateConfig.

.. versionadded:: 2.3.6$nbsp;(Firmware)

func (*StepperBrick) GetSPITFPErrorCount ¶

func (device *StepperBrick) GetSPITFPErrorCount(brickletPort rune) (errorCountACKChecksum uint32, errorCountMessageChecksum uint32, errorCountFrame uint32, errorCountOverflow uint32, err error)

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into ¶

* ACK checksum errors, * message checksum errors, * framing errors and * overflow errors.

The errors counts are for errors that occur on the Brick side. All Bricklets have a similar function that returns the errors on the Bricklet side.

.. versionadded:: 2.3.3$nbsp;(Firmware)

func (*StepperBrick) GetSendTimeoutCount ¶

func (device *StepperBrick) GetSendTimeoutCount(communicationMethod CommunicationMethod) (timeoutCount uint32, err error)

Returns the timeout count for the different communication methods.

The methods 0-2 are available for all Bricks, 3-7 only for Master Bricks.

This function is mostly used for debugging during development, in normal operation the counters should nearly always stay at 0.

.. versionadded:: 2.3.4$nbsp;(Firmware)

Associated constants:

• CommunicationMethodNone
• CommunicationMethodUSB
• CommunicationMethodSPIStack
• CommunicationMethodChibi
• CommunicationMethodRS485
• CommunicationMethodWIFI
• CommunicationMethodEthernet
• CommunicationMethodWIFIV2

func (*StepperBrick) GetSpeedRamping ¶

func (device *StepperBrick) GetSpeedRamping() (acceleration uint16, deacceleration uint16, err error)

Returns the acceleration and deacceleration as set by SetSpeedRamping.

func (*StepperBrick) GetStackInputVoltage ¶

func (device *StepperBrick) GetStackInputVoltage() (voltage uint16, err error)

Returns the stack input voltage. 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.

func (*StepperBrick) GetStepMode ¶

func (device *StepperBrick) GetStepMode() (mode StepMode, err error)

Returns the step mode as set by SetStepMode.

Associated constants:

• StepModeFullStep
• StepModeHalfStep
• StepModeQuarterStep
• StepModeEighthStep

func (*StepperBrick) GetSteps ¶

func (device *StepperBrick) GetSteps() (steps int32, err error)

Returns the last steps as set by SetSteps.

func (*StepperBrick) GetTargetPosition ¶

func (device *StepperBrick) GetTargetPosition() (position int32, err error)

Returns the last target position as set by SetTargetPosition.

func (*StepperBrick) GetTimeBase ¶

func (device *StepperBrick) GetTimeBase() (timeBase uint32, err error)

Returns the time base as set by SetTimeBase.

func (*StepperBrick) IsEnabled ¶

func (device *StepperBrick) IsEnabled() (enabled bool, err error)

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

func (*StepperBrick) IsStatusLEDEnabled ¶

func (device *StepperBrick) IsStatusLEDEnabled() (enabled bool, err error)

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

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

func (*StepperBrick) IsSyncRect ¶

func (device *StepperBrick) IsSyncRect() (syncRect bool, err error)

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

func (*StepperBrick) ReadBrickletPlugin ¶

func (device *StepperBrick) ReadBrickletPlugin(port rune, offset uint8) (chunk [32]uint8, err error)

Reads 32 bytes of firmware from the bricklet attached at the given port. The bytes are read starting at the position offset * 32.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

func (*StepperBrick) RegisterAllDataCallback ¶

func (device *StepperBrick) RegisterAllDataCallback(fn func(uint16, int32, int32, uint16, uint16, uint16)) uint64

This callback is triggered periodically with the period that is set by SetAllDataPeriod. The parameters are: the current velocity, the current position, the remaining steps, the stack voltage, the external voltage and the current consumption of the stepper motor.

func (*StepperBrick) RegisterNewStateCallback ¶

func (device *StepperBrick) RegisterNewStateCallback(fn func(State, State)) uint64

This callback is triggered whenever the Stepper Brick enters a new state. It returns the new state as well as the previous state.

func (*StepperBrick) RegisterPositionReachedCallback ¶

func (device *StepperBrick) RegisterPositionReachedCallback(fn func(int32)) uint64

This callback is triggered when a position set by SetSteps or SetTargetPosition is reached.

Note

Since we can't get any feedback from the stepper motor, this only works if the
acceleration (see SetSpeedRamping) is set smaller or equal to the
maximum acceleration of the motor. Otherwise the motor will lag behind the
control value and the callback will be triggered too early.

func (*StepperBrick) RegisterUnderVoltageCallback ¶

func (device *StepperBrick) RegisterUnderVoltageCallback(fn func(uint16)) uint64

This callback is triggered when the input voltage drops below the value set by SetMinimumVoltage. The parameter is the current voltage.

func (*StepperBrick) Reset ¶

func (device *StepperBrick) Reset() (err error)

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!

func (*StepperBrick) SetAllDataPeriod ¶

func (device *StepperBrick) SetAllDataPeriod(period uint32) (err error)

Sets the period with which the RegisterAllDataCallback callback is triggered periodically. A value of 0 turns the callback off.

func (*StepperBrick) SetCurrentPosition ¶

func (device *StepperBrick) SetCurrentPosition(position int32) (err error)

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).

func (*StepperBrick) SetDecay ¶

func (device *StepperBrick) SetDecay(decay uint16) (err error)

Sets the decay mode of the stepper motor. 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:https://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.

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

func (*StepperBrick) SetMaxVelocity ¶

func (device *StepperBrick) SetMaxVelocity(velocity uint16) (err error)

Sets the maximum velocity of the stepper motor. 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 SetTargetPosition, SetSteps, DriveForward or DriveBackward.

func (*StepperBrick) SetMinimumVoltage ¶

func (device *StepperBrick) SetMinimumVoltage(voltage uint16) (err error)

Sets the minimum voltage, below which the RegisterUnderVoltageCallback 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.

func (*StepperBrick) SetMotorCurrent ¶

func (device *StepperBrick) SetMotorCurrent(current uint16) (err error)

Sets the current with which the motor will be driven.

Warning

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

func (*StepperBrick) SetResponseExpected ¶

func (device *StepperBrick) SetResponseExpected(functionID Function, responseExpected bool) error

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

func (*StepperBrick) SetResponseExpectedAll ¶

func (device *StepperBrick) SetResponseExpectedAll(responseExpected bool)

Changes the response expected flag for all setter and callback configuration functions of this device at once.

func (*StepperBrick) SetSPITFPBaudrate ¶

func (device *StepperBrick) SetSPITFPBaudrate(brickletPort rune, baudrate uint32) (err error)

Sets the baudrate for a specific Bricklet port.

If you want to increase the throughput of Bricklets you can increase the baudrate. If you get a high error count because of high interference (see GetSPITFPErrorCount) you can decrease the baudrate.

If the dynamic baudrate feature is enabled, the baudrate set by this function corresponds to the maximum baudrate (see SetSPITFPBaudrateConfig).

Regulatory testing is done with the default baudrate. If CE compatibility or similar is necessary in your applications we recommend to not change the baudrate.

.. versionadded:: 2.3.3$nbsp;(Firmware)

func (*StepperBrick) SetSPITFPBaudrateConfig ¶

func (device *StepperBrick) SetSPITFPBaudrateConfig(enableDynamicBaudrate bool, minimumDynamicBaudrate uint32) (err error)

The SPITF protocol can be used with a dynamic baudrate. If the dynamic baudrate is enabled, the Brick will try to adapt the baudrate for the communication between Bricks and Bricklets according to the amount of data that is transferred.

The baudrate will be increased exponentially if lots of data is sent/received and decreased linearly if little data is sent/received.

This lowers the baudrate in applications where little data is transferred (e.g. a weather station) and increases the robustness. If there is lots of data to transfer (e.g. Thermal Imaging Bricklet) it automatically increases the baudrate as needed.

In cases where some data has to transferred as fast as possible every few seconds (e.g. RS485 Bricklet with a high baudrate but small payload) you may want to turn the dynamic baudrate off to get the highest possible performance.

The maximum value of the baudrate can be set per port with the function SetSPITFPBaudrate. If the dynamic baudrate is disabled, the baudrate as set by SetSPITFPBaudrate will be used statically.

.. versionadded:: 2.3.6$nbsp;(Firmware)

func (*StepperBrick) SetSpeedRamping ¶

func (device *StepperBrick) SetSpeedRamping(acceleration uint16, deacceleration uint16) (err error)

Sets the acceleration and deacceleration of the stepper motor. 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)

func (*StepperBrick) SetStepMode ¶

func (device *StepperBrick) SetStepMode(mode StepMode) (err error)

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.

Associated constants:

• StepModeFullStep
• StepModeHalfStep
• StepModeQuarterStep
• StepModeEighthStep

func (*StepperBrick) SetSteps ¶

func (device *StepperBrick) SetSteps(steps int32) (err error)

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 SetMaxVelocity and SetSpeedRamping will be used.

func (*StepperBrick) SetSyncRect ¶

func (device *StepperBrick) SetSyncRect(syncRect bool) (err error)

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

With synchronous rectification on, the decay can be changed (see :func: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.

func (*StepperBrick) SetTargetPosition ¶

func (device *StepperBrick) SetTargetPosition(position int32) (err error)

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

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

func (*StepperBrick) SetTimeBase ¶

func (device *StepperBrick) SetTimeBase(timeBase uint32) (err error)

Sets the time base of the velocity and the acceleration of the stepper brick.

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.

func (*StepperBrick) Stop ¶

func (device *StepperBrick) Stop() (err error)

Stops the stepper motor with the deacceleration as set by SetSpeedRamping.

func (*StepperBrick) WriteBrickletPlugin ¶

func (device *StepperBrick) WriteBrickletPlugin(port rune, offset uint8, chunk [32]uint8) (err error)

Writes 32 bytes of firmware to the bricklet attached at the given port. The bytes are written to the position offset * 32.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.