Visual Basic .NET - Stepper Brick

This is the description of the Visual Basic .NET API bindings for the Stepper Brick. General information and technical specifications for the Stepper Brick are summarized in its hardware description.

An installation guide for the Visual Basic .NET API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Configuration

Download (ExampleConfiguration.vb)

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Imports System
Imports System.Threading
Imports Tinkerforge

Module ExampleConfiguration
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XXYYZZ" ' Change XXYYZZ to the UID of your Stepper Brick

    Sub Main()
        Dim ipcon As New IPConnection() ' Create IP connection
        Dim stepper As New BrickStepper(UID, ipcon) ' Create device object

        ipcon.Connect(HOST, PORT) ' Connect to brickd
        ' Don't use device before ipcon is connected

        stepper.SetMotorCurrent(800) ' 800 mA
        stepper.SetStepMode(8) ' 1/8 step mode
        stepper.SetMaxVelocity(2000) ' Velocity 2000 steps/s

        ' Slow acceleration (500 steps/s^2),
        ' Fast deacceleration (5000 steps/s^2)
        stepper.SetSpeedRamping(500, 5000)

        stepper.Enable() ' Enable motor power
        stepper.SetSteps(60000) ' Drive 60000 steps forward

        Console.WriteLine("Press key to exit")
        Console.ReadLine()

        ' Stop motor before disabling motor power
        stepper.Stop() ' Request motor stop
        stepper.SetSpeedRamping(500, _
                                5000) ' Fast deacceleration (5000 steps/s^2) for stopping
        Thread.Sleep(400) ' Wait for motor to actually stop: max velocity (2000 steps/s) / decceleration (5000 steps/s^2) = 0.4 s
        stepper.Disable() ' Disable motor power

        ipcon.Disconnect()
    End Sub
End Module

Callback

Download (ExampleCallback.vb)

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Imports System
Imports System.Threading
Imports Tinkerforge

Module ExampleCallback
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XXYYZZ" ' Change XXYYZZ to the UID of your Stepper Brick

    Dim rand As Random = New Random()

    ' Use position reached callback to program random movement
    Sub PositionReachedCB(ByVal sender As BrickStepper, ByVal position As Integer)
        Dim steps As Integer

        If rand.Next(0, 2) = 0 Then
            steps = rand.Next(1000, 5001) ' steps (forward)
            Console.WriteLine("Driving forward: " + steps.ToString() + " steps")
        Else
            steps = rand.Next(-5000, -999) ' steps (backward)
            Console.WriteLine("Driving backward: " + steps.ToString() + " steps")
        End If

        Dim vel As Integer = rand.Next(200, 2001) ' steps/s
        Dim acc As Integer = rand.Next(100, 1001) ' steps/s^2
        Dim dec As Integer = rand.Next(100, 1001) ' steps/s^2

        Console.WriteLine("Configuration (vel, acc, dec): (" + vel.ToString() + ", " + _
                          acc.ToString() + ", " + dec.ToString() + ")")

        sender.SetSpeedRamping(acc, dec)
        sender.SetMaxVelocity(vel)
        sender.SetSteps(steps)
    End Sub

    Sub Main()
        Dim ipcon As New IPConnection() ' Create IP connection
        Dim stepper As New BrickStepper(UID, ipcon) ' Create device object

        ipcon.Connect(HOST, PORT) ' Connect to brickd
        ' Don't use device before ipcon is connected

        ' Register position reached callback to subroutine PositionReachedCB
        AddHandler stepper.PositionReachedCallback, AddressOf PositionReachedCB

        stepper.Enable() ' Enable motor power
        stepper.SetSteps(1) ' Drive one step forward to get things going

        Console.WriteLine("Press key to exit")
        Console.ReadLine()

        ' Stop motor before disabling motor power
        stepper.Stop() ' Request motor stop
        stepper.SetSpeedRamping(500, _
                                5000) ' Fast deacceleration (5000 steps/s^2) for stopping
        Thread.Sleep(400) ' Wait for motor to actually stop: max velocity (2000 steps/s) / decceleration (5000 steps/s^2) = 0.4 s
        stepper.Disable() ' Disable motor power

        ipcon.Disconnect()
    End Sub
End Module

API

Since Visual Basic .NET does not support multiple return values directly, we use the ByRef keyword to return multiple values from a function.

All functions and procedures listed below are thread-safe.

Basic Functions

Class BrickStepper(ByVal uid As String, ByVal ipcon As IPConnection)

Creates an object with the unique device ID uid:

Dim stepper As New BrickStepper("YOUR_DEVICE_UID", ipcon)

This object can then be used after the IP Connection is connected.

Sub BrickStepper.SetMaxVelocity(ByVal velocity As Integer)
Parameters:
  • velocity – Type: Integer, Unit: 1 1/s, Range: [0 to 216 - 1]

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().

Function BrickStepper.GetMaxVelocity() As Integer
Returns:
  • velocity – Type: Integer, Unit: 1 1/s, Range: [0 to 216 - 1]

Returns the velocity as set by SetMaxVelocity().

Function BrickStepper.GetCurrentVelocity() As Integer
Returns:
  • velocity – Type: Integer, Unit: 1 1/s, Range: [0 to 216 - 1]

Returns the current velocity of the stepper motor.

Sub BrickStepper.SetSpeedRamping(ByVal acceleration As Integer, ByVal deacceleration As Integer)
Parameters:
  • acceleration – Type: Integer, Unit: 1 1/s², Range: [0 to 216 - 1], Default: 1000
  • deacceleration – Type: Integer, Unit: 1 1/s², Range: [0 to 216 - 1], Default: 1000

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)

Sub BrickStepper.GetSpeedRamping(ByRef acceleration As Integer, ByRef deacceleration As Integer)
Output Parameters:
  • acceleration – Type: Integer, Unit: 1 1/s², Range: [0 to 216 - 1], Default: 1000
  • deacceleration – Type: Integer, Unit: 1 1/s², Range: [0 to 216 - 1], Default: 1000

Returns the acceleration and deacceleration as set by SetSpeedRamping().

Sub BrickStepper.FullBrake()

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.

Sub BrickStepper.SetSteps(ByVal steps As Integer)
Parameters:
  • steps – Type: Integer, Range: [-231 to 231 - 1]

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.

Function BrickStepper.GetSteps() As Integer
Returns:
  • steps – Type: Integer, Range: [-231 to 231 - 1]

Returns the last steps as set by SetSteps().

Function BrickStepper.GetRemainingSteps() As Integer
Returns:
  • steps – Type: Integer, Range: [-231 to 231 - 1]

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.

Sub BrickStepper.DriveForward()

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.

Sub BrickStepper.DriveBackward()

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.

Sub BrickStepper.Stop()

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

Sub BrickStepper.SetMotorCurrent(ByVal current As Integer)
Parameters:
  • current – Type: Integer, Unit: 1 mA, Range: [100 to 2291], Default: 800

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.

Function BrickStepper.GetMotorCurrent() As Integer
Returns:
  • current – Type: Integer, Unit: 1 mA, Range: [100 to 2291], Default: 800

Returns the current as set by SetMotorCurrent().

Sub BrickStepper.Enable()

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

Sub BrickStepper.Disable()

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.

Function BrickStepper.IsEnabled() As Boolean
Returns:
  • enabled – Type: Boolean, Default: false

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

Advanced Functions

Sub BrickStepper.SetCurrentPosition(ByVal position As Integer)
Parameters:
  • position – Type: Integer, Range: [-231 to 231 - 1]

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).

Function BrickStepper.GetCurrentPosition() As Integer
Returns:
  • position – Type: Integer, Range: [-231 to 231 - 1]

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().

Sub BrickStepper.SetTargetPosition(ByVal position As Integer)
Parameters:
  • position – Type: Integer, Range: [-231 to 231 - 1]

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()).

Function BrickStepper.GetTargetPosition() As Integer
Returns:
  • position – Type: Integer, Range: [-231 to 231 - 1]

Returns the last target position as set by SetTargetPosition().

Sub BrickStepper.SetStepMode(ByVal mode As Byte)
Parameters:
  • mode – Type: Byte, Range: See constants, Default: 8

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 following constants are available for this function:

For mode:

  • BrickStepper.STEP_MODE_FULL_STEP = 1
  • BrickStepper.STEP_MODE_HALF_STEP = 2
  • BrickStepper.STEP_MODE_QUARTER_STEP = 4
  • BrickStepper.STEP_MODE_EIGHTH_STEP = 8
Function BrickStepper.GetStepMode() As Byte
Returns:
  • mode – Type: Byte, Range: See constants, Default: 8

Returns the step mode as set by SetStepMode().

The following constants are available for this function:

For mode:

  • BrickStepper.STEP_MODE_FULL_STEP = 1
  • BrickStepper.STEP_MODE_HALF_STEP = 2
  • BrickStepper.STEP_MODE_QUARTER_STEP = 4
  • BrickStepper.STEP_MODE_EIGHTH_STEP = 8
Function BrickStepper.GetStackInputVoltage() As Integer
Returns:
  • voltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]

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.

Function BrickStepper.GetExternalInputVoltage() As Integer
Returns:
  • voltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]

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

Function BrickStepper.GetCurrentConsumption() As Integer
Returns:
  • current – Type: Integer, Unit: 1 mA, Range: [0 to 216 - 1]

Returns the current consumption of the motor.

Sub BrickStepper.SetDecay(ByVal decay As Integer)
Parameters:
  • decay – Type: Integer, Range: [0 to 216 - 1], Default: 10000

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 SetSyncRect()).

For a good explanation of the different decay modes see this 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

Function BrickStepper.GetDecay() As Integer
Returns:
  • decay – Type: Integer, Range: [0 to 216 - 1], Default: 10000

Returns the decay mode as set by SetDecay().

Sub BrickStepper.SetSyncRect(ByVal syncRect As Boolean)
Parameters:
  • syncRect – Type: Boolean, Default: false

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

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

For an explanation of synchronous rectification see here.

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.

Function BrickStepper.IsSyncRect() As Boolean
Returns:
  • syncRect – Type: Boolean, Default: false

Returns true if synchronous rectification is enabled, false otherwise.

Sub BrickStepper.SetTimeBase(ByVal timeBase As Long)
Parameters:
  • timeBase – Type: Long, Unit: 1 s, Range: [0 to 232 - 1], Default: 1

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.

Function BrickStepper.GetTimeBase() As Long
Returns:
  • timeBase – Type: Long, Unit: 1 s, Range: [0 to 232 - 1], Default: 1

Returns the time base as set by SetTimeBase().

Sub BrickStepper.GetAllData(ByRef currentVelocity As Integer, ByRef currentPosition As Integer, ByRef remainingSteps As Integer, ByRef stackVoltage As Integer, ByRef externalVoltage As Integer, ByRef currentConsumption As Integer)
Output Parameters:
  • currentVelocity – Type: Integer, Unit: 1 1/s, Range: [0 to 216 - 1]
  • currentPosition – Type: Integer, Range: [-231 to 231 - 1]
  • remainingSteps – Type: Integer, Range: [-231 to 231 - 1]
  • stackVoltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]
  • externalVoltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]
  • currentConsumption – Type: Integer, Unit: 1 mA, Range: [0 to 216 - 1]

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 AllDataCallback callback.

Sub BrickStepper.SetSPITFPBaudrateConfig(ByVal enableDynamicBaudrate As Boolean, ByVal minimumDynamicBaudrate As Long)
Parameters:
  • enableDynamicBaudrate – Type: Boolean, Default: true
  • minimumDynamicBaudrate – Type: Long, Unit: 1 Bd, Range: [400000 to 2000000], Default: 400000

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.

New in version 2.3.6 (Firmware).

Sub BrickStepper.GetSPITFPBaudrateConfig(ByRef enableDynamicBaudrate As Boolean, ByRef minimumDynamicBaudrate As Long)
Output Parameters:
  • enableDynamicBaudrate – Type: Boolean, Default: true
  • minimumDynamicBaudrate – Type: Long, Unit: 1 Bd, Range: [400000 to 2000000], Default: 400000

Returns the baudrate config, see SetSPITFPBaudrateConfig().

New in version 2.3.6 (Firmware).

Function BrickStepper.GetSendTimeoutCount(ByVal communicationMethod As Byte) As Long
Parameters:
  • communicationMethod – Type: Byte, Range: See constants
Returns:
  • timeoutCount – Type: Long, Range: [0 to 232 - 1]

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.

The following constants are available for this function:

For communicationMethod:

  • BrickStepper.COMMUNICATION_METHOD_NONE = 0
  • BrickStepper.COMMUNICATION_METHOD_USB = 1
  • BrickStepper.COMMUNICATION_METHOD_SPI_STACK = 2
  • BrickStepper.COMMUNICATION_METHOD_CHIBI = 3
  • BrickStepper.COMMUNICATION_METHOD_RS485 = 4
  • BrickStepper.COMMUNICATION_METHOD_WIFI = 5
  • BrickStepper.COMMUNICATION_METHOD_ETHERNET = 6
  • BrickStepper.COMMUNICATION_METHOD_WIFI_V2 = 7

New in version 2.3.4 (Firmware).

Sub BrickStepper.SetSPITFPBaudrate(ByVal brickletPort As Char, ByVal baudrate As Long)
Parameters:
  • brickletPort – Type: Char, Range: ["a"C to "b"C]
  • baudrate – Type: Long, Unit: 1 Bd, Range: [400000 to 2000000], Default: 1400000

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.

New in version 2.3.3 (Firmware).

Function BrickStepper.GetSPITFPBaudrate(ByVal brickletPort As Char) As Long
Parameters:
  • brickletPort – Type: Char, Range: ["a"C to "b"C]
Returns:
  • baudrate – Type: Long, Unit: 1 Bd, Range: [400000 to 2000000], Default: 1400000

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

New in version 2.3.3 (Firmware).

Sub BrickStepper.GetSPITFPErrorCount(ByVal brickletPort As Char, ByRef errorCountACKChecksum As Long, ByRef errorCountMessageChecksum As Long, ByRef errorCountFrame As Long, ByRef errorCountOverflow As Long)
Parameters:
  • brickletPort – Type: Char, Range: ["a"C to "b"C]
Output Parameters:
  • errorCountACKChecksum – Type: Long, Range: [0 to 232 - 1]
  • errorCountMessageChecksum – Type: Long, Range: [0 to 232 - 1]
  • errorCountFrame – Type: Long, Range: [0 to 232 - 1]
  • errorCountOverflow – Type: Long, Range: [0 to 232 - 1]

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.

New in version 2.3.3 (Firmware).

Sub BrickStepper.EnableStatusLED()

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.

New in version 2.3.1 (Firmware).

Sub BrickStepper.DisableStatusLED()

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.

New in version 2.3.1 (Firmware).

Function BrickStepper.IsStatusLEDEnabled() As Boolean
Returns:
  • enabled – Type: Boolean, Default: true

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

New in version 2.3.1 (Firmware).

Function BrickStepper.GetChipTemperature() As Short
Returns:
  • temperature – Type: Short, Unit: 1/10 °C, Range: [-215 to 215 - 1]

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.

Sub BrickStepper.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!

Sub BrickStepper.GetIdentity(ByRef uid As String, ByRef connectedUid As String, ByRef position As Char, ByRef hardwareVersion() As Byte, ByRef firmwareVersion() As Byte, ByRef deviceIdentifier As Integer)
Output Parameters:
  • uid – Type: String, Length: up to 8
  • connectedUid – Type: String, Length: up to 8
  • position – Type: Char, Range: ["0"C to "8"C]
  • hardwareVersion – Type: Byte Array, Length: 3
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • firmwareVersion – Type: Byte Array, Length: 3
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • deviceIdentifier – Type: Integer, Range: [0 to 216 - 1]

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. There is also a constant for the device identifier of this Brick.

Callback Configuration Functions

Sub BrickStepper.SetMinimumVoltage(ByVal voltage As Integer)
Parameters:
  • voltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1], Default: 8000

Sets the minimum voltage, below which the UnderVoltageCallback 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.

Function BrickStepper.GetMinimumVoltage() As Integer
Returns:
  • voltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1], Default: 8000

Returns the minimum voltage as set by SetMinimumVoltage().

Sub BrickStepper.SetAllDataPeriod(ByVal period As Long)
Parameters:
  • period – Type: Long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

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

Function BrickStepper.GetAllDataPeriod() As Long
Returns:
  • period – Type: Long, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by SetAllDataPeriod().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a procedure to an callback property of the device object:

Sub MyCallback(ByVal sender As BrickStepper, ByVal value As Short)
    Console.WriteLine("Value: {0}", value)
End Sub

AddHandler stepper.ExampleCallback, AddressOf MyCallback

The available callback property and their type of parameters are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

Event BrickStepper.UnderVoltageCallback(ByVal sender As BrickStepper, ByVal voltage As Integer)
Callback Parameters:
  • sender – Type: BrickStepper
  • voltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]

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

Event BrickStepper.PositionReachedCallback(ByVal sender As BrickStepper, ByVal position As Integer)
Callback Parameters:
  • sender – Type: BrickStepper
  • position – Type: Integer, Range: [-231 to 231 - 1]

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.

Event BrickStepper.AllDataCallback(ByVal sender As BrickStepper, ByVal currentVelocity As Integer, ByVal currentPosition As Integer, ByVal remainingSteps As Integer, ByVal stackVoltage As Integer, ByVal externalVoltage As Integer, ByVal currentConsumption As Integer)
Callback Parameters:
  • sender – Type: BrickStepper
  • currentVelocity – Type: Integer, Unit: 1 1/s, Range: [0 to 216 - 1]
  • currentPosition – Type: Integer, Range: [-231 to 231 - 1]
  • remainingSteps – Type: Integer, Range: [-231 to 231 - 1]
  • stackVoltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]
  • externalVoltage – Type: Integer, Unit: 1 mV, Range: [0 to 216 - 1]
  • currentConsumption – Type: Integer, Unit: 1 mA, Range: [0 to 216 - 1]

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.

Event BrickStepper.NewStateCallback(ByVal sender As BrickStepper, ByVal stateNew As Byte, ByVal statePrevious As Byte)
Callback Parameters:
  • sender – Type: BrickStepper
  • stateNew – Type: Byte, Range: See constants
  • statePrevious – Type: Byte, Range: See constants

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

The following constants are available for this function:

For stateNew:

  • BrickStepper.STATE_STOP = 1
  • BrickStepper.STATE_ACCELERATION = 2
  • BrickStepper.STATE_RUN = 3
  • BrickStepper.STATE_DEACCELERATION = 4
  • BrickStepper.STATE_DIRECTION_CHANGE_TO_FORWARD = 5
  • BrickStepper.STATE_DIRECTION_CHANGE_TO_BACKWARD = 6

For statePrevious:

  • BrickStepper.STATE_STOP = 1
  • BrickStepper.STATE_ACCELERATION = 2
  • BrickStepper.STATE_RUN = 3
  • BrickStepper.STATE_DEACCELERATION = 4
  • BrickStepper.STATE_DIRECTION_CHANGE_TO_FORWARD = 5
  • BrickStepper.STATE_DIRECTION_CHANGE_TO_BACKWARD = 6

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

Function BrickStepper.GetAPIVersion() As Byte()
Output Parameters:
  • apiVersion – Type: Byte Array, Length: 3
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]

Returns the version of the API definition 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.

Function BrickStepper.GetResponseExpected(ByVal functionId As Byte) As Boolean
Parameters:
  • functionId – Type: Byte, Range: See constants
Returns:
  • responseExpected – Type: Boolean

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.

The following constants are available for this function:

For functionId:

  • BrickStepper.FUNCTION_SET_MAX_VELOCITY = 1
  • BrickStepper.FUNCTION_SET_SPEED_RAMPING = 4
  • BrickStepper.FUNCTION_FULL_BRAKE = 6
  • BrickStepper.FUNCTION_SET_CURRENT_POSITION = 7
  • BrickStepper.FUNCTION_SET_TARGET_POSITION = 9
  • BrickStepper.FUNCTION_SET_STEPS = 11
  • BrickStepper.FUNCTION_SET_STEP_MODE = 14
  • BrickStepper.FUNCTION_DRIVE_FORWARD = 16
  • BrickStepper.FUNCTION_DRIVE_BACKWARD = 17
  • BrickStepper.FUNCTION_STOP = 18
  • BrickStepper.FUNCTION_SET_MOTOR_CURRENT = 22
  • BrickStepper.FUNCTION_ENABLE = 24
  • BrickStepper.FUNCTION_DISABLE = 25
  • BrickStepper.FUNCTION_SET_DECAY = 27
  • BrickStepper.FUNCTION_SET_MINIMUM_VOLTAGE = 29
  • BrickStepper.FUNCTION_SET_SYNC_RECT = 33
  • BrickStepper.FUNCTION_SET_TIME_BASE = 35
  • BrickStepper.FUNCTION_SET_ALL_DATA_PERIOD = 38
  • BrickStepper.FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
  • BrickStepper.FUNCTION_SET_SPITFP_BAUDRATE = 234
  • BrickStepper.FUNCTION_ENABLE_STATUS_LED = 238
  • BrickStepper.FUNCTION_DISABLE_STATUS_LED = 239
  • BrickStepper.FUNCTION_RESET = 243
  • BrickStepper.FUNCTION_WRITE_BRICKLET_PLUGIN = 246
Sub BrickStepper.SetResponseExpected(ByVal functionId As Byte, ByVal responseExpected As Boolean)
Parameters:
  • functionId – Type: Byte, Range: See constants
  • responseExpected – Type: Boolean

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.

The following constants are available for this function:

For functionId:

  • BrickStepper.FUNCTION_SET_MAX_VELOCITY = 1
  • BrickStepper.FUNCTION_SET_SPEED_RAMPING = 4
  • BrickStepper.FUNCTION_FULL_BRAKE = 6
  • BrickStepper.FUNCTION_SET_CURRENT_POSITION = 7
  • BrickStepper.FUNCTION_SET_TARGET_POSITION = 9
  • BrickStepper.FUNCTION_SET_STEPS = 11
  • BrickStepper.FUNCTION_SET_STEP_MODE = 14
  • BrickStepper.FUNCTION_DRIVE_FORWARD = 16
  • BrickStepper.FUNCTION_DRIVE_BACKWARD = 17
  • BrickStepper.FUNCTION_STOP = 18
  • BrickStepper.FUNCTION_SET_MOTOR_CURRENT = 22
  • BrickStepper.FUNCTION_ENABLE = 24
  • BrickStepper.FUNCTION_DISABLE = 25
  • BrickStepper.FUNCTION_SET_DECAY = 27
  • BrickStepper.FUNCTION_SET_MINIMUM_VOLTAGE = 29
  • BrickStepper.FUNCTION_SET_SYNC_RECT = 33
  • BrickStepper.FUNCTION_SET_TIME_BASE = 35
  • BrickStepper.FUNCTION_SET_ALL_DATA_PERIOD = 38
  • BrickStepper.FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
  • BrickStepper.FUNCTION_SET_SPITFP_BAUDRATE = 234
  • BrickStepper.FUNCTION_ENABLE_STATUS_LED = 238
  • BrickStepper.FUNCTION_DISABLE_STATUS_LED = 239
  • BrickStepper.FUNCTION_RESET = 243
  • BrickStepper.FUNCTION_WRITE_BRICKLET_PLUGIN = 246
Sub BrickStepper.SetResponseExpectedAll(ByVal responseExpected As Boolean)
Parameters:
  • responseExpected – Type: Boolean

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

Internal Functions

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

Sub BrickStepper.GetProtocol1BrickletName(ByVal port As Char, ByRef protocolVersion As Byte, ByRef firmwareVersion() As Byte, ByRef name As String)
Parameters:
  • port – Type: Char, Range: ["a"C to "b"C]
Output Parameters:
  • protocolVersion – Type: Byte, Range: [0 to 255]
  • firmwareVersion – Type: Byte Array, Length: 3
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • name – Type: String, Length: up to 40

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.

Sub BrickStepper.WriteBrickletPlugin(ByVal port As Char, ByVal offset As Byte, ByVal chunk() As Byte)
Parameters:
  • port – Type: Char, Range: ["a"C to "b"C]
  • offset – Type: Byte, Range: [0 to 255]
  • chunk – Type: Byte Array, Length: 32, Range: [0 to 255]

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.

Function BrickStepper.ReadBrickletPlugin(ByVal port As Char, ByVal offset As Byte) As Byte()
Parameters:
  • port – Type: Char, Range: ["a"C to "b"C]
  • offset – Type: Byte, Range: [0 to 255]
Returns:
  • chunk – Type: Byte Array, Length: 32, Range: [0 to 255]

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.

Constants

Const BrickStepper.DEVICE_IDENTIFIER

This constant is used to identify a Stepper Brick.

The GetIdentity() function and the IPConnection.EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

Const BrickStepper.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Stepper Brick.