Visual Basic .NET - Accelerometer Bricklet

This is the description of the Visual Basic .NET API bindings for the Accelerometer Bricklet. General information and technical specifications for the Accelerometer Bricklet 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).

Simple

Download (ExampleSimple.vb)

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Imports System
Imports Tinkerforge

Module ExampleSimple
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XYZ" ' Change XYZ to the UID of your Accelerometer Bricklet

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

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

        ' Get current acceleration
        Dim x, y, z As Short

        a.GetAcceleration(x, y, z)

        Console.WriteLine("Acceleration [X]: " + (x/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Y]: " + (y/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Z]: " + (z/1000.0).ToString() + " g")

        Console.WriteLine("Press key to exit")
        Console.ReadLine()
        ipcon.Disconnect()
    End Sub
End Module

Callback

Download (ExampleCallback.vb)

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Imports System
Imports Tinkerforge

Module ExampleCallback
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XYZ" ' Change XYZ to the UID of your Accelerometer Bricklet

    ' Callback subroutine for acceleration callback
    Sub AccelerationCB(ByVal sender As BrickletAccelerometer, ByVal x As Short, _
                       ByVal y As Short, ByVal z As Short)
        Console.WriteLine("Acceleration [X]: " + (x/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Y]: " + (y/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Z]: " + (z/1000.0).ToString() + " g")
        Console.WriteLine("")
    End Sub

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

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

        ' Register acceleration callback to subroutine AccelerationCB
        AddHandler a.AccelerationCallback, AddressOf AccelerationCB

        ' Set period for acceleration callback to 1s (1000ms)
        ' Note: The acceleration callback is only called every second
        '       if the acceleration has changed since the last call!
        a.SetAccelerationCallbackPeriod(1000)

        Console.WriteLine("Press key to exit")
        Console.ReadLine()
        ipcon.Disconnect()
    End Sub
End Module

Threshold

Download (ExampleThreshold.vb)

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Imports System
Imports Tinkerforge

Module ExampleThreshold
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XYZ" ' Change XYZ to the UID of your Accelerometer Bricklet

    ' Callback subroutine for acceleration reached callback
    Sub AccelerationReachedCB(ByVal sender As BrickletAccelerometer, ByVal x As Short, _
                              ByVal y As Short, ByVal z As Short)
        Console.WriteLine("Acceleration [X]: " + (x/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Y]: " + (y/1000.0).ToString() + " g")
        Console.WriteLine("Acceleration [Z]: " + (z/1000.0).ToString() + " g")
        Console.WriteLine("")
    End Sub

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

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

        ' Get threshold callbacks with a debounce time of 10 seconds (10000ms)
        a.SetDebouncePeriod(10000)

        ' Register acceleration reached callback to subroutine AccelerationReachedCB
        AddHandler a.AccelerationReachedCallback, AddressOf AccelerationReachedCB

        ' Configure threshold for acceleration "greater than 2 g, 2 g, 2 g"
        a.SetAccelerationCallbackThreshold(">"C, 2*1000, 0, 2*1000, 0, 2*1000, 0)

        Console.WriteLine("Press key to exit")
        Console.ReadLine()
        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 BrickletAccelerometer(ByVal uid As String, ByVal ipcon As IPConnection)

Creates an object with the unique device ID uid:

Dim accelerometer As New BrickletAccelerometer("YOUR_DEVICE_UID", ipcon)

This object can then be used after the IP Connection is connected (see examples above).

Sub BrickletAccelerometer.GetAcceleration(ByRef x As Short, ByRef y As Short, ByRef z As Short)

Returns the acceleration in x, y and z direction. The values are given in g/1000 (1g = 9.80665m/s²), not to be confused with grams.

If you want to get the acceleration periodically, it is recommended to use the AccelerationCallback callback and set the period with SetAccelerationCallbackPeriod().

Function BrickletAccelerometer.GetTemperature() As Short

Returns the temperature of the accelerometer in °C.

Sub BrickletAccelerometer.LEDOn()

Enables the LED on the Bricklet.

Sub BrickletAccelerometer.LEDOff()

Disables the LED on the Bricklet.

Function BrickletAccelerometer.IsLEDOn() As Boolean

Returns true if the LED is enabled, false otherwise.

Advanced Functions

Sub BrickletAccelerometer.SetConfiguration(ByVal dataRate As Byte, ByVal fullScale As Byte, ByVal filterBandwidth As Byte)

Configures the data rate, full scale range and filter bandwidth. Possible values are:

  • Data rate of 0Hz to 1600Hz.
  • Full scale range of -2G to +2G up to -16G to +16G.
  • Filter bandwidth between 50Hz and 800Hz.

Decreasing data rate or full scale range will also decrease the noise on the data.

The default values are 100Hz data rate, -4G to +4G range and 200Hz filter bandwidth.

The following constants are available for this function:

  • BrickletAccelerometer.DATA_RATE_OFF = 0
  • BrickletAccelerometer.DATA_RATE_3HZ = 1
  • BrickletAccelerometer.DATA_RATE_6HZ = 2
  • BrickletAccelerometer.DATA_RATE_12HZ = 3
  • BrickletAccelerometer.DATA_RATE_25HZ = 4
  • BrickletAccelerometer.DATA_RATE_50HZ = 5
  • BrickletAccelerometer.DATA_RATE_100HZ = 6
  • BrickletAccelerometer.DATA_RATE_400HZ = 7
  • BrickletAccelerometer.DATA_RATE_800HZ = 8
  • BrickletAccelerometer.DATA_RATE_1600HZ = 9
  • BrickletAccelerometer.FULL_SCALE_2G = 0
  • BrickletAccelerometer.FULL_SCALE_4G = 1
  • BrickletAccelerometer.FULL_SCALE_6G = 2
  • BrickletAccelerometer.FULL_SCALE_8G = 3
  • BrickletAccelerometer.FULL_SCALE_16G = 4
  • BrickletAccelerometer.FILTER_BANDWIDTH_800HZ = 0
  • BrickletAccelerometer.FILTER_BANDWIDTH_400HZ = 1
  • BrickletAccelerometer.FILTER_BANDWIDTH_200HZ = 2
  • BrickletAccelerometer.FILTER_BANDWIDTH_50HZ = 3
Sub BrickletAccelerometer.GetConfiguration(ByRef dataRate As Byte, ByRef fullScale As Byte, ByRef filterBandwidth As Byte)

Returns the configuration as set by SetConfiguration().

The following constants are available for this function:

  • BrickletAccelerometer.DATA_RATE_OFF = 0
  • BrickletAccelerometer.DATA_RATE_3HZ = 1
  • BrickletAccelerometer.DATA_RATE_6HZ = 2
  • BrickletAccelerometer.DATA_RATE_12HZ = 3
  • BrickletAccelerometer.DATA_RATE_25HZ = 4
  • BrickletAccelerometer.DATA_RATE_50HZ = 5
  • BrickletAccelerometer.DATA_RATE_100HZ = 6
  • BrickletAccelerometer.DATA_RATE_400HZ = 7
  • BrickletAccelerometer.DATA_RATE_800HZ = 8
  • BrickletAccelerometer.DATA_RATE_1600HZ = 9
  • BrickletAccelerometer.FULL_SCALE_2G = 0
  • BrickletAccelerometer.FULL_SCALE_4G = 1
  • BrickletAccelerometer.FULL_SCALE_6G = 2
  • BrickletAccelerometer.FULL_SCALE_8G = 3
  • BrickletAccelerometer.FULL_SCALE_16G = 4
  • BrickletAccelerometer.FILTER_BANDWIDTH_800HZ = 0
  • BrickletAccelerometer.FILTER_BANDWIDTH_400HZ = 1
  • BrickletAccelerometer.FILTER_BANDWIDTH_200HZ = 2
  • BrickletAccelerometer.FILTER_BANDWIDTH_50HZ = 3
Function BrickletAccelerometer.GetAPIVersion() As Byte()

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.

Function BrickletAccelerometer.GetResponseExpected(ByVal functionId As Byte) As 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 send and errors are silently ignored, because they cannot be detected.

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

Sub BrickletAccelerometer.SetResponseExpected(ByVal functionId As Byte, ByVal responseExpected As 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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletAccelerometer.FUNCTION_SET_ACCELERATION_CALLBACK_PERIOD = 2
  • BrickletAccelerometer.FUNCTION_SET_ACCELERATION_CALLBACK_THRESHOLD = 4
  • BrickletAccelerometer.FUNCTION_SET_DEBOUNCE_PERIOD = 6
  • BrickletAccelerometer.FUNCTION_SET_CONFIGURATION = 9
  • BrickletAccelerometer.FUNCTION_LED_ON = 11
  • BrickletAccelerometer.FUNCTION_LED_OFF = 12
Sub BrickletAccelerometer.SetResponseExpectedAll(ByVal responseExpected As Boolean)

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

Sub BrickletAccelerometer.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)

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

The position can be 'a', 'b', 'c' or 'd'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

Sub BrickletAccelerometer.SetAccelerationCallbackPeriod(ByVal period As Long)

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

The AccelerationCallback callback is only triggered if the acceleration has changed since the last triggering.

The default value is 0.

Function BrickletAccelerometer.GetAccelerationCallbackPeriod() As Long

Returns the period as set by SetAccelerationCallbackPeriod().

Sub BrickletAccelerometer.SetAccelerationCallbackThreshold(ByVal option As Char, ByVal minX As Short, ByVal maxX As Short, ByVal minY As Short, ByVal maxY As Short, ByVal minZ As Short, ByVal maxZ As Short)

Sets the thresholds for the AccelerationReachedCallback callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the acceleration is outside the min and max values
'i' Callback is triggered when the acceleration is inside the min and max values
'<' Callback is triggered when the acceleration is smaller than the min value (max is ignored)
'>' Callback is triggered when the acceleration is greater than the min value (max is ignored)

The default value is ('x', 0, 0, 0, 0, 0, 0).

The following constants are available for this function:

  • BrickletAccelerometer.THRESHOLD_OPTION_OFF = "x"C
  • BrickletAccelerometer.THRESHOLD_OPTION_OUTSIDE = "o"C
  • BrickletAccelerometer.THRESHOLD_OPTION_INSIDE = "i"C
  • BrickletAccelerometer.THRESHOLD_OPTION_SMALLER = "<"C
  • BrickletAccelerometer.THRESHOLD_OPTION_GREATER = ">"C
Sub BrickletAccelerometer.GetAccelerationCallbackThreshold(ByRef option As Char, ByRef minX As Short, ByRef maxX As Short, ByRef minY As Short, ByRef maxY As Short, ByRef minZ As Short, ByRef maxZ As Short)

Returns the threshold as set by SetAccelerationCallbackThreshold().

The following constants are available for this function:

  • BrickletAccelerometer.THRESHOLD_OPTION_OFF = "x"C
  • BrickletAccelerometer.THRESHOLD_OPTION_OUTSIDE = "o"C
  • BrickletAccelerometer.THRESHOLD_OPTION_INSIDE = "i"C
  • BrickletAccelerometer.THRESHOLD_OPTION_SMALLER = "<"C
  • BrickletAccelerometer.THRESHOLD_OPTION_GREATER = ">"C
Sub BrickletAccelerometer.SetDebouncePeriod(ByVal debounce As Long)

Sets the period in ms with which the threshold callback

is triggered, if the threshold

keeps being reached.

The default value is 100.

Function BrickletAccelerometer.GetDebouncePeriod() As Long

Returns the debounce period as set by SetDebouncePeriod().

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

AddHandler accelerometer.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 BrickletAccelerometer.AccelerationCallback(ByVal sender As BrickletAccelerometer, ByVal x As Short, ByVal y As Short, ByVal z As Short)

This callback is triggered periodically with the period that is set by SetAccelerationCallbackPeriod(). The parameters are the X, Y and Z acceleration.

The AccelerationCallback callback is only triggered if the acceleration has changed since the last triggering.

Event BrickletAccelerometer.AccelerationReachedCallback(ByVal sender As BrickletAccelerometer, ByVal x As Short, ByVal y As Short, ByVal z As Short)

This callback is triggered when the threshold as set by SetAccelerationCallbackThreshold() is reached. The parameters are the X, Y and Z acceleration.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().

Constants

Const BrickletAccelerometer.DEVICE_IDENTIFIER

This constant is used to identify a Accelerometer Bricklet.

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

Const BrickletAccelerometer.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Accelerometer Bricklet.