C# - Accelerometer Bricklet 2.0

This is the description of the C# API bindings for the Accelerometer Bricklet 2.0. General information and technical specifications for the Accelerometer Bricklet 2.0 are summarized in its hardware description.

An installation guide for the C# API bindings is part of their general description.

Examples

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

Simple

Download (ExampleSimple.cs)

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using System;
using Tinkerforge;

class Example
{
    private static string HOST = "localhost";
    private static int PORT = 4223;
    private static string UID = "XYZ"; // Change XYZ to the UID of your Accelerometer Bricklet 2.0

    static void Main()
    {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletAccelerometerV2 a =
          new BrickletAccelerometerV2(UID, ipcon); // Create device object

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

        // Get current acceleration
        int x, y, z;
        a.GetAcceleration(out x, out y, out z);

        Console.WriteLine("Acceleration [X]: " + x/10000.0 + " g");
        Console.WriteLine("Acceleration [Y]: " + y/10000.0 + " g");
        Console.WriteLine("Acceleration [Z]: " + z/10000.0 + " g");

        Console.WriteLine("Press enter to exit");
        Console.ReadLine();
        ipcon.Disconnect();
    }
}

Callback

Download (ExampleCallback.cs)

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using System;
using Tinkerforge;

class Example
{
    private static string HOST = "localhost";
    private static int PORT = 4223;
    private static string UID = "XYZ"; // Change XYZ to the UID of your Accelerometer Bricklet 2.0

    // Callback function for acceleration callback
    static void AccelerationCB(BrickletAccelerometerV2 sender, int x, int y, int z)
    {
        Console.WriteLine("Acceleration [X]: " + x/10000.0 + " g");
        Console.WriteLine("Acceleration [Y]: " + y/10000.0 + " g");
        Console.WriteLine("Acceleration [Z]: " + z/10000.0 + " g");
        Console.WriteLine("");
    }

    static void Main()
    {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletAccelerometerV2 a =
          new BrickletAccelerometerV2(UID, ipcon); // Create device object

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

        // Register acceleration callback to function AccelerationCB
        a.AccelerationCallback += AccelerationCB;

        // Set period for acceleration callback to 1s (1000ms)
        a.SetAccelerationCallbackConfiguration(1000, false);

        Console.WriteLine("Press enter to exit");
        Console.ReadLine();
        ipcon.Disconnect();
    }
}

API

Generally, every method of the C# bindings that returns a value can throw a Tinkerforge.TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Since C# does not support multiple return values directly, we use the out keyword to return multiple values from a method.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

All methods listed below are thread-safe.

Basic Functions

public class BrickletAccelerometerV2(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid:

BrickletAccelerometerV2 accelerometerV2 = new BrickletAccelerometerV2("YOUR_DEVICE_UID", ipcon);

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

public void GetAcceleration(out int x, out int y, out int z)

Returns the acceleration in x, y and z direction. The values are given in g/10000 (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 SetAccelerationCallbackConfiguration().

public void SetConfiguration(byte dataRate, byte fullScale)

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

  • Data rate of 0.781Hz to 25600Hz.
  • Full scale range of -2g to +2g up to -8g to +8g.

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

The default values are 100Hz data rate and -2g to +2g range.

The following constants are available for this function:

  • BrickletAccelerometerV2.DATA_RATE_0_781HZ = 0
  • BrickletAccelerometerV2.DATA_RATE_1_563HZ = 1
  • BrickletAccelerometerV2.DATA_RATE_3_125HZ = 2
  • BrickletAccelerometerV2.DATA_RATE_6_2512HZ = 3
  • BrickletAccelerometerV2.DATA_RATE_12_5HZ = 4
  • BrickletAccelerometerV2.DATA_RATE_25HZ = 5
  • BrickletAccelerometerV2.DATA_RATE_50HZ = 6
  • BrickletAccelerometerV2.DATA_RATE_100HZ = 7
  • BrickletAccelerometerV2.DATA_RATE_200HZ = 8
  • BrickletAccelerometerV2.DATA_RATE_400HZ = 9
  • BrickletAccelerometerV2.DATA_RATE_800HZ = 10
  • BrickletAccelerometerV2.DATA_RATE_1600HZ = 11
  • BrickletAccelerometerV2.DATA_RATE_3200HZ = 12
  • BrickletAccelerometerV2.DATA_RATE_6400HZ = 13
  • BrickletAccelerometerV2.DATA_RATE_12800HZ = 14
  • BrickletAccelerometerV2.DATA_RATE_25600HZ = 15
  • BrickletAccelerometerV2.FULL_SCALE_2G = 0
  • BrickletAccelerometerV2.FULL_SCALE_4G = 1
  • BrickletAccelerometerV2.FULL_SCALE_8G = 2
public void GetConfiguration(out byte dataRate, out byte fullScale)

Returns the configuration as set by SetConfiguration().

The following constants are available for this function:

  • BrickletAccelerometerV2.DATA_RATE_0_781HZ = 0
  • BrickletAccelerometerV2.DATA_RATE_1_563HZ = 1
  • BrickletAccelerometerV2.DATA_RATE_3_125HZ = 2
  • BrickletAccelerometerV2.DATA_RATE_6_2512HZ = 3
  • BrickletAccelerometerV2.DATA_RATE_12_5HZ = 4
  • BrickletAccelerometerV2.DATA_RATE_25HZ = 5
  • BrickletAccelerometerV2.DATA_RATE_50HZ = 6
  • BrickletAccelerometerV2.DATA_RATE_100HZ = 7
  • BrickletAccelerometerV2.DATA_RATE_200HZ = 8
  • BrickletAccelerometerV2.DATA_RATE_400HZ = 9
  • BrickletAccelerometerV2.DATA_RATE_800HZ = 10
  • BrickletAccelerometerV2.DATA_RATE_1600HZ = 11
  • BrickletAccelerometerV2.DATA_RATE_3200HZ = 12
  • BrickletAccelerometerV2.DATA_RATE_6400HZ = 13
  • BrickletAccelerometerV2.DATA_RATE_12800HZ = 14
  • BrickletAccelerometerV2.DATA_RATE_25600HZ = 15
  • BrickletAccelerometerV2.FULL_SCALE_2G = 0
  • BrickletAccelerometerV2.FULL_SCALE_4G = 1
  • BrickletAccelerometerV2.FULL_SCALE_8G = 2
public void SetInfoLEDConfig(byte config)

Configures the info LED (marked as "Force" on the Bricklet) to be either turned off, turned on, or blink in heartbeat mode.

The following constants are available for this function:

  • BrickletAccelerometerV2.INFO_LED_CONFIG_OFF = 0
  • BrickletAccelerometerV2.INFO_LED_CONFIG_ON = 1
  • BrickletAccelerometerV2.INFO_LED_CONFIG_SHOW_HEARTBEAT = 2
public byte GetInfoLEDConfig()

Returns the LED configuration as set by SetInfoLEDConfig()

The following constants are available for this function:

  • BrickletAccelerometerV2.INFO_LED_CONFIG_OFF = 0
  • BrickletAccelerometerV2.INFO_LED_CONFIG_ON = 1
  • BrickletAccelerometerV2.INFO_LED_CONFIG_SHOW_HEARTBEAT = 2
public void SetContinuousAccelerationConfiguration(bool enableX, bool enableY, bool enableZ, byte resolution)

For high throughput of acceleration data (> 1000Hz) you have to use the ContinuousAcceleration16BitCallback or ContinuousAcceleration8BitCallback callbacks.

You can enable the callback for each axis (x, y, z) individually and choose a resolution of 8 bit or 16 bit.

If at least one of the axis is enabled and the resolution is set to 8 bit, the ContinuousAcceleration8BitCallback callback is activated. If at least one of the axis is enabled and the resolution is set to 16 bit, the ContinuousAcceleration16BitCallback callback is activated.

The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.

Otherwise you have to use the following formulas that depend on the configured resolution (8/16 bit) and the full scale range (see SetConfiguration()) to calculate the data in g/10000 (same unit that is returned by GetAcceleration()):

  • 16 bit, full scale 2G: acceleration = value*625/1024
  • 16 bit, full scale 4G: acceleration = value*1250/1024
  • 16 bit, full scale 8G: acceleration = value*2500/1024

If a resolution of 8 bit is used, only the 8 most significant bits will be transferred, so you can use the following formulas:

  • 8 bit, full scale 2G: acceleration = value*256*625/1024
  • 8 bit, full scale 4G: acceleration = value*256*1250/1024
  • 8 bit, full scale 8G: acceleration = value*256*2500/1024

If no axis is enabled, both callbacks are disabled. If one of the continuous callbacks is enabled, the AccelerationCallback callback is disabled.

The maximum throughput depends on the exact configuration:

Number of axis enabled Throughput 8 bit Throughout 16 bit
1 25600Hz 25600Hz
2 25600Hz 15000Hz
3 20000Hz 10000Hz

The following constants are available for this function:

  • BrickletAccelerometerV2.RESOLUTION_8BIT = 0
  • BrickletAccelerometerV2.RESOLUTION_16BIT = 1
public void GetContinuousAccelerationConfiguration(out bool enableX, out bool enableY, out bool enableZ, out byte resolution)

Returns the continuous acceleration configuration as set by SetContinuousAccelerationConfiguration().

The following constants are available for this function:

  • BrickletAccelerometerV2.RESOLUTION_8BIT = 0
  • BrickletAccelerometerV2.RESOLUTION_16BIT = 1

Advanced Functions

public void SetFilterConfiguration(byte iirBypass, byte lowPassFilter)

Configures IIR Bypass filter mode and low pass filter roll off corner frequency.

The filter can be applied or bypassed and the corner frequency can be half or a ninth of the output data rate.

Accelerometer filter

By default filtering is applied and the filter corner frequency is a ninth of the output data rate.

The following constants are available for this function:

  • BrickletAccelerometerV2.IIR_BYPASS_APPLIED = 0
  • BrickletAccelerometerV2.IIR_BYPASS_BYPASSED = 1
  • BrickletAccelerometerV2.LOW_PASS_FILTER_NINTH = 0
  • BrickletAccelerometerV2.LOW_PASS_FILTER_HALF = 1

New in version 2.0.2 (Plugin).

public void GetFilterConfiguration(out byte iirBypass, out byte lowPassFilter)

Returns the configuration as set by SetFilterConfiguration().

The following constants are available for this function:

  • BrickletAccelerometerV2.IIR_BYPASS_APPLIED = 0
  • BrickletAccelerometerV2.IIR_BYPASS_BYPASSED = 1
  • BrickletAccelerometerV2.LOW_PASS_FILTER_NINTH = 0
  • BrickletAccelerometerV2.LOW_PASS_FILTER_HALF = 1

New in version 2.0.2 (Plugin).

public byte[] GetAPIVersion()

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.

public bool GetResponseExpected(byte functionId)

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.

public void SetResponseExpected(byte functionId, bool responseExpected)

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:

  • BrickletAccelerometerV2.FUNCTION_SET_CONFIGURATION = 2
  • BrickletAccelerometerV2.FUNCTION_SET_ACCELERATION_CALLBACK_CONFIGURATION = 4
  • BrickletAccelerometerV2.FUNCTION_SET_INFO_LED_CONFIG = 6
  • BrickletAccelerometerV2.FUNCTION_SET_CONTINUOUS_ACCELERATION_CONFIGURATION = 9
  • BrickletAccelerometerV2.FUNCTION_SET_FILTER_CONFIGURATION = 13
  • BrickletAccelerometerV2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletAccelerometerV2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletAccelerometerV2.FUNCTION_RESET = 243
  • BrickletAccelerometerV2.FUNCTION_WRITE_UID = 248
public void SetResponseExpectedAll(bool responseExpected)

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

public void GetSPITFPErrorCount(out long errorCountAckChecksum, out long errorCountMessageChecksum, out long errorCountFrame, out long errorCountOverflow)

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 Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

public byte SetBootloaderMode(byte mode)

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

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

The following constants are available for this function:

  • BrickletAccelerometerV2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletAccelerometerV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_OK = 0
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletAccelerometerV2.BOOTLOADER_STATUS_CRC_MISMATCH = 5
public byte GetBootloaderMode()

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

  • BrickletAccelerometerV2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletAccelerometerV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletAccelerometerV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
public void SetWriteFirmwarePointer(long pointer)

Sets the firmware pointer for WriteFirmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

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

public byte WriteFirmware(byte[] data)

Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

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

public void SetStatusLEDConfig(byte config)

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

  • BrickletAccelerometerV2.STATUS_LED_CONFIG_OFF = 0
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_ON = 1
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public byte GetStatusLEDConfig()

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

  • BrickletAccelerometerV2.STATUS_LED_CONFIG_OFF = 0
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_ON = 1
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletAccelerometerV2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public short GetChipTemperature()

Returns the temperature in °C 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 bad accuracy. Practically it is only useful as an indicator for temperature changes.

public void Reset()

Calling this function will reset the Bricklet. All configurations will be lost.

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

public void WriteUID(long uid)

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

public long ReadUID()

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

public void GetIdentity(out string uid, out string connectedUid, out char position, out byte[] hardwareVersion, out byte[] firmwareVersion, out int deviceIdentifier)

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

public void SetAccelerationCallbackConfiguration(long period, bool valueHasToChange)

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

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

If this callback is enabled, the ContinuousAcceleration16BitCallback callback and ContinuousAcceleration8BitCallback callback will automatically be disabled.

The default value is (0, false).

public void GetAccelerationCallbackConfiguration(out long period, out bool valueHasToChange)

Returns the callback configuration as set by SetAccelerationCallbackConfiguration().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by appending your callback handler to the corresponding event:

void MyCallback(BrickletAccelerometerV2 sender, int value)
{
    System.Console.WriteLine("Value: " + value);
}

accelerometerV2.ExampleCallback += MyCallback;

The available events 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.

public event AccelerationCallback(BrickletAccelerometerV2 sender, int x, int y, int z)

This callback is triggered periodically according to the configuration set by SetAccelerationCallbackConfiguration().

The parameters are the same as GetAcceleration().

public event ContinuousAcceleration16BitCallback(BrickletAccelerometerV2 sender, short[] acceleration)

Returns 30 acceleration values with 16 bit resolution. The data rate can be configured with SetConfiguration() and this callback can be enabled with SetContinuousAccelerationConfiguration().

The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.

Otherwise you have to use the following formulas that depend on the full scale range (see SetConfiguration()) to calculate the data in g/10000 (same unit that is returned by GetAcceleration()):

  • Full scale 2G: acceleration = value*625/1024
  • Full scale 4G: acceleration = value*1250/1024
  • Full scale 8G: acceleration = value*2500/1024

The data is formated in the sequence "x, y, z, x, y, z, ..." depending on the enabled axis. Examples:

  • x, y, z enabled: "x, y, z, ... 10x ..., x, y, z"
  • x, z enabled: "x, z, ... 15x ..., x, z"
  • y enabled: "y, ... 30x ..., y"
public event ContinuousAcceleration8BitCallback(BrickletAccelerometerV2 sender, short[] acceleration)

Returns 30 acceleration values with 8 bit resolution. The data rate can be configured with SetConfiguration() and this callback can be enabled with SetContinuousAccelerationConfiguration().

The returned values are raw ADC data. If you want to put this data into a FFT to determine the occurrences of specific frequencies we recommend that you use the data as is. It has all of the ADC noise in it. This noise looks like pure noise at first glance, but it might still have some frequnecy information in it that can be utilized by the FFT.

Otherwise you have to use the following formulas that depend on the full scale range (see SetConfiguration()) to calculate the data in g/10000 (same unit that is returned by GetAcceleration()):

  • Full scale 2G: acceleration = value*256*625/1024
  • Full scale 4G: acceleration = value*256*1250/1024
  • Full scale 8G: acceleration = value*256*2500/1024

The data is formated in the sequence "x, y, z, x, y, z, ..." depending on the enabled axis. Examples:

  • x, y, z enabled: "x, y, z, ... 20x ..., x, y, z"
  • x, z enabled: "x, z, ... 30x ..., x, z"
  • y enabled: "y, ... 60x ..., y"

Constants

public int DEVICE_IDENTIFIER

This constant is used to identify a Accelerometer Bricklet 2.0.

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.

public string DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Accelerometer Bricklet 2.0.