LabVIEW - DC Brick¶

Configuration¶

Download (Example Configuration.vi)

Callback¶

Download (Example Callback.vi), Download (Example Callback - VelocityReached Callback.vi)

Basic Functions¶

BrickDC(uid, ipcon) → dc¶

Input:	uid – Type: String ipcon – Type: .NET Refnum (IPConnection)
Output:	dc – Type: .NET Refnum (BrickDC)

Creates an object with the unique device ID uid. This object can then be used after the IP Connection is connected.

BrickDC.SetVelocity(velocity)¶

Input:	velocity – Type: Int16, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0

Sets the velocity of the motor. Whereas -32767 is full speed backward, 0 is stop and 32767 is full speed forward. Depending on the acceleration (see SetAcceleration()), the motor is not immediately brought to the velocity but smoothly accelerated.

The velocity describes the duty cycle of the PWM with which the motor is controlled, e.g. a velocity of 3277 sets a PWM with a 10% duty cycle. You can not only control the duty cycle of the PWM but also the frequency, see SetPWMFrequency().

BrickDC.GetVelocity() → velocity¶

Output:	velocity – Type: Int16, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0

Returns the velocity as set by SetVelocity().

BrickDC.GetCurrentVelocity() → velocity¶

Output:	velocity – Type: Int16, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1], Default: 0

Returns the current velocity of the motor. This value is different from GetVelocity() whenever the motor is currently accelerating to a goal set by SetVelocity().

BrickDC.SetAcceleration(acceleration)¶

Input:	acceleration – Type: Int32, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000

Sets the acceleration of the motor. It is given in velocity/s. An acceleration of 10000 means, that every second the velocity is increased by 10000 (or about 30% duty cycle).

For example: If the current velocity is 0 and you want to accelerate to a velocity of 16000 (about 50% duty cycle) in 10 seconds, you should set an acceleration of 1600.

If acceleration is set to 0, there is no speed ramping, i.e. a new velocity is immediately given to the motor.

BrickDC.GetAcceleration() → acceleration¶

Output:	acceleration – Type: Int32, Unit: 100/32767 %/s, Range: [0 to 216 - 1], Default: 10000

Returns the acceleration as set by SetAcceleration().

BrickDC.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 SetVelocity() with 0 if you just want to stop the motor.

BrickDC.Enable()¶

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

BrickDC.Disable()¶

Disables the driver chip. The configurations are kept (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 SetVelocity() with 0 before disabling the motor power. The SetVelocity() function will not wait until the motor is actually stopped. You have to explicitly wait for the appropriate time after calling the SetVelocity() function before calling the Disable() function.

BrickDC.IsEnabled() → enabled¶

Output:	enabled – Type: Boolean, Default: F

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

Advanced Functions¶

BrickDC.SetPWMFrequency(frequency)¶

Input:	frequency – Type: Int32, Unit: 1 Hz, Range: [1 to 20000], Default: 15000

Sets the frequency of the PWM with which the motor is driven. Often a high frequency is less noisy and the motor runs smoother. However, with a low frequency there are less switches and therefore fewer switching losses. Also with most motors lower frequencies enable higher torque.

If you have no idea what all this means, just ignore this function and use the default frequency, it will very likely work fine.

BrickDC.GetPWMFrequency() → frequency¶

Output:	frequency – Type: Int32, Unit: 1 Hz, Range: [1 to 20000], Default: 15000

Returns the PWM frequency as set by SetPWMFrequency().

BrickDC.GetStackInputVoltage() → voltage¶

Output:	voltage – Type: Int32, 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.

BrickDC.GetExternalInputVoltage() → voltage¶

Output:	voltage – Type: Int32, 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 DC 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.

BrickDC.GetCurrentConsumption() → voltage¶

Output:	voltage – Type: Int32, Unit: 1 mA, Range: [0 to 216 - 1]

Returns the current consumption of the motor.

BrickDC.SetDriveMode(mode)¶

Input:	mode – Type: Byte, Range: See constants, Default: 0

Sets the drive mode. Possible modes are:

• 0 = Drive/Brake
• 1 = Drive/Coast

These modes are different kinds of motor controls.

In Drive/Brake mode, the motor is always either driving or braking. There is no freewheeling. Advantages are: A more linear correlation between PWM and velocity, more exact accelerations and the possibility to drive with slower velocities.

In Drive/Coast mode, the motor is always either driving or freewheeling. Advantages are: Less current consumption and less demands on the motor and driver chip.

The following constants are available for this function:

For mode:

• BrickDC.DRIVE_MODE_DRIVE_BRAKE = 0
• BrickDC.DRIVE_MODE_DRIVE_COAST = 1

BrickDC.GetDriveMode() → mode¶

Output:	mode – Type: Byte, Range: See constants, Default: 0

Returns the drive mode, as set by SetDriveMode().

The following constants are available for this function:

For mode:

• BrickDC.DRIVE_MODE_DRIVE_BRAKE = 0
• BrickDC.DRIVE_MODE_DRIVE_COAST = 1

BrickDC.SetSPITFPBaudrateConfig(enableDynamicBaudrate, minimumDynamicBaudrate)¶

Input:	enableDynamicBaudrate – Type: Boolean, Default: T minimumDynamicBaudrate – Type: Int64, 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 2.3.5 (Firmware).

BrickDC.GetSPITFPBaudrateConfig() → enableDynamicBaudrate, minimumDynamicBaudrate¶

Output:	enableDynamicBaudrate – Type: Boolean, Default: T minimumDynamicBaudrate – Type: Int64, Unit: 1 Bd, Range: [400000 to 2000000], Default: 400000

Returns the baudrate config, see SetSPITFPBaudrateConfig().

New in version 2.3.5 (Firmware).

BrickDC.GetSendTimeoutCount(communicationMethod) → timeoutCount¶

Input:	communicationMethod – Type: Byte, Range: See constants
Output:	timeoutCount – Type: Int64, 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:

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

New in version 2.3.3 (Firmware).

BrickDC.SetSPITFPBaudrate(brickletPort, baudrate)¶

Input:	brickletPort – Type: Char, Range: ["a" to "b"] baudrate – Type: Int64, 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).

BrickDC.GetSPITFPBaudrate(brickletPort) → baudrate¶

Input:	brickletPort – Type: Char, Range: ["a" to "b"]
Output:	baudrate – Type: Int64, 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).

BrickDC.GetSPITFPErrorCount(brickletPort) → errorCountACKChecksum, errorCountMessageChecksum, errorCountFrame, errorCountOverflow¶

Input:	brickletPort – Type: Char, Range: ["a" to "b"]
Output:	errorCountACKChecksum – Type: Int64, Range: [0 to 232 - 1] errorCountMessageChecksum – Type: Int64, Range: [0 to 232 - 1] errorCountFrame – Type: Int64, Range: [0 to 232 - 1] errorCountOverflow – Type: Int64, 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).

BrickDC.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).

BrickDC.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).

BrickDC.IsStatusLEDEnabled() → enabled¶

Output:	enabled – Type: Boolean, Default: T

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

New in version 2.3.1 (Firmware).

BrickDC.GetChipTemperature() → temperature¶

Output:	temperature – Type: Int16, 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.

BrickDC.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!

BrickDC.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier¶

Output:

uid – Type: String, Length: up to 8 connectedUid – Type: String, Length: up to 8 position – Type: Char, Range: ["0" to "8"] hardwareVersion – Type: Byte[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[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: Int32, 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¶

BrickDC.SetMinimumVoltage(voltage)¶

Input:	voltage – Type: Int32, Unit: 1 mV, Range: [0 to 216 - 1], Default: 6000

Sets the minimum voltage, below which the UnderVoltageCallback callback is triggered. The minimum possible value that works with the DC Brick is 6V. You can use this function to detect the discharge of a battery that is used to drive the motor. If you have a fixed power supply, you likely do not need this functionality.

BrickDC.GetMinimumVoltage() → voltage¶

Output:	voltage – Type: Int32, Unit: 1 mV, Range: [0 to 216 - 1], Default: 6000

Returns the minimum voltage as set by SetMinimumVoltage()

BrickDC.SetCurrentVelocityPeriod(period)¶

Input:	period – Type: Int32, Unit: 1 ms, Range: [0 to 216 - 1], Default: 0

Sets a period with which the CurrentVelocityCallback callback is triggered. A period of 0 turns the callback off.

BrickDC.GetCurrentVelocityPeriod() → period¶

Output:	period – Type: Int32, Unit: 1 ms, Range: [0 to 216 - 1], Default: 0

Returns the period as set by SetCurrentVelocityPeriod().

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a function to a callback property of the device object. The available callback property and their type of parameters are described below.

event BrickDC.UnderVoltageCallback → sender, voltage¶

Callback Output:	sender – Type: .NET Refnum (BrickDC) voltage – Type: Int32, 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 BrickDC.EmergencyShutdownCallback → sender¶

Callback Output:	sender – Type: .NET Refnum (BrickDC)

This callback is triggered if either the current consumption is too high (above 5A) or the temperature of the driver chip is too high (above 175°C). These two possibilities are essentially the same, since the temperature will reach this threshold immediately if the motor consumes too much current. In case of a voltage below 3.3V (external or stack) this callback is triggered as well.

If this callback is triggered, the driver chip gets disabled at the same time. That means, Enable() has to be called to drive the motor again.

Note

This callback only works in Drive/Brake mode (see SetDriveMode()). In Drive/Coast mode it is unfortunately impossible to reliably read the overcurrent/overtemperature signal from the driver chip.

event BrickDC.VelocityReachedCallback → sender, velocity¶

Callback Output:	sender – Type: .NET Refnum (BrickDC) velocity – Type: Int16, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1]

This callback is triggered whenever a set velocity is reached. For example: If a velocity of 0 is present, acceleration is set to 5000 and velocity to 10000, the VelocityReachedCallback callback will be triggered after about 2 seconds, when the set velocity is actually reached.

Note

Since we can't get any feedback from the DC motor, this only works if the acceleration (see SetAcceleration()) 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 BrickDC.CurrentVelocityCallback → sender, velocity¶

Callback Output:	sender – Type: .NET Refnum (BrickDC) velocity – Type: Int16, Unit: 100/32767 %, Range: [-215 + 1 to 215 - 1]

This callback is triggered with the period that is set by SetCurrentVelocityPeriod(). The parameter is the current velocity used by the motor.

The CurrentVelocityCallback callback is only triggered after the set period if there is a change in the velocity.

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.

BrickDC.GetAPIVersion() → apiVersion¶

Output:	apiVersion – Type: Byte[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.

BrickDC.GetResponseExpected(functionId) → responseExpected¶

Input:	functionId – Type: Byte, Range: See constants
Output:	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:

• BrickDC.FUNCTION_SET_VELOCITY = 1
• BrickDC.FUNCTION_SET_ACCELERATION = 4
• BrickDC.FUNCTION_SET_PWM_FREQUENCY = 6
• BrickDC.FUNCTION_FULL_BRAKE = 8
• BrickDC.FUNCTION_ENABLE = 12
• BrickDC.FUNCTION_DISABLE = 13
• BrickDC.FUNCTION_SET_MINIMUM_VOLTAGE = 15
• BrickDC.FUNCTION_SET_DRIVE_MODE = 17
• BrickDC.FUNCTION_SET_CURRENT_VELOCITY_PERIOD = 19
• BrickDC.FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
• BrickDC.FUNCTION_SET_SPITFP_BAUDRATE = 234
• BrickDC.FUNCTION_ENABLE_STATUS_LED = 238
• BrickDC.FUNCTION_DISABLE_STATUS_LED = 239
• BrickDC.FUNCTION_RESET = 243
• BrickDC.FUNCTION_WRITE_BRICKLET_PLUGIN = 246

BrickDC.SetResponseExpected(functionId, responseExpected)¶

Input:	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:

• BrickDC.FUNCTION_SET_VELOCITY = 1
• BrickDC.FUNCTION_SET_ACCELERATION = 4
• BrickDC.FUNCTION_SET_PWM_FREQUENCY = 6
• BrickDC.FUNCTION_FULL_BRAKE = 8
• BrickDC.FUNCTION_ENABLE = 12
• BrickDC.FUNCTION_DISABLE = 13
• BrickDC.FUNCTION_SET_MINIMUM_VOLTAGE = 15
• BrickDC.FUNCTION_SET_DRIVE_MODE = 17
• BrickDC.FUNCTION_SET_CURRENT_VELOCITY_PERIOD = 19
• BrickDC.FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
• BrickDC.FUNCTION_SET_SPITFP_BAUDRATE = 234
• BrickDC.FUNCTION_ENABLE_STATUS_LED = 238
• BrickDC.FUNCTION_DISABLE_STATUS_LED = 239
• BrickDC.FUNCTION_RESET = 243
• BrickDC.FUNCTION_WRITE_BRICKLET_PLUGIN = 246

BrickDC.SetResponseExpectedAll(responseExpected)¶

Input:	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.

BrickDC.GetProtocol1BrickletName(port) → protocolVersion, firmwareVersion, name¶

Input:	port – Type: Char, Range: ["a" to "b"]
Output:	protocolVersion – Type: Byte, Range: [0 to 255] firmwareVersion – Type: Byte[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.

BrickDC.WriteBrickletPlugin(port, offset, chunk)¶

Input:	port – Type: Char, Range: ["a" to "b"] offset – Type: Byte, Range: [0 to 255] chunk – Type: Byte[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.

BrickDC.ReadBrickletPlugin(port, offset) → chunk¶

Input:	port – Type: Char, Range: ["a" to "b"] offset – Type: Byte, Range: [0 to 255]
Output:	chunk – Type: Byte[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¶

BrickDC.DEVICE_IDENTIFIER¶

This constant is used to identify a DC 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.

BrickDC.DEVICE_DISPLAY_NAME¶

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