Software / API Bindings / MATLAB/Octave / API Reference and Examples / Bricklets / Servo Bricklet 2.0

MATLAB/Octave - Servo Bricklet 2.0¶

This is the description of the MATLAB/Octave API bindings for the Servo Bricklet 2.0. General information and technical specifications for the Servo Bricklet 2.0 are summarized in its hardware description.

An installation guide for the MATLAB/Octave API bindings is part of their general description.

Examples¶

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

Configuration (MATLAB)¶

Download (matlab_example_configuration.m)

function matlab_example_configuration()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletServoV2;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Servo Bricklet 2.0

    ipcon = IPConnection(); % Create IP connection
    s = handle(BrickletServoV2(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Servo 1: Connected to port 0, period of 19.5ms, pulse width of 1 to 2ms
    %          and operating angle -100 to 100°
    s.setDegree(0, -10000, 10000);
    s.setPulseWidth(0, 1000, 2000);
    s.setPeriod(0, 19500);
    s.setMotionConfiguration(0, 500000, 1000, ...
                             1000); % Full velocity with slow ac-/deceleration


    % Servo 2: Connected to port 5, period of 20ms, pulse width of 0.95 to 1.95ms
    %          and operating angle -90 to 90°
    s.setDegree(5, -9000, 9000);
    s.setPulseWidth(5, 950, 1950);
    s.setPeriod(5, 20000);
    s.setMotionConfiguration(5, 500000, 500000, ...
                             500000); % Full velocity with full ac-/deceleration

    s.setPosition(0, 10000); % Set to most right position
    s.setEnable(0, true);

    s.setPosition(5, -9000); % Set to most left position
    s.setEnable(5, true);

    input('Press key to exit\n', 's');

    s.setEnable(0, false);
    s.setEnable(5, false);

    ipcon.disconnect();
end

Callback (MATLAB)¶

Download (matlab_example_callback.m)

function matlab_example_callback()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletServoV2;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Servo Bricklet 2.0

    ipcon = IPConnection(); % Create IP connection
    s = handle(BrickletServoV2(UID, ipcon), 'CallbackProperties'); % Create device object

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

    % Register position reached callback to function cb_position_reached
    set(s, 'PositionReachedCallback', @(h, e) cb_position_reached(e));

    % Enable position reached callback
    s.setPositionReachedCallbackConfiguration(0, true);

    % Set velocity to 100°/s. This has to be smaller or equal to the
    % maximum velocity of the servo you are using, otherwise the position
    % reached callback will be called too early
    s.setMotionConfiguration(0, 10000, 500000, 500000);
    s.setPosition(0, 9000);
    s.setEnable(0, true);

    input('Press key to exit\n', 's');

    s.setEnable(0, false);

    ipcon.disconnect();
end

% Use position reached callback to swing back and forth
function cb_position_reached(e)
    s = e.getSource();

    if e.position == 9000
        fprintf('Position: 90°, going to -90°\n');
        s.setPosition(e.servoChannel, -9000);
    elseif e.position == -9000
        fprintf('Position: -90°, going to 90°\n');
        s.setPosition(e.servoChannel, 9000);
    else
        fprintf('Error\n'); % Can only happen if another program sets position
    end
end

Configuration (Octave)¶

Download (octave_example_configuration.m)

function octave_example_configuration()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Servo Bricklet 2.0

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    s = javaObject("com.tinkerforge.BrickletServoV2", UID, ipcon); % Create device object

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

    % Servo 1: Connected to port 0, period of 19.5ms, pulse width of 1 to 2ms
    %          and operating angle -100 to 100°
    s.setDegree(0, -10000, 10000);
    s.setPulseWidth(0, 1000, 2000);
    s.setPeriod(0, 19500);
    s.setMotionConfiguration(0, 500000, 1000, ...
                             1000); % Full velocity with slow ac-/deceleration


    % Servo 2: Connected to port 5, period of 20ms, pulse width of 0.95 to 1.95ms
    %          and operating angle -90 to 90°
    s.setDegree(5, -9000, 9000);
    s.setPulseWidth(5, 950, 1950);
    s.setPeriod(5, 20000);
    s.setMotionConfiguration(5, 500000, 500000, ...
                             500000); % Full velocity with full ac-/deceleration

    s.setPosition(0, 10000); % Set to most right position
    s.setEnable(0, true);

    s.setPosition(5, -9000); % Set to most left position
    s.setEnable(5, true);

    input("Press key to exit\n", "s");

    s.setEnable(0, false);
    s.setEnable(5, false);

    ipcon.disconnect();
end

Callback (Octave)¶

Download (octave_example_callback.m)

function octave_example_callback()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Servo Bricklet 2.0

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    s = javaObject("com.tinkerforge.BrickletServoV2", 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 function cb_position_reached
    s.addPositionReachedCallback(@cb_position_reached);

    % Enable position reached callback
    s.setPositionReachedCallbackConfiguration(0, true);

    % Set velocity to 100°/s. This has to be smaller or equal to the
    % maximum velocity of the servo you are using, otherwise the position
    % reached callback will be called too early
    s.setMotionConfiguration(0, 10000, 500000, 500000);
    s.setPosition(0, 9000);
    s.setEnable(0, true);

    input("Press key to exit\n", "s");

    s.setEnable(0, false);

    ipcon.disconnect();
end

% Use position reached callback to swing back and forth
function cb_position_reached(e)
    s = e.getSource();
    position = java2int(e.position);

    if position == 9000
        fprintf("Position: 90°, going to -90°\n");
        s.setPosition(java2int(e.servoChannel), -9000);
    elseif position == -9000
        fprintf("Position: -90°, going to 90°\n");
        s.setPosition(java2int(e.servoChannel), 9000);
    else
        fprintf("Error\n"); % Can only happen if another program sets position
    end
end

function int = java2int(value)
    if compare_versions(version(), "3.8", "<=")
        int = value.intValue();
    else
        int = value;
    end
end

API¶

Generally, every method of the MATLAB bindings that returns a value can throw a 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 unplugs the device). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Beside the TimeoutException there is also a NotConnectedException that is thrown if a method needs to communicate with the device while the IP Connection is not connected.

Since the MATLAB bindings are based on Java and Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.

The package for all Brick/Bricklet bindings and the IP Connection is com.tinkerforge.*

All methods listed below are thread-safe.

Every function of the Servo Brick API that has a servo_channel parameter can address a servo with the servo channel (0 to 9). If it is a setter function then multiple servos can be addressed at once with a bitmask for the servos, if the highest bit is set. For example: 1 will address servo 1, (1 << 1) | (1 << 5) | (1 << 15) will address servos 1 and 5. This allows to set configurations to several servos with one function call. It is guaranteed that the changes will take effect in the same PWM period for all servos you specified in the bitmask.

Basic Functions¶

class BrickletServoV2(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	servoV2 – Type: BrickletServoV2

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletServoV2;

servoV2 = BrickletServoV2('YOUR_DEVICE_UID', ipcon);

In Octave:

servoV2 = java_new("com.tinkerforge.BrickletServoV2", "YOUR_DEVICE_UID", ipcon);

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

BrickletServoV2.Status BrickletServoV2.getStatus()¶

Return Object:	enabled – Type: boolean[], Length: 10 currentPosition – Type: int[], Length: 10, Unit: 1/100 °, Range: ? currentVelocity – Type: int[], Length: 10, Unit: 1/100 °/s, Range: [0 to 500000] current – Type: int[], Length: 10, Unit: 1 mA, Range: [0 to 2¹⁶ - 1] inputVoltage – Type: int, Unit: 1 mV, Range: [0 to 2¹⁶ - 1]

Returns the status information of the Servo Bricklet 2.0.

The status includes

for each channel if it is enabled or disabled,
for each channel the current position,
for each channel the current velocity,
for each channel the current usage and
the input voltage.

Please note that the position and the velocity is a snapshot of the current position and velocity of the servo in motion.

void BrickletServoV2.setEnable(int servoChannel, boolean enable)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] enable – Type: boolean, Default: false

Enables a servo channel (0 to 9). If a servo is enabled, the configured position, velocity, acceleration, etc. are applied immediately.

boolean BrickletServoV2.getEnabled(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	enable – Type: boolean, Default: false

Returns true if the specified servo channel is enabled, false otherwise.

void BrickletServoV2.setPosition(int servoChannel, int position)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] position – Type: int, Unit: 1/100 °, Range: ?

Sets the position in °/100 for the specified servo channel.

The default range of the position is -9000 to 9000, but it can be specified according to your servo with setDegree().

If you want to control a linear servo or RC brushless motor controller or similar with the Servo Brick, you can also define lengths or speeds with setDegree().

int BrickletServoV2.getPosition(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	position – Type: int, Unit: 1/100 °, Range: ?

Returns the position of the specified servo channel as set by setPosition().

int BrickletServoV2.getCurrentPosition(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	position – Type: int, Unit: 1/100 °, Range: ?

Returns the current position of the specified servo channel. This may not be the value of setPosition() if the servo is currently approaching a position goal.

int BrickletServoV2.getCurrentVelocity(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	velocity – Type: int, Unit: 1/100 °/s, Range: [0 to 500000]

Returns the current velocity of the specified servo channel. This may not be the velocity specified by setMotionConfiguration(). if the servo is currently approaching a velocity goal.

void BrickletServoV2.setMotionConfiguration(int servoChannel, long velocity, long acceleration, long deceleration)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] velocity – Type: long, Unit: 1/100 °/s, Range: [0 to 500000], Default: 100000 acceleration – Type: long, Unit: 1/100 °/s², Range: [0 to 500000], Default: 50000 deceleration – Type: long, Unit: 1/100 °/s², Range: [0 to 500000], Default: 50000

Sets the maximum velocity of the specified servo channel in °/100s as well as the acceleration and deceleration in °/100s²

With a velocity of 0 °/100s the position will be set immediately (no velocity).

With an acc-/deceleration of 0 °/100s² the velocity will be set immediately (no acc-/deceleration).

BrickletServoV2.MotionConfiguration BrickletServoV2.getMotionConfiguration(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Return Object:	velocity – Type: long, Unit: 1/100 °/s, Range: [0 to 500000], Default: 100000 acceleration – Type: long, Unit: 1/100 °/s², Range: [0 to 500000], Default: 50000 deceleration – Type: long, Unit: 1/100 °/s², Range: [0 to 500000], Default: 50000

Returns the motion configuration as set by setMotionConfiguration().

void BrickletServoV2.setPulseWidth(int servoChannel, long min, long max)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] min – Type: long, Unit: 1 µs, Range: [0 to 2³² - 1], Default: 1000 max – Type: long, Unit: 1 µs, Range: [0 to 2³² - 1], Default: 2000

Sets the minimum and maximum pulse width of the specified servo channel in µs.

Usually, servos are controlled with a PWM, whereby the length of the pulse controls the position of the servo. Every servo has different minimum and maximum pulse widths, these can be specified with this function.

If you have a datasheet for your servo that specifies the minimum and maximum pulse width, you should set the values accordingly. If your servo comes without any datasheet you have to find the values via trial and error.

Both values have a range from 1 to 65535 (unsigned 16-bit integer). The minimum must be smaller than the maximum.

The default values are 1000µs (1ms) and 2000µs (2ms) for minimum and maximum pulse width.

BrickletServoV2.PulseWidth BrickletServoV2.getPulseWidth(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Return Object:	min – Type: long, Unit: 1 µs, Range: [0 to 2³² - 1], Default: 1000 max – Type: long, Unit: 1 µs, Range: [0 to 2³² - 1], Default: 2000

Returns the minimum and maximum pulse width for the specified servo channel as set by setPulseWidth().

void BrickletServoV2.setDegree(int servoChannel, int min, int max)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] min – Type: int, Unit: 1/100 °, Range: [-2¹⁵ to 2¹⁵ - 1], Default: -9000 max – Type: int, Unit: 1/100 °, Range: [-2¹⁵ to 2¹⁵ - 1], Default: 9000

Sets the minimum and maximum degree for the specified servo channel (by default given as °/100).

This only specifies the abstract values between which the minimum and maximum pulse width is scaled. For example: If you specify a pulse width of 1000µs to 2000µs and a degree range of -90° to 90°, a call of setPosition() with 0 will result in a pulse width of 1500µs (-90° = 1000µs, 90° = 2000µs, etc.).

Possible usage:

The datasheet of your servo specifies a range of 200° with the middle position at 110°. In this case you can set the minimum to -9000 and the maximum to 11000.
You measure a range of 220° on your servo and you don't have or need a middle position. In this case you can set the minimum to 0 and the maximum to 22000.
You have a linear servo with a drive length of 20cm, In this case you could set the minimum to 0 and the maximum to 20000. Now you can set the Position with setPosition() with a resolution of cm/100. Also the velocity will have a resolution of cm/100s and the acceleration will have a resolution of cm/100s².
You don't care about units and just want the highest possible resolution. In this case you should set the minimum to -32767 and the maximum to 32767.
You have a brushless motor with a maximum speed of 10000 rpm and want to control it with a RC brushless motor controller. In this case you can set the minimum to 0 and the maximum to 10000. setPosition() now controls the rpm.

Both values have a possible range from -32767 to 32767 (signed 16-bit integer). The minimum must be smaller than the maximum.

The default values are -9000 and 9000 for the minimum and maximum degree.

BrickletServoV2.Degree BrickletServoV2.getDegree(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Return Object:	min – Type: int, Unit: 1/100 °, Range: [-2¹⁵ to 2¹⁵ - 1], Default: -9000 max – Type: int, Unit: 1/100 °, Range: [-2¹⁵ to 2¹⁵ - 1], Default: 9000

Returns the minimum and maximum degree for the specified servo channel as set by setDegree().

void BrickletServoV2.setPeriod(int servoChannel, long period)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] period – Type: long, Unit: 1 µs, Range: [1 to 1000000], Default: 19500

Sets the period of the specified servo channel in µs.

Usually, servos are controlled with a PWM. Different servos expect PWMs with different periods. Most servos run well with a period of about 20ms.

If your servo comes with a datasheet that specifies a period, you should set it accordingly. If you don't have a datasheet and you have no idea what the correct period is, the default value (19.5ms) will most likely work fine.

The minimum possible period is 1µs and the maximum is 1000000µs.

The default value is 19.5ms (19500µs).

long BrickletServoV2.getPeriod(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	period – Type: long, Unit: 1 µs, Range: [1 to 1000000], Default: 19500

Returns the period for the specified servo channel as set by setPeriod().

int BrickletServoV2.getServoCurrent(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	current – Type: int, Unit: 1 mA, Range: [0 to 2¹⁶ - 1]

Returns the current consumption of the specified servo channel in mA.

void BrickletServoV2.setServoCurrentConfiguration(int servoChannel, int averagingDuration)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] averagingDuration – Type: int, Unit: 1 ms, Range: [1 to 255], Default: 255

Sets the averaging duration of the current measurement for the specified servo channel in ms.

int BrickletServoV2.getServoCurrentConfiguration(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	averagingDuration – Type: int, Unit: 1 ms, Range: [1 to 255], Default: 255

Returns the servo current configuration for the specified servo channel as set by setServoCurrentConfiguration().

void BrickletServoV2.setInputVoltageConfiguration(int averagingDuration)¶

Parameters:	averagingDuration – Type: int, Unit: 1 ms, Range: [1 to 255], Default: 255

Sets the averaging duration of the input voltage measurement for the specified servo channel in ms.

int BrickletServoV2.getInputVoltageConfiguration()¶

Returns:	averagingDuration – Type: int, Unit: 1 ms, Range: [1 to 255], Default: 255

Returns the input voltage configuration as set by setInputVoltageConfiguration().

int BrickletServoV2.getOverallCurrent()¶

Returns:	current – Type: int, Unit: 1 mA, Range: [0 to 2¹⁶ - 1]

Returns the current consumption of all servos together in mA.

int BrickletServoV2.getInputVoltage()¶

Returns:	voltage – Type: int, Unit: 1 mV, Range: [0 to 2¹⁶ - 1]

Returns the input voltage in mV. The input voltage is given via the black power input connector on the Servo Brick.

Advanced Functions¶

void BrickletServoV2.setCurrentCalibration(int[] offset)¶

Parameters:	offset – Type: int[], Length: 10, Unit: 1 mA, Range: [-2¹⁵ to 2¹⁵ - 1]

Sets an offset value (in mA) for each channel.

Note: On delivery the Servo Bricklet 2.0 is already calibrated.

int[] BrickletServoV2.getCurrentCalibration()¶

Returns:	offset – Type: int[], Length: 10, Unit: 1 mA, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the current calibration as set by setCurrentCalibration().

BrickletServoV2.SPITFPErrorCount BrickletServoV2.getSPITFPErrorCount()¶

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

void BrickletServoV2.setStatusLEDConfig(int config)¶

Parameters:	config – Type: int, Range: See constants, Default: 3

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:

For config:

BrickletServoV2.STATUS_LED_CONFIG_OFF = 0
BrickletServoV2.STATUS_LED_CONFIG_ON = 1
BrickletServoV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
BrickletServoV2.STATUS_LED_CONFIG_SHOW_STATUS = 3

int BrickletServoV2.getStatusLEDConfig()¶

Returns:	config – Type: int, Range: See constants, Default: 3

Returns the configuration as set by setStatusLEDConfig()

The following constants are available for this function:

For config:

BrickletServoV2.STATUS_LED_CONFIG_OFF = 0
BrickletServoV2.STATUS_LED_CONFIG_ON = 1
BrickletServoV2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
BrickletServoV2.STATUS_LED_CONFIG_SHOW_STATUS = 3

int BrickletServoV2.getChipTemperature()¶

Returns:	temperature – Type: int, Unit: 1 °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 bad accuracy. Practically it is only useful as an indicator for temperature changes.

void BrickletServoV2.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!

BrickletServoV2.Identity BrickletServoV2.getIdentity()¶

Return Object:

Return Object:	uid – Type: String, Length: up to 8 connectedUid – Type: String, Length: up to 8 position – Type: char, Range: ['a' to 'h', 'z'] hardwareVersion – Type: short[], Length: 3 1: major – Type: short, Range: [0 to 255] 2: minor – Type: short, Range: [0 to 255] 3: revision – Type: short, Range: [0 to 255] firmwareVersion – Type: short[], Length: 3 1: major – Type: short, Range: [0 to 255] 2: minor – Type: short, Range: [0 to 255] 3: revision – Type: short, Range: [0 to 255] deviceIdentifier – Type: int, Range: [0 to 2¹⁶ - 1]

uid – Type: String, Length: up to 8
connectedUid – Type: String, Length: up to 8
position – Type: char, Range: ['a' to 'h', 'z']
hardwareVersion – Type: short[], Length: 3

1: major – Type: short, Range: [0 to 255]
2: minor – Type: short, Range: [0 to 255]
3: revision – Type: short, Range: [0 to 255]

firmwareVersion – Type: short[], Length: 3

1: major – Type: short, Range: [0 to 255]
2: minor – Type: short, Range: [0 to 255]
3: revision – Type: short, Range: [0 to 255]

deviceIdentifier – Type: int, Range: [0 to 2¹⁶ - 1]

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', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.

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

Callback Configuration Functions¶

void BrickletServoV2.setPositionReachedCallbackConfiguration(int servoChannel, boolean enabled)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9, 2¹⁵ to 33791] enabled – Type: boolean, Default: false

Enable/Disable PositionReachedCallback callback.

boolean BrickletServoV2.getPositionReachedCallbackConfiguration(int servoChannel)¶

Parameters:	servoChannel – Type: int, Range: [0 to 9]
Returns:	enabled – Type: boolean, Default: false

Returns the callback configuration as set by setPositionReachedCallbackConfiguration().

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with "set" function of MATLAB. The parameters consist of the IP Connection object, the callback name and the callback function. For example, it looks like this in MATLAB:

function my_callback(e)
    fprintf('Parameter: %s\n', e.param);
end

set(device, 'ExampleCallback', @(h, e) my_callback(e));

Due to a difference in the Octave Java support the "set" function cannot be used in Octave. The registration is done with "add*Callback" functions of the device object. It looks like this in Octave:

function my_callback(e)
    fprintf("Parameter: %s\n", e.param);
end

device.addExampleCallback(@my_callback);

It is possible to add several callbacks and to remove them with the corresponding "remove*Callback" function.

The parameters of the callback are passed to the callback function as fields of the structure e, which is derived from the java.util.EventObject class. The available callback names with corresponding structure fields 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.

callback BrickletServoV2.PositionReachedCallback¶

Event Object:	servoChannel – Type: int, Range: [0 to 9] position – Type: int, Unit: 1/100 °, Range: ?

This callback is triggered when a position set by setPosition() is reached. If the new position matches the current position then the callback is not triggered, because the servo didn't move. The parameters are the servo and the position that is reached.

You can enable this callback with setPositionReachedCallbackConfiguration().

Note

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

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addPositionReachedCallback() function. An added callback function can be removed with the removePositionReachedCallback() function.

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.

short[] BrickletServoV2.getAPIVersion()¶

Return Object:	apiVersion – Type: short[], Length: 3 1: major – Type: short, Range: [0 to 255] 2: minor – Type: short, Range: [0 to 255] 3: revision – Type: short, 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.

boolean BrickletServoV2.getResponseExpected(byte functionId)¶

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:

BrickletServoV2.FUNCTION_SET_ENABLE = 2
BrickletServoV2.FUNCTION_SET_POSITION = 4
BrickletServoV2.FUNCTION_SET_MOTION_CONFIGURATION = 8
BrickletServoV2.FUNCTION_SET_PULSE_WIDTH = 10
BrickletServoV2.FUNCTION_SET_DEGREE = 12
BrickletServoV2.FUNCTION_SET_PERIOD = 14
BrickletServoV2.FUNCTION_SET_SERVO_CURRENT_CONFIGURATION = 17
BrickletServoV2.FUNCTION_SET_INPUT_VOLTAGE_CONFIGURATION = 19
BrickletServoV2.FUNCTION_SET_CURRENT_CALIBRATION = 23
BrickletServoV2.FUNCTION_SET_POSITION_REACHED_CALLBACK_CONFIGURATION = 25
BrickletServoV2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
BrickletServoV2.FUNCTION_SET_STATUS_LED_CONFIG = 239
BrickletServoV2.FUNCTION_RESET = 243
BrickletServoV2.FUNCTION_WRITE_UID = 248

void BrickletServoV2.setResponseExpected(byte functionId, boolean responseExpected)¶

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.

The following constants are available for this function:

For functionId:

BrickletServoV2.FUNCTION_SET_ENABLE = 2
BrickletServoV2.FUNCTION_SET_POSITION = 4
BrickletServoV2.FUNCTION_SET_MOTION_CONFIGURATION = 8
BrickletServoV2.FUNCTION_SET_PULSE_WIDTH = 10
BrickletServoV2.FUNCTION_SET_DEGREE = 12
BrickletServoV2.FUNCTION_SET_PERIOD = 14
BrickletServoV2.FUNCTION_SET_SERVO_CURRENT_CONFIGURATION = 17
BrickletServoV2.FUNCTION_SET_INPUT_VOLTAGE_CONFIGURATION = 19
BrickletServoV2.FUNCTION_SET_CURRENT_CALIBRATION = 23
BrickletServoV2.FUNCTION_SET_POSITION_REACHED_CALLBACK_CONFIGURATION = 25
BrickletServoV2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
BrickletServoV2.FUNCTION_SET_STATUS_LED_CONFIG = 239
BrickletServoV2.FUNCTION_RESET = 243
BrickletServoV2.FUNCTION_WRITE_UID = 248

void BrickletServoV2.setResponseExpectedAll(boolean responseExpected)¶

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.

int BrickletServoV2.setBootloaderMode(int mode)¶

Parameters:	mode – Type: int, Range: See constants
Returns:	status – Type: int, Range: See constants

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:

For mode:

BrickletServoV2.BOOTLOADER_MODE_BOOTLOADER = 0
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE = 1
BrickletServoV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

For status:

BrickletServoV2.BOOTLOADER_STATUS_OK = 0
BrickletServoV2.BOOTLOADER_STATUS_INVALID_MODE = 1
BrickletServoV2.BOOTLOADER_STATUS_NO_CHANGE = 2
BrickletServoV2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
BrickletServoV2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
BrickletServoV2.BOOTLOADER_STATUS_CRC_MISMATCH = 5

int BrickletServoV2.getBootloaderMode()¶

Returns:	mode – Type: int, Range: See constants

Returns the current bootloader mode, see setBootloaderMode().

The following constants are available for this function:

For mode:

BrickletServoV2.BOOTLOADER_MODE_BOOTLOADER = 0
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE = 1
BrickletServoV2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
BrickletServoV2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4

void BrickletServoV2.setWriteFirmwarePointer(long pointer)¶

Parameters:	pointer – Type: long, Unit: 1 B, Range: [0 to 2³² - 1]

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.

int BrickletServoV2.writeFirmware(int[] data)¶

Parameters:	data – Type: int[], Length: 64, Range: [0 to 255]
Returns:	status – Type: int, Range: [0 to 255]

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.

void BrickletServoV2.writeUID(long uid)¶

Parameters:	uid – Type: long, Range: [0 to 2³² - 1]

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.

long BrickletServoV2.readUID()¶

Returns:	uid – Type: long, Range: [0 to 2³² - 1]

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

Constants¶

int BrickletServoV2.DEVICE_IDENTIFIER¶

This constant is used to identify a Servo 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.

String BrickletServoV2.DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a Servo Bricklet 2.0.