Software / API Bindings / MATLAB/Octave / API Reference and Examples / Bricklets (Discontinued) / Dual Relay Bricklet

MATLAB/Octave - Dual Relay Bricklet¶

This is the description of the MATLAB/Octave API bindings for the Dual Relay Bricklet. General information and technical specifications for the Dual Relay Bricklet 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).

Simple (MATLAB)¶

Download (matlab_example_simple.m)

function matlab_example_simple()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletDualRelay;

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

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

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

    % Turn relays alternating on/off 10 times with 1 second delay
    for i = 0:4
        pause(1);
        dr.setState(true, false);
        pause(1);
        dr.setState(false, true);
    end

    input('Press key to exit\n', 's');
    ipcon.disconnect();
end

Simple (Octave)¶

Download (octave_example_simple.m)

function octave_example_simple()
    more off;

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

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

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

    % Turn relays alternating on/off 10 times with 1 second delay
    for i = 0:4
        pause(1);
        dr.setState(true, false);
        pause(1);
        dr.setState(false, true);
    end

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

Basic Functions¶

class BrickletDualRelay(String uid, IPConnection ipcon)¶

Parameters:	uid – Type: String ipcon – Type: IPConnection
Returns:	dualRelay – Type: BrickletDualRelay

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletDualRelay;

dualRelay = BrickletDualRelay('YOUR_DEVICE_UID', ipcon);

In Octave:

dualRelay = java_new("com.tinkerforge.BrickletDualRelay", "YOUR_DEVICE_UID", ipcon);

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

void BrickletDualRelay.setState(boolean relay1, boolean relay2)¶

Parameters:	relay1 – Type: boolean, Default: false relay2 – Type: boolean, Default: false

Sets the state of the relays, true means on and false means off. For example: (true, false) turns relay 1 on and relay 2 off.

If you just want to set one of the relays and don't know the current state of the other relay, you can get the state with getState() or you can use setSelectedState().

All running monoflop timers will be aborted if this function is called.

BrickletDualRelay.State BrickletDualRelay.getState()¶

Return Object:	relay1 – Type: boolean, Default: false relay2 – Type: boolean, Default: false

Returns the state of the relays, true means on and false means off.

Advanced Functions¶

void BrickletDualRelay.setMonoflop(short relay, boolean state, long time)¶

Parameters:	relay – Type: short, Range: [1 to 2] state – Type: boolean time – Type: long, Unit: 1 ms, Range: [0 to 2³² - 1]

The first parameter can be 1 or 2 (relay 1 or relay 2). The second parameter is the desired state of the relay (true means on and false means off). The third parameter indicates the time that the relay should hold the state.

If this function is called with the parameters (1, true, 1500): Relay 1 will turn on and in 1.5s it will turn off again.

A monoflop can be used as a failsafe mechanism. For example: Lets assume you have a RS485 bus and a Dual Relay Bricklet connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds. The relay will be on all the time. If now the RS485 connection is lost, the relay will turn off in at most two seconds.

BrickletDualRelay.Monoflop BrickletDualRelay.getMonoflop(short relay)¶

Parameters:	relay – Type: short, Range: [1 to 2]
Return Object:	state – Type: boolean time – Type: long, Unit: 1 ms, Range: [0 to 2³² - 1] timeRemaining – Type: long, Unit: 1 ms, Range: [0 to 2³² - 1]

Returns (for the given relay) the current state and the time as set by setMonoflop() as well as the remaining time until the state flips.

If the timer is not running currently, the remaining time will be returned as 0.

void BrickletDualRelay.setSelectedState(short relay, boolean state)¶

Parameters:	relay – Type: short, Range: [1 to 2] state – Type: boolean

Sets the state of the selected relay (1 or 2), true means on and false means off.

A running monoflop timer for the selected relay will be aborted if this function is called.

The other relay remains untouched.

BrickletDualRelay.Identity BrickletDualRelay.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.

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 BrickletDualRelay.MonoflopDoneCallback¶

Event Object:	relay – Type: short, Range: [1 to 2] state – Type: boolean

This callback is triggered whenever a monoflop timer reaches 0. The parameter contain the relay (1 or 2) and the current state of the relay (the state after the monoflop).

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 addMonoflopDoneCallback() function. An added callback function can be removed with the removeMonoflopDoneCallback() 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[] BrickletDualRelay.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 BrickletDualRelay.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:

BrickletDualRelay.FUNCTION_SET_STATE = 1
BrickletDualRelay.FUNCTION_SET_MONOFLOP = 3
BrickletDualRelay.FUNCTION_SET_SELECTED_STATE = 6

void BrickletDualRelay.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:

BrickletDualRelay.FUNCTION_SET_STATE = 1
BrickletDualRelay.FUNCTION_SET_MONOFLOP = 3
BrickletDualRelay.FUNCTION_SET_SELECTED_STATE = 6

void BrickletDualRelay.setResponseExpectedAll(boolean responseExpected)¶

Parameters:	responseExpected – Type: boolean

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

Constants¶

int BrickletDualRelay.DEVICE_IDENTIFIER¶

This constant is used to identify a Dual Relay Bricklet.

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 BrickletDualRelay.DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a Dual Relay Bricklet.