This is the description of the MATLAB/Octave API bindings for the IO-4 Bricklet 2.0. General information and technical specifications for the IO-4 Bricklet 2.0 are summarized in its hardware description.
An installation guide for the MATLAB/Octave API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
Download (matlab_example_input.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 | function matlab_example_input()
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletIO4V2;
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = IPConnection(); % Create IP connection
io = handle(BrickletIO4V2(UID, ipcon), 'CallbackProperties'); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Get current value
value = io.getValue();
fprintf('Channel 0: %i\n', value(1));
fprintf('Channel 1: %i\n', value(2));
fprintf('Channel 2: %i\n', value(3));
fprintf('Channel 3: %i\n', value(4));
input('Press key to exit\n', 's');
ipcon.disconnect();
end
|
Download (matlab_example_output.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | function matlab_example_output()
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletIO4V2;
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = IPConnection(); % Create IP connection
io = handle(BrickletIO4V2(UID, ipcon), 'CallbackProperties'); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Configure channel 3 as output low
io.setConfiguration(3, 'o', false);
% Set channel 3 alternating high/low 10 times with 100 ms delay
for i = 0:9
pause(0.1);
io.setSelectedValue(3, true);
pause(0.1);
io.setSelectedValue(3, false);
end
input('Press key to exit\n', 's');
ipcon.disconnect();
end
|
Download (matlab_example_interrupt.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | function matlab_example_interrupt()
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickletIO4V2;
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = IPConnection(); % Create IP connection
io = handle(BrickletIO4V2(UID, ipcon), 'CallbackProperties'); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Register input value callback to function cb_input_value
set(io, 'InputValueCallback', @(h, e) cb_input_value(e));
% Set period for input value (channel 1) callback to 0.5s (500ms)
io.setInputValueCallbackConfiguration(1, 500, false);
input('Press key to exit\n', 's');
ipcon.disconnect();
end
% Callback function for input value callback
function cb_input_value(e)
fprintf('Channel: %i\n', e.channel);
fprintf('Changed: %i\n', e.changed);
fprintf('Value: %i\n', e.value);
fprintf('\n');
end
|
Download (octave_example_input.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | function octave_example_input()
more off;
HOST = "localhost";
PORT = 4223;
UID = "XYZ"; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
io = javaObject("com.tinkerforge.BrickletIO4V2", UID, ipcon); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Get current value
value = io.getValue();
fprintf("Channel 0: %d\n", value(1));
fprintf("Channel 1: %d\n", value(2));
fprintf("Channel 2: %d\n", value(3));
fprintf("Channel 3: %d\n", value(4));
input("Press key to exit\n", "s");
ipcon.disconnect();
end
|
Download (octave_example_output.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | function octave_example_output()
more off;
HOST = "localhost";
PORT = 4223;
UID = "XYZ"; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
io = javaObject("com.tinkerforge.BrickletIO4V2", UID, ipcon); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Configure channel 3 as output low
io.setConfiguration(3, "o", false);
% Set channel 3 alternating high/low 10 times with 100 ms delay
for i = 0:9
pause(0.1);
io.setSelectedValue(3, true);
pause(0.1);
io.setSelectedValue(3, false);
end
input("Press key to exit\n", "s");
ipcon.disconnect();
end
|
Download (octave_example_interrupt.m)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 | function octave_example_interrupt()
more off;
HOST = "localhost";
PORT = 4223;
UID = "XYZ"; % Change XYZ to the UID of your IO-4 Bricklet 2.0
ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
io = javaObject("com.tinkerforge.BrickletIO4V2", UID, ipcon); % Create device object
ipcon.connect(HOST, PORT); % Connect to brickd
% Don't use device before ipcon is connected
% Register input value callback to function cb_input_value
io.addInputValueCallback(@cb_input_value);
% Set period for input value (channel 1) callback to 0.5s (500ms)
io.setInputValueCallbackConfiguration(1, 500, false);
input("Press key to exit\n", "s");
ipcon.disconnect();
end
% Callback function for input value callback
function cb_input_value(e)
fprintf("Channel: %d\n", e.channel);
fprintf("Changed: %d\n", e.changed);
fprintf("Value: %d\n", e.value);
fprintf("\n");
end
|
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.
BrickletIO4V2
(String uid, IPConnection ipcon)¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID uid
.
In MATLAB:
import com.tinkerforge.BrickletIO4V2;
io4V2 = BrickletIO4V2('YOUR_DEVICE_UID', ipcon);
In Octave:
io4V2 = java_new("com.tinkerforge.BrickletIO4V2", "YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected.
BrickletIO4V2.
setValue
(boolean[] value)¶Parameters: |
|
---|
Sets the output value of all four channels. A value of true or false outputs logic 1 or logic 0 respectively on the corresponding channel.
Use setSelectedValue()
to change only one output channel state.
For example: (True, True, False, False) will turn the channels 0-1 high and the channels 2-3 low.
All running monoflop timers and PWMs will be aborted if this function is called.
Note
This function does nothing for channels that are configured as input. Pull-up
resistors can be switched on with setConfiguration()
.
BrickletIO4V2.
getValue
()¶Returns: |
|
---|
Returns the logic levels that are currently measured on the channels. This function works if the channel is configured as input as well as if it is configured as output.
BrickletIO4V2.
setSelectedValue
(int channel, boolean value)¶Parameters: |
|
---|
Sets the output value of a specific channel without affecting the other channels.
A running monoflop timer or PWM for the specific channel will be aborted if this function is called.
Note
This function does nothing for channels that are configured as input. Pull-up
resistors can be switched on with setConfiguration()
.
BrickletIO4V2.
setConfiguration
(int channel, char direction, boolean value)¶Parameters: |
|
---|
Configures the value and direction of a specific channel. Possible directions are 'i' and 'o' for input and output.
If the direction is configured as output, the value is either high or low (set as true or false).
If the direction is configured as input, the value is either pull-up or default (set as true or false).
For example:
A running monoflop timer or PWM for the specific channel will be aborted if this function is called.
The following constants are available for this function:
For direction:
BrickletIO4V2.
getConfiguration
(int channel)¶Parameters: |
|
---|---|
Return Object: |
|
Returns the channel configuration as set by setConfiguration()
.
The following constants are available for this function:
For direction:
BrickletIO4V2.
setMonoflop
(int channel, boolean value, long time)¶Parameters: |
|
---|
The first parameter is the desired state of the channel (true means output high and false means output low). The second parameter indicates the time that the channel should hold the state.
If this function is called with the parameters (true, 1500): The channel will turn on and in 1.5s it will turn off again.
A PWM for the selected channel will be aborted if this function is called.
A monoflop can be used as a failsafe mechanism. For example: Lets assume you have a RS485 bus and a IO-4 Bricklet 2.0 is connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds. The channel will be high all the time. If now the RS485 connection is lost, the channel will turn low in at most two seconds.
BrickletIO4V2.
getMonoflop
(int channel)¶Parameters: |
|
---|---|
Return Object: |
|
Returns (for the given channel) the current value and the time as set by
setMonoflop()
as well as the remaining time until the value flips.
If the timer is not running currently, the remaining time will be returned as 0.
BrickletIO4V2.
getEdgeCount
(int channel, boolean resetCounter)¶Parameters: |
|
---|---|
Returns: |
|
Returns the current value of the edge counter for the selected channel. You can
configure the edges that are counted with setEdgeCountConfiguration()
.
If you set the reset counter to true, the count is set back to 0 directly after it is read.
Note
Calling this function is only allowed for channels configured as input.
BrickletIO4V2.
setEdgeCountConfiguration
(int channel, int edgeType, int debounce)¶Parameters: |
|
---|
Configures the edge counter for a specific channel.
The edge type parameter configures if rising edges, falling edges or both are counted if the channel is configured for input. Possible edge types are:
Configuring an edge counter resets its value to 0.
If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.
Note
Calling this function is only allowed for channels configured as input.
The following constants are available for this function:
For edgeType:
BrickletIO4V2.
getEdgeCountConfiguration
(int channel)¶Parameters: |
|
---|---|
Return Object: |
|
Returns the edge type and debounce time for the selected channel as set by
setEdgeCountConfiguration()
.
Note
Calling this function is only allowed for channels configured as input.
The following constants are available for this function:
For edgeType:
BrickletIO4V2.
setPWMConfiguration
(int channel, long frequency, int dutyCycle)¶Parameters: |
|
---|
Activates a PWM for the given channel.
You need to set the channel to output before you call this function, otherwise it will
report an invalid parameter error. To turn the PWM off again, you can set the frequency to 0 or any other
function that changes a value of the channel (e.g. setSelectedValue()
).
A running monoflop timer for the given channel will be aborted if this function is called.
BrickletIO4V2.
getPWMConfiguration
(int channel)¶Parameters: |
|
---|---|
Return Object: |
|
Returns the PWM configuration as set by setPWMConfiguration()
.
BrickletIO4V2.
getSPITFPErrorCount
()¶Return Object: |
|
---|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
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.
BrickletIO4V2.
setStatusLEDConfig
(int config)¶Parameters: |
|
---|
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:
BrickletIO4V2.
getStatusLEDConfig
()¶Returns: |
|
---|
Returns the configuration as set by setStatusLEDConfig()
The following constants are available for this function:
For config:
BrickletIO4V2.
getChipTemperature
()¶Returns: |
|
---|
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.
BrickletIO4V2.
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!
BrickletIO4V2.
getIdentity
()¶Return Object: |
|
---|
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.
BrickletIO4V2.
setInputValueCallbackConfiguration
(int channel, long period, boolean valueHasToChange)¶Parameters: |
|
---|
This callback can be configured per channel.
The period is the period with which the InputValueCallback
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.
BrickletIO4V2.
getInputValueCallbackConfiguration
(int channel)¶Parameters: |
|
---|---|
Return Object: |
|
Returns the callback configuration for the given channel as set by
setInputValueCallbackConfiguration()
.
BrickletIO4V2.
setAllInputValueCallbackConfiguration
(long period, boolean valueHasToChange)¶Parameters: |
|
---|
The period is the period with which the AllInputValueCallback
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.
BrickletIO4V2.
getAllInputValueCallbackConfiguration
()¶Return Object: |
|
---|
Returns the callback configuration as set by
setAllInputValueCallbackConfiguration()
.
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.
BrickletIO4V2.
InputValueCallback
¶Event Object: |
|
---|
This callback is triggered periodically according to the configuration set by
setInputValueCallbackConfiguration()
.
The parameters are the channel, a value-changed indicator and the actual value for the channel. The changed parameter is true if the value has changed since the last callback.
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
addInputValueCallback()
function. An added callback function can be removed with
the removeInputValueCallback()
function.
BrickletIO4V2.
AllInputValueCallback
¶Event Object: |
|
---|
This callback is triggered periodically according to the configuration set by
setAllInputValueCallbackConfiguration()
.
The parameters are the same as getValue()
. Additional the
changed parameter is true if the value has changed since
the last callback.
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
addAllInputValueCallback()
function. An added callback function can be removed with
the removeAllInputValueCallback()
function.
BrickletIO4V2.
MonoflopDoneCallback
¶Event Object: |
|
---|
This callback is triggered whenever a monoflop timer reaches 0. The parameters contain the channel and the current value of the channel (the value 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 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.
BrickletIO4V2.
getAPIVersion
()¶Return Object: |
|
---|
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.
BrickletIO4V2.
getResponseExpected
(byte functionId)¶Parameters: |
|
---|---|
Returns: |
|
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:
BrickletIO4V2.
setResponseExpected
(byte functionId, boolean responseExpected)¶Parameters: |
|
---|
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:
BrickletIO4V2.
setResponseExpectedAll
(boolean responseExpected)¶Parameters: |
|
---|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
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.
BrickletIO4V2.
setBootloaderMode
(int mode)¶Parameters: |
|
---|---|
Returns: |
|
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:
For status:
BrickletIO4V2.
getBootloaderMode
()¶Returns: |
|
---|
Returns the current bootloader mode, see setBootloaderMode()
.
The following constants are available for this function:
For mode:
BrickletIO4V2.
setWriteFirmwarePointer
(long pointer)¶Parameters: |
|
---|
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.
BrickletIO4V2.
writeFirmware
(int[] data)¶Parameters: |
|
---|---|
Returns: |
|
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.
BrickletIO4V2.
writeUID
(long uid)¶Parameters: |
|
---|
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.
BrickletIO4V2.
readUID
()¶Returns: |
|
---|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
BrickletIO4V2.
DEVICE_IDENTIFIER
¶This constant is used to identify a IO-4 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.
BrickletIO4V2.
DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a IO-4 Bricklet 2.0.