Visual Basic .NET - IO-4 Bricklet 2.0

This is the description of the Visual Basic .NET 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 Visual Basic .NET API bindings is part of their general description.

Examples

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

Output

Download (ExampleOutput.vb)

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Imports System
Imports System.Threading
Imports Tinkerforge

Module ExampleOutput
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XYZ" ' Change XYZ to the UID of your IO-4 Bricklet 2.0

    Sub Main()
        Dim ipcon As New IPConnection() ' Create IP connection
        Dim io As New 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"C, False)

        ' Set channel 3 alternating high/low 10 times with 100 ms delay
        Dim i As Integer
        For i = 0 To 9
            Thread.Sleep(100)
            io.SetSelectedValue(3, True)
            Thread.Sleep(100)
            io.SetSelectedValue(3, False)
        Next i

        Console.WriteLine("Press key to exit")
        Console.ReadLine()
        ipcon.Disconnect()
    End Sub
End Module

Interrupt

Download (ExampleInterrupt.vb)

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Imports System
Imports Tinkerforge

Module ExampleInterrupt
    Const HOST As String = "localhost"
    Const PORT As Integer = 4223
    Const UID As String = "XYZ" ' Change XYZ to the UID of your IO-4 Bricklet 2.0

    ' Callback subroutine for input value callback
    Sub InputValueCB(ByVal sender As BrickletIO4V2, ByVal channel As Byte, _
                     ByVal changed As Boolean, ByVal value As Boolean)
        Console.WriteLine("Channel: " + channel.ToString())
        Console.WriteLine("Changed: " + changed.ToString())
        Console.WriteLine("Value: " + value.ToString())
        Console.WriteLine("")
    End Sub

    Sub Main()
        Dim ipcon As New IPConnection() ' Create IP connection
        Dim io As New 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 subroutine InputValueCB
        AddHandler io.InputValueCallback, AddressOf InputValueCB

        ' Set period for input value (channel 1) callback to 0.5s (500ms)
        io.SetInputValueCallbackConfiguration(1, 500, False)

        Console.WriteLine("Press key to exit")
        Console.ReadLine()
        ipcon.Disconnect()
    End Sub
End Module

API

Since Visual Basic .NET does not support multiple return values directly, we use the ByRef keyword to return multiple values from a function.

All functions and procedures listed below are thread-safe.

Basic Functions

Class BrickletIO4V2(ByVal uid As String, ByVal ipcon As IPConnection)

Creates an object with the unique device ID uid:

Dim io4V2 As New BrickletIO4V2("YOUR_DEVICE_UID", ipcon)

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

Sub BrickletIO4V2.SetValue(ByVal value() As Boolean)

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.

Note

This function does nothing for channels that are configured as input. Pull-up resistors can be switched on with SetConfiguration().

Function BrickletIO4V2.GetValue() As Boolean()

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.

Sub BrickletIO4V2.SetSelectedValue(ByVal channel As Byte, ByVal value As Boolean)

Sets the output value of a specific channel without affecting the other channels.

Note

This function does nothing for channels that are configured as input. Pull-up resistors can be switched on with SetConfiguration().

Sub BrickletIO4V2.SetConfiguration(ByVal channel As Byte, ByVal direction As Char, ByVal value As Boolean)

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:

  • (0, 'i', true) will set channel 0 as input pull-up.
  • (1, 'i', false) will set channel 1 as input default (floating if nothing is connected).
  • (2, 'o', true) will set channel 2 as output high.
  • (3, 'o', false) will set channel 3 as output low.

The default configuration is input with pull-up.

The following constants are available for this function:

  • BrickletIO4V2.DIRECTION_IN = "i"C
  • BrickletIO4V2.DIRECTION_OUT = "o"C

Advanced Functions

Sub BrickletIO4V2.SetMonoflop(ByVal channel As Byte, ByVal value As Boolean, ByVal time As Long)

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 (in ms) 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 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.

Sub BrickletIO4V2.GetMonoflop(ByVal channel As Byte, ByRef value As Boolean, ByRef time As Long, ByRef timeRemaining As Long)

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.

Function BrickletIO4V2.GetEdgeCount(ByVal channel As Byte, ByVal resetCounter As Boolean) As Long

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.

Sub BrickletIO4V2.SetEdgeCountConfiguration(ByVal channel As Byte, ByVal edgeType As Byte, ByVal debounce As Byte)

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:

  • 0 = rising (default)
  • 1 = falling
  • 2 = both

The debounce time is given in ms.

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.

Default values: 0 (edge type) and 100ms (debounce time)

The following constants are available for this function:

  • BrickletIO4V2.EDGE_TYPE_RISING = 0
  • BrickletIO4V2.EDGE_TYPE_FALLING = 1
  • BrickletIO4V2.EDGE_TYPE_BOTH = 2
Sub BrickletIO4V2.GetEdgeCountConfiguration(ByVal channel As Byte, ByRef edgeType As Byte, ByRef debounce As Byte)

Returns the edge type and debounce time for the selected channel as set by SetEdgeCountConfiguration().

The following constants are available for this function:

  • BrickletIO4V2.EDGE_TYPE_RISING = 0
  • BrickletIO4V2.EDGE_TYPE_FALLING = 1
  • BrickletIO4V2.EDGE_TYPE_BOTH = 2
Sub BrickletIO4V2.SetPWMConfiguration(ByVal channel As Byte, ByVal frequency As Long, ByVal dutyCycle As Integer)

Activates a PWM for the given channel with the frequency given in 1/10Hz and the duty cycle given in 1/100%.

You need to set the channel to output before you call this function, otherwise it will be ignored. 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()).

The maximum frequency value is 320000000 (32MHz). The maximum duty cycle value is 10000 (100%).

The default values are 0, 0.

Sub BrickletIO4V2.GetPWMConfiguration(ByVal channel As Byte, ByRef frequency As Long, ByRef dutyCycle As Integer)

Returns the PWM configuration as set by SetPWMConfiguration().

Function BrickletIO4V2.GetAPIVersion() As Byte()

Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

Function BrickletIO4V2.GetResponseExpected(ByVal functionId As Byte) As 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 send and errors are silently ignored, because they cannot be detected.

See SetResponseExpected() for the list of function ID constants available for this function.

Sub BrickletIO4V2.SetResponseExpected(ByVal functionId As Byte, ByVal responseExpected As 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 send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletIO4V2.FUNCTION_SET_VALUE = 1
  • BrickletIO4V2.FUNCTION_SET_SELECTED_VALUE = 3
  • BrickletIO4V2.FUNCTION_SET_CONFIGURATION = 4
  • BrickletIO4V2.FUNCTION_SET_INPUT_VALUE_CALLBACK_CONFIGURATION = 6
  • BrickletIO4V2.FUNCTION_SET_ALL_INPUT_VALUE_CALLBACK_CONFIGURATION = 8
  • BrickletIO4V2.FUNCTION_SET_MONOFLOP = 10
  • BrickletIO4V2.FUNCTION_SET_EDGE_COUNT_CONFIGURATION = 13
  • BrickletIO4V2.FUNCTION_SET_PWM_CONFIGURATION = 15
  • BrickletIO4V2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletIO4V2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletIO4V2.FUNCTION_RESET = 243
  • BrickletIO4V2.FUNCTION_WRITE_UID = 248
Sub BrickletIO4V2.SetResponseExpectedAll(ByVal responseExpected As Boolean)

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

Sub BrickletIO4V2.GetSPITFPErrorCount(ByRef errorCountAckChecksum As Long, ByRef errorCountMessageChecksum As Long, ByRef errorCountFrame As Long, ByRef errorCountOverflow As Long)

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.

Function BrickletIO4V2.SetBootloaderMode(ByVal mode As Byte) As Byte

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:

  • BrickletIO4V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletIO4V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletIO4V2.BOOTLOADER_STATUS_OK = 0
  • BrickletIO4V2.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletIO4V2.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletIO4V2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletIO4V2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletIO4V2.BOOTLOADER_STATUS_CRC_MISMATCH = 5
Function BrickletIO4V2.GetBootloaderMode() As Byte

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

  • BrickletIO4V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletIO4V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletIO4V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
Sub BrickletIO4V2.SetWriteFirmwarePointer(ByVal pointer As Long)

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.

Function BrickletIO4V2.WriteFirmware(ByVal data() As Byte) As Byte

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.

Sub BrickletIO4V2.SetStatusLEDConfig(ByVal config As Byte)

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:

  • BrickletIO4V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletIO4V2.STATUS_LED_CONFIG_ON = 1
  • BrickletIO4V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletIO4V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
Function BrickletIO4V2.GetStatusLEDConfig() As Byte

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

  • BrickletIO4V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletIO4V2.STATUS_LED_CONFIG_ON = 1
  • BrickletIO4V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletIO4V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
Function BrickletIO4V2.GetChipTemperature() As Short

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

Sub 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!

Sub BrickletIO4V2.WriteUID(ByVal uid As Long)

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.

Function BrickletIO4V2.ReadUID() As Long

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

Sub BrickletIO4V2.GetIdentity(ByRef uid As String, ByRef connectedUid As String, ByRef position As Char, ByRef hardwareVersion() As Byte, ByRef firmwareVersion() As Byte, ByRef deviceIdentifier As Integer)

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c' or 'd'.

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

Callback Configuration Functions

Sub BrickletIO4V2.GetConfiguration(ByVal channel As Byte, ByRef direction As Char, ByRef value As Boolean)

Returns the channel configuration as set by SetConfiguration().

The following constants are available for this function:

  • BrickletIO4V2.DIRECTION_IN = "i"C
  • BrickletIO4V2.DIRECTION_OUT = "o"C
Sub BrickletIO4V2.SetInputValueCallbackConfiguration(ByVal channel As Byte, ByVal period As Long, ByVal valueHasToChange As Boolean)

This callback can be configured per channel.

The period in ms 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.

The default value is (0, false).

Sub BrickletIO4V2.GetInputValueCallbackConfiguration(ByVal channel As Byte, ByRef period As Long, ByRef valueHasToChange As Boolean)

Returns the callback configuration for the given channel as set by SetInputValueCallbackConfiguration().

Sub BrickletIO4V2.SetAllInputValueCallbackConfiguration(ByVal period As Long, ByVal valueHasToChange As Boolean)

The period in ms 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.

The default value is (0, false).

Sub BrickletIO4V2.GetAllInputValueCallbackConfiguration(ByRef period As Long, ByRef valueHasToChange As Boolean)

Returns the callback configuration as set by SetAllInputValueCallbackConfiguration().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a procedure to an callback property of the device object:

Sub MyCallback(ByVal sender As BrickletIO4V2, ByVal value As Short)
    Console.WriteLine("Value: {0}", value)
End Sub

AddHandler io4V2.ExampleCallback, AddressOf MyCallback

The available callback property and their type of parameters 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.

Event BrickletIO4V2.InputValueCallback(ByVal sender As BrickletIO4V2, ByVal channel As Byte, ByVal changed As Boolean, ByVal value As Boolean)

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.

Event BrickletIO4V2.AllInputValueCallback(ByVal sender As BrickletIO4V2, ByVal changed() As Boolean, ByVal value() As Boolean)

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.

Event BrickletIO4V2.MonoflopDoneCallback(ByVal sender As BrickletIO4V2, ByVal channel As Byte, ByVal value As Boolean)

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).

Constants

Const BrickletIO4V2.DEVICE_IDENTIFIER

This constant is used to identify a IO-4 Bricklet 2.0.

The GetIdentity() function and the EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

Const BrickletIO4V2.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a IO-4 Bricklet 2.0.