C# - RS232 Bricklet 2.0

This is the description of the C# API bindings for the RS232 Bricklet 2.0. General information and technical specifications for the RS232 Bricklet 2.0 are summarized in its hardware description.

An installation guide for the C# API bindings is part of their general description.

Examples

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

Loopback

Download (ExampleLoopback.cs)

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using System;
using Tinkerforge;

// For this example connect the RX pin to the TX pin on the same Bricklet

class Example
{
    private static string HOST = "localhost";
    private static int PORT = 4223;
    private static string UID = "XYZ"; // Change XYZ to the UID of your RS232 Bricklet 2.0

    // Callback function for read callback
    static void ReadCB(BrickletRS232V2 sender, char[] message)
    {
        // Assume that the message consists of ASCII characters and convert it
        // from an array of chars to a string
        Console.WriteLine("Message: \"" + new string(message) + "\"");
    }

    static void Main()
    {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickletRS232V2 rs232 = new BrickletRS232V2(UID, ipcon); // Create device object

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

        // Register read callback to function ReadCB
        rs232.ReadCallback += ReadCB;

        // Enable read callback
        rs232.EnableReadCallback();

        // Write "test" string
        rs232.Write("test".ToCharArray());

        Console.WriteLine("Press enter to exit");
        Console.ReadLine();
        ipcon.Disconnect();
    }
}

API

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

Since C# does not support multiple return values directly, we use the out keyword to return multiple values from a method.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

All methods listed below are thread-safe.

Basic Functions

public class BrickletRS232V2(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid:

BrickletRS232V2 rs232V2 = new BrickletRS232V2("YOUR_DEVICE_UID", ipcon);

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

public int Write(char[] message)

Writes characters to the RS232 interface. The characters can be binary data, ASCII or similar is not necessary.

The return value is the number of characters that were written.

See SetConfiguration() for configuration possibilities regarding baud rate, parity and so on.

public char[] Read(int length)

Returns up to length characters from receive buffer.

Instead of polling with this function, you can also use callbacks. But note that this function will return available data only when the read callback is disabled. See EnableReadCallback() and ReadCallback callback.

public void SetConfiguration(long baudrate, byte parity, byte stopbits, byte wordlength, byte flowcontrol)

Sets the configuration for the RS232 communication. Available options:

  • Baud rate between 100 and 2000000 baud.
  • Parity of none, odd or even.
  • Stop bits can be 1 or 2.
  • Word length of 5 to 8.
  • Flow control can be off, software or hardware.

The default is: 115200 baud, parity none, 1 stop bit, word length 8.

The following constants are available for this function:

  • BrickletRS232V2.PARITY_NONE = 0
  • BrickletRS232V2.PARITY_ODD = 1
  • BrickletRS232V2.PARITY_EVEN = 2
  • BrickletRS232V2.STOPBITS_1 = 1
  • BrickletRS232V2.STOPBITS_2 = 2
  • BrickletRS232V2.WORDLENGTH_5 = 5
  • BrickletRS232V2.WORDLENGTH_6 = 6
  • BrickletRS232V2.WORDLENGTH_7 = 7
  • BrickletRS232V2.WORDLENGTH_8 = 8
  • BrickletRS232V2.FLOWCONTROL_OFF = 0
  • BrickletRS232V2.FLOWCONTROL_SOFTWARE = 1
  • BrickletRS232V2.FLOWCONTROL_HARDWARE = 2
public void GetConfiguration(out long baudrate, out byte parity, out byte stopbits, out byte wordlength, out byte flowcontrol)

Returns the configuration as set by SetConfiguration().

The following constants are available for this function:

  • BrickletRS232V2.PARITY_NONE = 0
  • BrickletRS232V2.PARITY_ODD = 1
  • BrickletRS232V2.PARITY_EVEN = 2
  • BrickletRS232V2.STOPBITS_1 = 1
  • BrickletRS232V2.STOPBITS_2 = 2
  • BrickletRS232V2.WORDLENGTH_5 = 5
  • BrickletRS232V2.WORDLENGTH_6 = 6
  • BrickletRS232V2.WORDLENGTH_7 = 7
  • BrickletRS232V2.WORDLENGTH_8 = 8
  • BrickletRS232V2.FLOWCONTROL_OFF = 0
  • BrickletRS232V2.FLOWCONTROL_SOFTWARE = 1
  • BrickletRS232V2.FLOWCONTROL_HARDWARE = 2

Advanced Functions

public void SetBufferConfig(int sendBufferSize, int receiveBufferSize)

Sets the send and receive buffer size in byte. In total the buffers have to be 10240 byte (10kb) in size, the minimum buffer size is 1024 byte (1kb) for each.

The current buffer content is lost if this function is called.

The send buffer holds data that is given by Write() and can not be written yet. The receive buffer holds data that is received through RS232 but could not yet be send to the user, either by Read() or through ReadCallback callback.

The default configuration is 5120 byte (5kb) per buffer.

public void GetBufferConfig(out int sendBufferSize, out int receiveBufferSize)

Returns the buffer configuration as set by SetBufferConfig().

public void GetBufferStatus(out int sendBufferUsed, out int receiveBufferUsed)

Returns the currently used bytes for the send and received buffer.

See SetBufferConfig() for buffer size configuration.

public void GetErrorCount(out long errorCountOverrun, out long errorCountParity)

Returns the current number of overrun and parity errors.

public byte[] GetAPIVersion()

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.

public bool GetResponseExpected(byte functionId)

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.

public void SetResponseExpected(byte functionId, bool responseExpected)

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:

  • BrickletRS232V2.FUNCTION_ENABLE_READ_CALLBACK = 3
  • BrickletRS232V2.FUNCTION_DISABLE_READ_CALLBACK = 4
  • BrickletRS232V2.FUNCTION_SET_CONFIGURATION = 6
  • BrickletRS232V2.FUNCTION_SET_BUFFER_CONFIG = 8
  • BrickletRS232V2.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletRS232V2.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletRS232V2.FUNCTION_RESET = 243
  • BrickletRS232V2.FUNCTION_WRITE_UID = 248
public void SetResponseExpectedAll(bool responseExpected)

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

public void GetSPITFPErrorCount(out long errorCountAckChecksum, out long errorCountMessageChecksum, out long errorCountFrame, out long errorCountOverflow)

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.

public byte SetBootloaderMode(byte mode)

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:

  • BrickletRS232V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletRS232V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletRS232V2.BOOTLOADER_STATUS_OK = 0
  • BrickletRS232V2.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletRS232V2.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletRS232V2.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletRS232V2.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletRS232V2.BOOTLOADER_STATUS_CRC_MISMATCH = 5
public byte GetBootloaderMode()

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

  • BrickletRS232V2.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletRS232V2.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletRS232V2.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
public void SetWriteFirmwarePointer(long pointer)

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.

public byte WriteFirmware(byte[] data)

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.

public void SetStatusLEDConfig(byte config)

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:

  • BrickletRS232V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletRS232V2.STATUS_LED_CONFIG_ON = 1
  • BrickletRS232V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletRS232V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public byte GetStatusLEDConfig()

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

  • BrickletRS232V2.STATUS_LED_CONFIG_OFF = 0
  • BrickletRS232V2.STATUS_LED_CONFIG_ON = 1
  • BrickletRS232V2.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletRS232V2.STATUS_LED_CONFIG_SHOW_STATUS = 3
public short GetChipTemperature()

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.

public void 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!

public void WriteUID(long uid)

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.

public long ReadUID()

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

public void GetIdentity(out string uid, out string connectedUid, out char position, out byte[] hardwareVersion, out byte[] firmwareVersion, out int deviceIdentifier)

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

public void EnableReadCallback()

Enables the ReadCallback callback.

By default the callback is disabled.

public void DisableReadCallback()

Disables the ReadCallback callback.

By default the callback is disabled.

public bool IsReadCallbackEnabled()

Returns true if the ReadCallback callback is enabled, false otherwise.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by appending your callback handler to the corresponding event:

void MyCallback(BrickletRS232V2 sender, int value)
{
    System.Console.WriteLine("Value: " + value);
}

rs232V2.ExampleCallback += MyCallback;

The available events 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.

public event ReadCallback(BrickletRS232V2 sender, char[] message)

This callback is called if new data is available.

To enable this callback, use EnableReadCallback().

public event ErrorCountCallback(BrickletRS232V2 sender, long errorCountOverrun, long errorCountParity)

This callback is called if a new error occurs. It returns the current overrun and parity error count.

Constants

public int DEVICE_IDENTIFIER

This constant is used to identify a RS232 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.

public string DEVICE_DISPLAY_NAME

This constant represents the human readable name of a RS232 Bricklet 2.0.