Package com.pi4j.io.serial

Interface Serial

    • Method Detail

      • open

        void open​(String device,
          int baud,
          int dataBits,
          int parity,
          int stopBits,
          int flowControl)
   throws IOException

        This opens and initializes the serial port/device and sets the communication parameters. It sets the port into raw mode (character at a time and no translations).

        (ATTENTION: the 'device' argument can only be a maximum of 128 characters.)

        Parameters:
        device - The device address of the serial port to access. You can use constant 'DEFAULT_COM_PORT' if you wish to access the default serial port provided via the GPIO header.
        baud - The baud rate to use with the serial port. (Custom baud rate are not supported)
        dataBits - The data bits to use for serial communication. (5,6,7,8)
        parity - The parity setting to use for serial communication. (None, Event, Odd, Mark, Space)
        stopBits - The stop bits to use for serial communication. (1,2)
        flowControl - The flow control option to use for serial communication. (none, hardware, software)
        Throws:
        IOException - thrown on any error.
        See Also:
        DEFAULT_COM_PORT

      • open

        void open​(String device,
          int baud)
   throws IOException

        This opens and initializes the serial port/device and sets the communication parameters. It sets the port into raw mode (character at a time and no translations). This method will use the following default serial configuration parameters: - DATA BITS = 8 - PARITY = NONE - STOP BITS = 1 - FLOW CONTROL = NONE

        (ATTENTION: the 'device' argument can only be a maximum of 128 characters.)

        Parameters:
        device - The device address of the serial port to access. You can use constant 'DEFAULT_COM_PORT' if you wish to access the default serial port provided via the GPIO header.
        baud - The baud rate to use with the serial port.
        Throws:
        IOException - thrown on any error.
        See Also:
        DEFAULT_COM_PORT

      • open

        void open​(String device,
          Baud baud,
          DataBits dataBits,
          Parity parity,
          StopBits stopBits,
          FlowControl flowControl)
   throws IOException

        This opens and initializes the serial port/device and sets the communication parameters. It sets the port into raw mode (character at a time and no translations).

        (ATTENTION: the 'device' argument can only be a maximum of 128 characters.)

        Parameters:
        device - The device address of the serial port to access. You can use constant 'DEFAULT_COM_PORT' if you wish to access the default serial port provided via the GPIO header.
        baud - The baud rate to use with the serial port.
        dataBits - The data bits to use for serial communication. (5,6,7,8)
        parity - The parity setting to use for serial communication. (None, Event, Odd, Mark, Space)
        stopBits - The stop bits to use for serial communication. (1,2)
        flowControl - The flow control option to use for serial communication. (none, hardware, software)
        Throws:
        IOException - thrown on any error.
        See Also:
        DEFAULT_COM_PORT

      • open

        void open​(SerialConfig serialConfig)
   throws IOException

        This opens and initializes the serial port/device and sets the communication parameters. It sets the port into raw mode (character at a time and no translations).

        (ATTENTION: the 'device' argument can only be a maximum of 128 characters.)

        Parameters:
        serialConfig - A serial configuration object that contains the device, baud rate, data bits, parity, stop bits, and flow control settings.
        Throws:
        IOException - thrown on any error.
        See Also:
        DEFAULT_COM_PORT

      • isOpen

        boolean isOpen()
        This method is called to determine if the serial port is already open.
        Returns:
        a value of 'true' is returned if the serial port is already open.
        See Also:
        open(String, int)

      • isClosed

        boolean isClosed()
        This method is called to determine if the serial port is already closed.
        Returns:
        a value of 'true' is returned if the serial port is already in the closed state.
        See Also:
        open(String, int)

      • discardAll

        void discardAll()
         throws IllegalStateException,
                IOException

        Discards any data in both the serial receive and transmit buffers. Please note that this does not force the transmission of data, it discards it!

        Throws:
        IllegalStateException - thrown if the serial port is not already open.
        IOException - thrown on any error.

      • sendBreak

        void sendBreak​(int duration)
        throws IllegalStateException,
               IOException

        Send a BREAK signal to connected device.

        Parameters:
        duration - The length of time (milliseconds) to send the BREAK signal
        Throws:
        IllegalStateException - thrown if the serial port is not already open.
        IOException - thrown on any error.

      • setBreak

        void setBreak​(boolean enabled)
       throws IllegalStateException,
              IOException

        Send a constant BREAK signal to connected device. (Turn break on/off) When enabled this will send a steady stream of zero bits. When enabled, no (other) data transmitting is possible.

        Parameters:
        enabled - The enable or disable state to control the BREAK signal
        Throws:
        IllegalStateException - thrown if the serial port is not already open.
        IOException - thrown on any error.

      • setRTS

        void setRTS​(boolean enabled)
     throws IllegalStateException,
            IOException

        Control the RTS (request-to-send) pin state. When enabled this will set the RTS pin to the HIGH state.

        Parameters:
        enabled - The enable or disable state to control the RTS pin state.
        Throws:
        IllegalStateException - thrown if the serial port is not already open.
        IOException - thrown on any error.

      • setDTR

        void setDTR​(boolean enabled)
     throws IllegalStateException,
            IOException

        Control the DTR (data-terminal-ready) pin state. When enabled this will set the DTR pin to the HIGH state.

        Parameters:
        enabled - The enable or disable state to control the RTS pin state.
        Throws:
        IllegalStateException - thrown if the serial port is not already open.
        IOException - thrown on any error.

      • addListener

        void addListener​(SerialDataEventListener... listener)

        Java consumer code can call this method to register itself as a listener for serial data events.

        Parameters:
        listener - A class instance that implements the SerialListener interface.
        See Also:
        SerialDataEventListener, SerialDataEvent

      • removeListener

        void removeListener​(SerialDataEventListener... listener)

        Java consumer code can call this method to unregister itself as a listener for serial data events.

        Parameters:
        listener - A class instance that implements the SerialListener interface.
        See Also:
        SerialDataEventListener, SerialDataEvent

      • getFileDescriptor

        int getFileDescriptor()
        This method returns the serial device file descriptor
        Returns:
        fileDescriptor file descriptor

      • getInputStream

        InputStream getInputStream()
        This method returns the input data stream for the serial port's receive buffer
        Returns:
        InputStream input stream

      • getOutputStream

        OutputStream getOutputStream()
        This method returns the output data stream for the serial port's transmit buffer
        Returns:
        OutputStream output stream

      • isBufferingDataReceived

        boolean isBufferingDataReceived()
        This method returns the buffering state for data received from the serial device/port.
        Returns:
        'true' if buffering is enabled; else 'false'

      • setBufferingDataReceived

        void setBufferingDataReceived​(boolean enabled)

        This method controls the buffering state for data received from the serial device/port.

        If the buffering state is enabled, then all data bytes received from the serial port will get copied into a data receive buffer. You can use the 'getInputStream()' or and of the 'read()' methods to access this data. The data will also be available via the 'SerialDataEvent' event. It is important to know that if you are using data buffering, the data will continue to grow in memory until your program consume it from the data reader/stream.

        If the buffering state is disabled, then all data bytes received from the serial port will NOT get copied into the data receive buffer, but will be included in the 'SerialDataEvent' event's data payload. If you program does not care about or use data received from the serial port, then you should disable the data buffering state to prevent memory waste/leak.

        Parameters:
        enabled - Sets the buffering behavior state.