Async::Serial Class Reference

A class for using asyncronous serial communications. More...

#include <AsyncSerial.h>

List of all members.

Public Types

• enum Parity { PARITY_NONE, PARITY_EVEN, PARITY_ODD }

  A type that defines the possible choices for parity. More...
  

• enum Flow { FLOW_NONE, FLOW_HW, FLOW_XONOFF }

  A type that defines the possible choices for flow control. More...
  

• enum Pin {
    PIN_NONE, PIN_RTS, PIN_DTR, PIN_CTS,
    PIN_DSR, PIN_DCD, PIN_RI
  }

  A type that defines the read/write pins in the serial port. More...
  

Public Member Functions

• Serial (const std::string &serial_port)

  Constuctor.
  

• ~Serial (void)

  Destructor.
  

• bool setParams (int speed, Parity parity, int bits, int stop_bits, Flow flow)

  Setup the serial port communications parameter.
  

• bool open (void)

  Open the serial port using the previously defined parameters.
  

• bool close (void)

  Close a previously opened serial port.
  

• int write (const char *buf, size_t count)

  Write data to the serial port.
  

• bool setCanonical (bool canonical)

  Set or clear canonical mode.
  

• bool stopInput (bool stop)

  Stop/start input of data.
  

• bool setPin (Pin pin, bool set)

  Set the state of one of the output pins in the serial port.
  

• bool getPin (Pin pin, bool &is_set)

  Get the state of one of the input pins in the serial port.
  

Public Attributes

• SigC::Signal2< void, char *,
  int > charactersReceived

  A signal that is emitted when there is data to read.
  

Static Public Attributes

• static const int READ_BUFSIZE = 1024

  The maximum number of characters that can be read at once.
  

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Detailed Description

A class for using asyncronous serial communications.

Author:

Tobias Blomberg

Date:

2004-08-02

Note:

The flow control code is untested. Report success/failure to me.

This class is used to communicate over an asynchronous serial link (e.g. RS-232 port). An example of how to use it is shown below.

#include <iostream>

#include <AsyncCppApplication.h>
#include <AsyncSerial.h>

using namespace std;
using namespace Async;

class MyClass : public SigC::Object
{
  public:
    MyClass(void)
    {
      serial = new Serial("/dev/ttyS0");
      serial->charactersReceived.connect(
          slot(this, &MyClass::onCharactersReceived));

      if (!serial->open())
      {
        perror("Open serial port failed");
        exit(1);
      }
      serial->setParams(9600, Serial::PARITY_NONE, 8, 1, Serial::FLOW_NONE);
      
      serial->write("Hello, serial\n", 14);
    }
    
    ~MyClass(void)
    {
      serial->close();
      delete serial;
    }

  private:
    Serial *serial;
    
    void onCharactersReceived(char *buf, int count)
    {
      cout << "Read " << count << " characters from serial port: "
           << buf << endl;
    }
};

int main(int argc, char **argv)
{
  CppApplication app;
  MyClass my_class;
  app.exec();
}

Definition at line 129 of file AsyncSerial.h.

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Member Enumeration Documentation

enum Async::Serial::Flow

A type that defines the possible choices for flow control. Enumerator: FLOW_NONE  No flow control in use. FLOW_HW  Use hardware flow control. FLOW_XONOFF  Use software (XON/XOFF) flow control. Definition at line 145 of file AsyncSerial.h.

enum Async::Serial::Parity

A type that defines the possible choices for parity. Enumerator: PARITY_NONE  Parity not used. PARITY_EVEN  Use even parity. PARITY_ODD  Use odd parity. Definition at line 135 of file AsyncSerial.h.

enum Async::Serial::Pin

A type that defines the read/write pins in the serial port. Enumerator: PIN_NONE  No pin. PIN_RTS  Output: Request To Send. PIN_DTR  Output: Data Terminal Ready. PIN_CTS  Input: Clear To Send. PIN_DSR  Input: Data Set Ready. PIN_DCD  Input: Data Carrier Detect. PIN_RI  Input: Ring Indicate. Definition at line 155 of file AsyncSerial.h.

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Constructor & Destructor Documentation

Async::Serial::Serial (  const std::string &  serial_port  )

Constuctor. Parameters: serial_port  The serial port to use

Async::Serial::~Serial (  void   )

Destructor.

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Member Function Documentation

bool Async::Serial::close (  void   )

Close a previously opened serial port. Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Use this method to close a previously opened serial port. If the port is already closed, true is returned and nothing is done.

bool Async::Serial::getPin (  Pin  pin, bool &  is_set )

Get the state of one of the input pins in the serial port. Parameters: pin  The pin to get the state of. See Serial::Pin. is_set  The result will be returned in this variable. Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Use this function to read the state of one of the input pins in the serial port. For a list of available pins see Serial::Pin.

bool Async::Serial::open (  void   )

Open the serial port using the previously defined parameters. Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Call this method to open the serial port using the parameters specified to the constructor. If the open method is called when the port is already opened, it just returns true without doing anything.

bool Async::Serial::setCanonical (  bool  canonical  )

Set or clear canonical mode. Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Call this method to configure the serial port for canonical mode. In this mode, a couple of control characters are parsed by the kernel driver and interpreted in special ways. Most notably, only whole lines of text are sent up to the application. Don't use canonical mode when the serial stream is not readable text that is split into lines with a line feed character. This function may be called both before or after the port has been opened and the setting is remembered after a close.

bool Async::Serial::setParams (  int  speed, Parity  parity, int  bits, int  stop_bits, Flow  flow )

Setup the serial port communications parameter. Parameters: speed  The serial speed to use parity  The parity to use (see Serial::Parity) bits  The number of bits in each serial word stop_bits  The number of stop bits to use flow  The type of flow control to use (see Serial::Flow) Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. This function is used to setup the serial communication parameters for the serial port. This must be done after calling the open function.

bool Async::Serial::setPin (  Pin  pin, bool  set )

Set the state of one of the output pins in the serial port. Parameters: pin  The pin to set. See Serial::Pin. set  If true the pin is set, if false the pin is cleared Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Use this function to control one of the output pins in the serial port. For a list of available pins see Serial::Pin.

bool Async::Serial::stopInput (  bool  stop  )

Stop/start input of data. Parameters: stop  Stop input if true or start input if false Returns: Return true on success or else false on failue. On failure the global variable errno will be set to indicate the cause of the error. Use this function to start/stop input of data when the flow control has been enabled.

int Async::Serial::write (  const char *  buf, size_t  count )  [inline]

Write data to the serial port. Parameters: buf  A buffer containing the data to write count  The number of bytes to write Returns: The number of bytes written is returned on success. If an error occurs, -1 is returned and the global variable errno is set to indicate the cause of the error. Definition at line 233 of file AsyncSerial.h.

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Member Data Documentation

SigC::Signal2<void, char*, int> Async::Serial::charactersReceived

A signal that is emitted when there is data to read. Parameters: buf  A buffer containing the data that has been read count  The number of bytes that was read Note: For maximum buffer size see Serial::READ_BUFSIZE This signal is emitted whenever one or more characters has been received on the serial port. The buffer is always null-terminated but the null is not included in the count. Definition at line 304 of file AsyncSerial.h.

const int Async::Serial::READ_BUFSIZE = 1024 [static]

The maximum number of characters that can be read at once. Definition at line 169 of file AsyncSerial.h.

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The documentation for this class was generated from the following file:

• AsyncSerial.h

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