// Serial.h - Definition of the CSerial class
//
// Copyright (C) 1999-2003 Ramon de Klein (Ramon.de.Klein@ict.nl)
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#ifndef __SERIAL_H
#define __SERIAL_H
//////////////////////////////////////////////////////////////////////
// The SERIAL_DEFAULT_OVERLAPPED defines if the default open mode uses
// overlapped I/O. When overlapped I/O is available (normal Win32
// platforms) it uses overlapped I/O. Windows CE doesn't allow the use
// of overlapped I/O, so it is disabled there by default.
#ifndef SERIAL_DEFAULT_OVERLAPPED
#ifndef SERIAL_NO_OVERLAPPED
#define SERIAL_DEFAULT_OVERLAPPED true
#else
#define SERIAL_DEFAULT_OVERLAPPED false
#endif
#endif
//////////////////////////////////////////////////////////////////////
//
// CSerial - Win32 wrapper for serial communications
//
// Serial communication often causes a lot of problems. This class
// tries to supply an easy to use interface to deal with serial
// devices.
//
// The class is actually pretty ease to use. You only need to open
// the COM-port, where you need to specify the basic serial
// communication parameters. You can also choose to setup handshaking
// and read timeout behaviour.
//
// The following serial classes are available:
//
// CSerial - Serial communication support.
// CSerialEx - Serial communication with listener thread for events
// CSerialSync - Serial communication with synchronized event handler
// CSerialWnd - Asynchronous serial support, which uses the Win32
// message queue for event notification.
// CSerialMFC - Preferred class to use in MFC-based GUI windows.
//
//
// Pros:
// -----
// - Easy to use (hides a lot of nasty Win32 stuff)
// - Fully ANSI and Unicode aware
//
// Cons:
// -----
// - Little less flexibility then native Win32 API, however you can
// use this API at the same time for features which are missing
// from this class.
// - Incompatible with Windows 95 or Windows NT v3.51 (or earlier),
// because CancelIo isn't support on these platforms. Define the
// SERIAL_NO_CANCELIO macro for support of these platforms as
// well. When this macro is defined, then only time-out values of
// 0 or INFINITE are valid.
//
//
// Copyright (C) 1999-2003 Ramon de Klein
// (Ramon.de.Klein@ict.nl)
class CSerial
{
// Class enumerations
public:
// Communication event
typedef enum
{
EEventUnknown = -1, // Unknown event
EEventNone = 0, // Event trigged without cause
EEventBreak = EV_BREAK, // A break was detected on input
EEventCTS = EV_CTS, // The CTS signal changed state
EEventDSR = EV_DSR, // The DSR signal changed state
EEventError = EV_ERR, // A line-status error occurred
EEventRing = EV_RING, // A ring indicator was detected
EEventRLSD = EV_RLSD, // The RLSD signal changed state
EEventRecv = EV_RXCHAR, // Data is received on input
EEventRcvEv = EV_RXFLAG, // Event character was received on input
EEventSend = EV_TXEMPTY, // Last character on output was sent
EEventPrinterError = EV_PERR, // Printer error occured
EEventRx80Full = EV_RX80FULL, // Receive buffer is 80 percent full
EEventProviderEvt1 = EV_EVENT1, // Provider specific event 1
EEventProviderEvt2 = EV_EVENT2, // Provider specific event 2
}
EEvent;
// Baudrate
typedef enum
{
EBaudUnknown = -1, // Unknown
EBaud110 = CBR_110, // 110 bits/sec
EBaud300 = CBR_300, // 300 bits/sec
EBaud600 = CBR_600, // 600 bits/sec
EBaud1200 = CBR_1200, // 1200 bits/sec
EBaud2400 = CBR_2400, // 2400 bits/sec
EBaud4800 = CBR_4800, // 4800 bits/sec
EBaud9600 = CBR_9600, // 9600 bits/sec
EBaud14400 = CBR_14400, // 14400 bits/sec
EBaud19200 = CBR_19200, // 19200 bits/sec (default)
EBaud38400 = CBR_38400, // 38400 bits/sec
EBaud56000 = CBR_56000, // 56000 bits/sec
EBaud57600 = CBR_57600, // 57600 bits/sec
EBaud115200 = CBR_115200, // 115200 bits/sec
EBaud128000 = CBR_128000, // 128000 bits/sec
EBaud256000 = CBR_256000, // 256000 bits/sec
}
EBaudrate;
// Data bits (5-8)
typedef enum
{
EDataUnknown = -1, // Unknown
EData5 = 5, // 5 bits per byte
EData6 = 6, // 6 bits per byte
EData7 = 7, // 7 bits per byte
EData8 = 8 // 8 bits per byte (default)
}
EDataBits;
// Parity scheme
typedef enum
{
EParUnknown = -1, // Unknown
EParNone = NOPARITY, // No parity (default)
EParOdd = ODDPARITY, // Odd parity
EParEven = EVENPARITY, // Even parity
EParMark = MARKPARITY, // Mark parity
EParSpace = SPACEPARITY // Space parity
}
EParity;
// Stop bits
typedef enum
{
EStopUnknown = -1, // Unknown
EStop1 = ONESTOPBIT, // 1 stopbit (default)
EStop1_5 = ONE5STOPBITS,// 1.5 stopbit
EStop2 = TWOSTOPBITS // 2 stopbits
}
EStopBits;
// Handshaking
typedef enum
{
EHandshakeUnknown = -1, // Unknown
EHandshakeOff = 0, // No handshaking
EHandshakeHardware = 1, // Hardware handshaking (RTS/CTS)
EHandshakeSoftware = 2 // Software handshaking (XON/XOFF)
}
EHandshake;
// Timeout settings
typedef enum
{
EReadTimeoutUnknown = -1, // Unknown
EReadTimeoutNonblocking = 0, // Always return immediately
EReadTimeoutBlocking = 1 // Block until everything is retrieved
}
EReadTimeout;
// Communication errors
typedef enum
{
EErrorUnknown = 0, // Unknown
EErrorBreak = CE_BREAK, // Break condition detected
EErrorFrame = CE_FRAME, // Framing error
EErrorIOE = CE_IOE, // I/O device error
EErrorMode = CE_MODE, // Unsupported mode
EErrorOverrun = CE_OVERRUN, // Character buffer overrun, next byte is lost
EErrorRxOver = CE_RXOVER, // Input buffer overflow, byte lost
EErrorParity = CE_RXPARITY,// Input parity error
EErrorTxFull = CE_TXFULL // Output buffer full
}
EError;
// Port availability
typedef enum
{
EPortUnknownError = -1, // Unknown error occurred
EPortAvailable = 0, // Port is available
EPortNotAvailable = 1, // Port is not present
EPortInUse = 2 // Port is in use
}
EPort;
// Construction
public:
CSerial();
virtual ~CSerial();
// Operations
public:
// Check if particular COM-port is available (static method).
static EPort CheckPort (LPCTSTR lpszDevice);
// Open the serial communications for a particular COM port. You
// need to use the full devicename (i.e. "COM1") to open the port.
// It's possible to specify the size of the input/output queues.
virtual LONG Open (LPCTSTR lpszDevice, DWORD dwInQueue = 0, DWORD dwOutQueue = 0, bool fOverlapped = SERIAL_DEFAULT_OVERLAPPED);
// Close the serial port.
virtual LONG Close (void);
// Setup the communication settings such as baudrate, databits,
// parity and stopbits. The default settings are applied when the
// device has been opened. Call this function if these settings do
// not apply for your application. If you prefer to use integers
// instead of the enumerated types then just cast the integer to
// the required type. So the following two initializations are
// equivalent:
//
// Setup(EBaud9600,EData8,EParNone,EStop1)
//
// or
//
// Setup(EBaudrate(9600),EDataBits(8),EParity(NOPARITY),EStopBits(ONESTOPBIT))
//
// In the latter case, the types are not validated. So make sure
// that you specify the appropriate values.
virtual LONG Setup (EBaudrate eBaudrate = EBaud9600,
EDataBits eDataBits = EData8,
EParity eParity = EParNone,
EStopBits eStopBits = EStop1);
// Set/clear the event character. When this byte is being received
// on the serial port then the EEventRcvEv event is signalled,
// when the mask has been set appropriately. If the fAdjustMask flag
// has been set, then the event mask is automatically adjusted.
virtual LONG SetEventChar (BYTE bEventChar, bool fAdjustMask = true);
// Set the event mask, which indicates what events should be
// monitored. The WaitEvent method can only monitor events that
// have been enabled. The default setting only monitors the
// error events and data events. An application may choose to
// monitor CTS. DSR, RLSD, etc as well.
virtual LONG SetMask (DWORD dwMask = EEventBreak|EEventError|EEventRecv);
// The WaitEvent method waits for one of the events that are
// enabled (see SetMask).
virtual LONG WaitEvent (LPOVERLAPPED lpOverlapped = 0, DWORD dwTimeout = INFINITE);
// Setup the handshaking protocol. There are three forms of
// handshaking:
//
// 1) No handshaking, so data is always send even if the receiver
// cannot handle the data anymore. This can lead to data loss,
// when the sender is able to transmit data faster then the
// receiver can handle.
// 2) Hardware handshaking, where the RTS/CTS lines are used to
// indicate if data can be sent. This mode requires that both
// ports and the cable support hardware handshaking. Hardware
// handshaking is the most reliable and efficient form of
// handshaking available, but is hardware dependant.
// 3) Software handshaking, where the XON/XOFF characters are used
// to throttle the data. A major drawback of this method is that
// these characters cannot be used for data anymore.
virtual LONG SetupHandshaking (EHandshake eHandshake);
// Read operations can be blocking or non-blocking. You can use
// this method to setup wether to use blocking or non-blocking
// reads. Non-blocking reads is the default, which is required
// for most applications.
//
// 1) Blocking reads, which will cause the 'Read' method to block
// until the requested number of bytes have been read. This is
// useful if you know how many data you will receive.
// 2) Non-blocking reads, which will read as many bytes into your
// buffer and returns almost immediately. This is often the
// preferred setting.
virtual LONG SetupReadTimeouts (EReadTimeout eReadTimeout);
// Obtain communication settings
virtual EBaudrate GetBaudrate (void);
virtual EDataBits GetDataBits (void);
virtual EParity GetParity (void);
virtual EStopBits GetStopBits (void);
virtual EHandshake GetHandshaking (void);
virtual DWORD GetEventMask (void);
virtual BYTE GetEventChar (void);
// Write data to the serial port. Note that we are only able to
// send ANSI strings, because it probably doesn't make sense to
// transmit Unicode strings to an application.
virtual LONG Write (const void* pData, size_t iLen, DWORD* pdwWritten = 0, LPOVERLAPPED lpOverlapped = 0, DWORD dwTimeout = INFINITE);
virtual LONG Write (LPCSTR pString, DWORD* pdwWritten = 0, LPOVERLAPPED lpOverlapped = 0, DWORD dwTimeout = INFINITE);
// Read data from the serial port. Refer to the description of
// the 'SetupReadTimeouts' for an explanation about (non) blocking
// reads and how to use this.
virtual LONG Read (void* pData, size_t iLen, DWORD* pdwRead = 0, LPOVERLAPPED lpOverlapped = 0, DWORD dwTimeout = INFINITE);
// Send a break
LONG Break (void);
// Determine what caused the event to trigger
EEvent GetEventType (void);
// Obtain the error
EError GetError (void);
// Obtain the COMM and event handle
HANDLE GetCommHandle (void) { return m_hFile; }
// Check if com-port is opened
bool IsOpen (void) const { return (m_hFile != 0); }
// Obtain last error status
LONG GetLastError (void) const { return m_lLastError; }
// Obtain CTS/DSR/RING/RLSD settings
bool GetCTS (void);
bool GetDSR (void);
bool GetRing (void);
bool GetRLSD (void);
// Purge all buffers
LONG Purge (void);
protected:
// Internal helper class which wraps DCB structure
class CDCB : public DCB
{
public:
CDCB() { DCBlength = sizeof(DCB); }
};
// Attributes
protected:
LONG m_lLastError; // Last serial error
HANDLE m_hFile; // File handle
EEvent m_eEvent; // Event type
DWORD m_dwEventMask; // Event mask
#ifndef SERIAL_NO_OVERLAPPED
HANDLE m_hevtOverlapped; // Event handle for internal overlapped operations
#endif
protected:
// Check the requirements
void CheckRequirements (LPOVERLAPPED lpOverlapped, DWORD dwTimeout) const;
// CancelIo wrapper (for Win95 compatibility)
BOOL CancelCommIo (void);
};
#endif // __SERIAL_H