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typedef struct {
    char   Id;             /* internal device ID                 */
    ushort Baudrate;       /* operating speed                    */
    char   ByteSize;       /* transmit/receive byte size         */
    char   Parity;         /* 0,1,2,3, or 4                      */
    char   StopBits;       /* number of stop bits                */
    ushort RlsTimeout;     /* timeout for RLSD to be set         */
    ushort CtsTimeout;     /* timeout for CTS to be set          */
    ushort DsrTimeout;     /* timeout for DSR to be set          */
    ushort fBinary: 1;     /* binary-mode flag                   */
    ushort fRtsDisable: 1; /* disable RTS                        */
    ushort fParity: 1;     /* enable parity checking             */
    ushort fDummy: 5;
    ushort fOutX: 1;       /* enable output XON/XOFF             */
    ushort fInX: 1;        /* enable input XON/XOFF              */
    ushort fPeChar: 1;     /* enable parity-error replacement    */
    ushort fNull: 1;       /* enable null stripping              */
    ushort fChEvt: 1;      /* enable Rx character event          */
    ushort fDtrflow: 1;    /* enable DTR flow control            */
    ushort fRtsflow: 1;    /* enable RTS flow control            */
    ushort fDummy2: 1;
    char   XonChar;        /* transmit/receive XON character     */
    char   XoffChar;       /* transmit/receive XOFF character    */
    ushort XonLim;         /* transmit XON threshold             */
    ushort XoffLim;        /* transmit XOFF threshold            */
    char   PeChar;         /* parity error replacement character */
    char   EofChar;        /* end-of-input character             */
    char   EvtChar;        /* event-generating character         */
    ushort TxDelay;        /* amount of time between characters  */
} DCB;
 
The DCB structure contains the RS-232 configuration parameters for a
communication device.
 
Member       Description
────────────────────────────────────────────────────────────────────────────
 
 
Id           Specifies the device ID byte (COM1 = 0, COM2 = 1, and so on).
             This is also the value returned by the cOpen function, when
             successful.
 
Baudrate     Specifies the operating speed; any baud rate supported by the
             hardware.
 
ByteSize     Specifies the transmitting and receiving byte size; normally in
             the range 4 through 8.
 
Parity       Specifies the parity setting. The value can be one of the
             following values.
 
             Value  Meaning
             ───────────────────────────────────────────────────────────────
             0      None
 
             1      Odd
 
             2      Even
 
             3      Mark
 
             4      Space
 
StopBits     Specifies the number of stop bits. The value can be one of the
             following values.
 
             Value  Meaning
             ───────────────────────────────────────────────────────────────
             0      1 stop bit
 
             1      1.5 stop bits
 
             2      2 stop bits
 
RlsTimeout   Specifies the amount of time, in milliseconds, to wait for
             receiving-line-signal detect (RLSD) to become high. RLSD flow
             control can be achieved by specifying infinite timeout
             (0xFFFF).
 
CtsTimeout   Specifies the amount of time, in milliseconds, to wait for
             clear-to-send signal (CTS) to become high. CTS flow control can
             be achieved by specifying infinite timeout (0xFFFF).
 
DsrTimeout   Specifies the amount of time, in milliseconds, to wait for
             data-set-ready (DSR) to become high. DSR flow control can be
             achieved by specifying infinite timeout (0xFFFF).
 
fBinary      Specifies the binary-mode flag (0 is ASCII mode, 1 is binary).
             In ASCII mode, the end-of-file character (EOFCHAR) is
             recognized and remembered as the end of received data.
 
fRtsDisable  Disables the receive-transmission signal (RTS) line for as long
             as this device is open, if set. Normally, RTS is enabled when
             the device is opened and disabled when closed.
 
fParity      Enables parity checking, if set.
 
fOutX        Indicates that XON/XOFF flow control is to be used during
             transmission, if set. The transmitter halts when it receives an
             XOFF character, and starts again when it receives an XON
             character.
 
fInX         Indicates that XON/XOFF flow control is to be used during
             reception, if set.
 
fPeChar      Indicates that characters received with parity errors are to be
             replaced with the specified parity-checking characters
             (PECHAR), if set.
 
fNull        Specifies that the received null characters are to be
             discarded, if set.
 
fChEvt       Indicates that the reception of event-checking characters
             (EVTCHAR) are to be flagged as an event, if set.
 
fDtrFlow     Indicates that the data-terminal-ready signal (DTR) is to be
             used for receive flow control, if set.
 
fRtsflow     Indicates that the receive-transmission signal (RTS) is to be
             used for receive flow control, if set.
 
XonChar      Specifies the XON character for both transmit and receive.
 
XoffChar     Specifies the XOFF character for both transmit and receive.
 
XonLim       Specifies the threshold value for receive queue. When the
             receive queue comes within 10 characters of being full, it
             transmits an XOFF character. When the queue comes within 10
             characters of being empty, an XON character will be
             transmitted.
 
XoffLim      Specifies the threshold value for send queue. When the number
             of characters in the receive queue exceeds this value, an XOFF
             character is sent (if XOFF flow control is enabled) and the
             data-terminal-ready signal (DTR) is dropped (if enabled).
 
PeChar       Specifies the character to be used as replacement when a parity
             error occurs.
 
EofChar      Specifies the character that signals the end of the input.
 
EvtChar      Specifies the character that triggers an event flag.
 
TxDelay      Specifies the minimum amount of time that must pass between
             transmission of characters.
 
See Also
 
getdcb, inicom, setcom
 
 
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