Exemple #1
0
        ///////////////////////////
        //receive byte Array via XModem using either Checksum or CRC error detection
        /// ///////////////////////
        public byte[] XModemReceive(bool useCRC, XModemHandler stop)
        {
            //since we don't know how many bytes we receive it's the
            //best solution to use a MemoryStream
            System.IO.MemoryStream buf = new System.IO.MemoryStream();

            int    packetno = 1;
            int    retry = 0;
            int    i, c;
            double kb = 0;

            if (useCRC) // send and use CRC
            {
                this.writeByte(C);
            }
            else //send and don't use CRC
            {
                this.writeByte(NAK);
            }

            while (retry < 16)
            {
                try {
                    c = port.ReadByte();
                }
                catch {
                    c = 0x00;
                }

                if (c == SOH || c == STX)
                {
                    #region SOH/STX

                    retry = 0;
                    bufsz = 128; // default buffer size
                    if (c == STX)
                    {
                        bufsz = 1024; // buffer size for Xmodem1K
                    }
                    #region fill packet with datastream

                    xbuff[0] = (byte)c;
                    for (i = 0; i < (bufsz + (useCRC ? 1 : 0) + 3); i++)
                    {
                        xbuff[i + 1] = (byte)this.port.ReadByte();
                    }

                    #endregion

                    if (stop.IsCanceled)
                    {
                        break;
                    }

                    if (xbuff[1] == (byte)(~xbuff[2]) && xbuff[1] == packetno && check(useCRC, xbuff, 3, bufsz))
                    {
                        //add buffer to memory stream
                        buf.Write(xbuff, 3, bufsz);
                        this.writeByte(ACK);

                        #region fire event & increment packet number

                        //128 or 1024 Byte per package
                        double d = bufsz;
                        d  = d / 1024;
                        kb = (kb + d);

                        if (this.PacketReceived != null)
                        {
                            PacketReceived(this, null);
                        }

                        packetno++;
                        if (packetno >= 256)
                        {
                            packetno = 0;
                        }

                        #endregion
                    }
                    else
                    {
                        this.writeByte(NAK);
                    }

                    #endregion
                }
                else if (c == EOT)
                {
                    #region EOT

                    port.DiscardInBuffer();
                    this.writeByte(ACK);
                    //convert from memory stream to byte[]
                    return(buf.ToArray());

                    #endregion
                }
                else if (c == CAN)
                {
                    #region CAN

                    if (port.ReadByte() == CAN)
                    {
                        port.DiscardInBuffer();
                        this.writeByte(ACK);
                        return(null); //canceled by remote
                    }

                    #endregion
                }
                else
                {
                    retry++;
                    port.DiscardInBuffer();
                    this.writeByte(NAK);
                }
            }//while()

            //timeout
            this.writeByte(CAN);
            this.writeByte(CAN);
            this.writeByte(CAN);
            port.DiscardInBuffer();

            return(null);
        }
        ///////////////////////////
        //receive byte Array via XModem using either Checksum or CRC error detection
        /// ///////////////////////
        public byte[] XModemReceive(bool useCRC, XModemHandler stop)
        {
            //since we don't know how many bytes we receive it's the
              //best solution to use a MemoryStream
              System.IO.MemoryStream buf = new System.IO.MemoryStream();

              int packetno = 1;
              int retry = 0;
              int i, c;
              double kb = 0;

              if (useCRC) // send and use CRC
              this.writeByte(C);
              else //send and don't use CRC
              this.writeByte(NAK);

              while (retry < 16)
              {
            try {
            c = port.ReadByte();
            }
            catch {
            c = 0x00;
            }

            if (c == SOH || c == STX)
            {
              #region SOH/STX

              retry = 0;
              bufsz = 128; // default buffer size
              if (c == STX)
              bufsz = 1024; // buffer size for Xmodem1K

              #region fill packet with datastream

              xbuff[0] = (byte)c;
              for (i = 0; i < (bufsz + (useCRC ? 1 : 0) + 3); i++)
              {
            xbuff[i + 1] = (byte)this.port.ReadByte();
              }

              #endregion

              if (stop.IsCanceled) {
              break;
              }

              if (xbuff[1] == (byte)(~xbuff[2]) && xbuff[1] == packetno && check(useCRC, xbuff, 3, bufsz))
              {
            //add buffer to memory stream
            buf.Write(xbuff, 3, bufsz);
            this.writeByte(ACK);

            #region fire event & increment packet number

            //128 or 1024 Byte per package
            double d = bufsz;
            d = d / 1024;
            kb = (kb + d);

            if (this.PacketReceived != null)
              PacketReceived(this, null);

            packetno++;
            if (packetno >= 256)
              packetno = 0;

            #endregion
              }
              else
              {
            this.writeByte(NAK);
              }

              #endregion
            }
            else if (c == EOT)
            {
              #region EOT

              port.DiscardInBuffer();
              this.writeByte(ACK);
              //convert from memory stream to byte[]
              return buf.ToArray();

              #endregion
            }
            else if (c == CAN)
            {
              #region CAN

              if (port.ReadByte() == CAN)
              {
            port.DiscardInBuffer();
            this.writeByte(ACK);
            return null; //canceled by remote
              }

              #endregion
            }
            else
            {
              retry++;
              port.DiscardInBuffer();
              this.writeByte(NAK);
            }
              }//while()

              //timeout
              this.writeByte(CAN);
              this.writeByte(CAN);
              this.writeByte(CAN);
              port.DiscardInBuffer();

              return null;
        }