private bool sendYmodemClosingPacket(byte STX, int packetNumber, int invertedPacketNumber, byte[] data, int dataSize, byte[] CRC, int crcSize)
{
/* calculate CRC */
Crc16Ccitt crc16Ccitt = new Crc16Ccitt(InitialCrcValue.Zeros);
CRC = crc16Ccitt.ComputeChecksumBytes(data);
/* send the packet */
if (!sendYmodemPacket(STX, packetNumber, invertedPacketNumber, data, dataSize, CRC, crcSize))
{
return(false);
}
return(true);
}
private bool sendYmodemInitialPacket(byte STX, int packetNumber, int invertedPacketNumber, byte[] data, int dataSize, string path, FileStream fileStream, byte[] CRC, int crcSize)
{
string fileName = System.IO.Path.GetFileName(path);
string fileSize = fileStream.Length.ToString();
/* add filename to data */
int i;
for (i = 0; i < fileName.Length && (fileName.ToCharArray()[i] != 0); i++)
{
data[i] = (byte)fileName.ToCharArray()[i];
}
data[i] = 0;
/* add filesize to data */
int j;
for (j = 0; j < fileSize.Length && (fileSize.ToCharArray()[j] != 0); j++)
{
data[(i + 1) + j] = (byte)fileSize.ToCharArray()[j];
}
data[(i + 1) + j] = 0;
/* fill the remaining data bytes with 0 */
for (int k = ((i + 1) + j) + 1; k < dataSize; k++)
{
data[k] = 0;
}
/* calculate CRC */
Crc16Ccitt crc16Ccitt = new Crc16Ccitt(InitialCrcValue.Zeros);
CRC = crc16Ccitt.ComputeChecksumBytes(data);
/* send the packet */
if (!sendYmodemPacket(STX, packetNumber, invertedPacketNumber, data, dataSize, CRC, crcSize))
{
return(false);
}
return(true);
}
private bool YmodemUpdateFile(string filePath)
{
const byte SOH = 1; // Start Of Head
const byte EOT = 4; // End Of Transmission
const byte ACK = 6; // Positive ACknowledgement
const int crcSize = 2;
//byte HEAD = 0;
// int dataSize = 1024;
int dataSize = Convert.ToInt32(cbx_PageSize.Text);
STX = getPageHead(cbx_PageSize.Text);
/* header: 3 bytes */
int proprassVal = 0;
int packetNumber = 0;
int invertedPacketNumber = 255;
/* data: 1024 bytes */
byte[] data = new byte[dataSize];
/* footer: 2 bytes */
byte[] CRC = new byte[crcSize];
/* get the file */
FileStream fileStream = new FileStream(@filePath, FileMode.Open, FileAccess.Read);
int packetCnt = (fileStream.Length % dataSize) == 0 ? (int)(fileStream.Length / dataSize) : (int)(fileStream.Length / dataSize) + 1;
progressBar1.Maximum = packetCnt;
try
{
if (!sendYmodemInitialPacket(STX, packetNumber, invertedPacketNumber, data, dataSize, filePath, fileStream, CRC, crcSize))
{
return(false);
}
if (serialPort1.ReadByte() != ACK)
{
Console.WriteLine("Can't send the initial packet.");
return(false);
}
if (serialPort1.ReadByte() != C)
{
return(false);
}
/* send packets with a cycle until we send the last byte */
int fileReadCount;
do
{
/* if this is the last packet fill the remaining bytes with 0 */
fileReadCount = fileStream.Read(data, 0, dataSize);
if (fileReadCount == 0)
{
break;
}
if (fileReadCount != dataSize)
{
for (int i = fileReadCount; i < dataSize; i++)
{
data[i] = 0;
}
}
/* calculate packetNumber */
packetNumber++;
if (packetNumber > 255)
{
packetNumber -= 256;
}
Console.WriteLine(packetNumber);
/* calculate invertedPacketNumber */
invertedPacketNumber = 255 - packetNumber;
/* calculate CRC */
Crc16Ccitt crc16Ccitt = new Crc16Ccitt(InitialCrcValue.Zeros);
CRC = crc16Ccitt.ComputeChecksumBytes(data);
/* send the packet */
if (!sendYmodemPacket(STX, packetNumber, invertedPacketNumber, data, dataSize, CRC, crcSize))
{
return(false);
}
progressBar1.Value = ++proprassVal;
/* wait for ACK */
if (serialPort1.ReadByte() != ACK)
{
Console.WriteLine("Couldn't send a packet.");
return(false);
}
} while (dataSize == fileReadCount);
/* send EOT (tell the downloader we are finished) */
serialPort1.Write(new byte[] { EOT }, 0, 1);
/* send closing packet */
packetNumber = 0;
invertedPacketNumber = 255;
data = new byte[dataSize];
CRC = new byte[crcSize];
if (!sendYmodemClosingPacket(STX, packetNumber, invertedPacketNumber, data, dataSize, CRC, crcSize))
{
return(false);
}
/* get ACK (downloader acknowledge the EOT) */
if (serialPort1.ReadByte() != ACK)
{
Console.WriteLine("Can't complete the transfer.");
return(false);
}
}
catch (TimeoutException)
{
progressBar1.Value = 0;
MessageBox.Show("数据传输超时");
}
catch (InvalidOperationException)
{
progressBar1.Value = 0;
MessageBox.Show("端口打开失败");
}
catch (IOException)
{
progressBar1.Value = 0;
MessageBox.Show("端口被中断，请检查连接");
}
finally
{
fileStream.Close();
}
Console.WriteLine("File transfer is succesful");
return(true);
}