private void RequestToSend()
{
m_State = CommuState.Send_Request;
SendHandshakeCode(HandshakeCodes.ENQ);
//1. NO EOT AFTER BID (ENQ)
Start_T2_Timer();
}
public SecsIDriver(SecsIMessageParser parser)
: base(parser)
{
m_QueueSendingBlock = new Queue <byte[]>();
m_RecvBuff = new byte[1024]; //actually use only 258 bytes
m_MsgParser = new SecsIMessageParser();
m_Port = new SerialPort();
m_Port.DataReceived += new SerialDataReceivedEventHandler(m_Port_DataReceived);
m_ENQ = new byte[] { 5 };
m_EOT = new byte[] { 4 };
m_ACK = new byte[] { 6 };
m_NAK = new byte[] { 7 };
m_T1_Timer = new Timer();
m_T1_Timer.Elapsed += new ElapsedEventHandler(T1_Elapsed);
m_T2_Timer = new Timer();
m_T2_Timer.Elapsed += new ElapsedEventHandler(T2_Elapsed);
m_T1_Interval = 0.5d;
m_T2_Interval = 10d;
m_T3_Interval = 45;
m_RTY = 3;
m_State = CommuState.Idle;
m_Contention = SecsIContentionType.Slave;
m_MultiBlockList = new List <byte[]>();
m_T3Hash = new Hashtable();
}
private void OnDataArrival(byte[] buffer, int length)
{
Array.Copy(buffer, 0, m_RecvBuff, m_RecvBuffIndex, length);
m_RecvBuffIndex += length;
System.Diagnostics.Debug.Print("RecvBuffIndex := " + m_RecvBuffIndex.ToString());
if (m_RecvBuffIndex > 0)
{
//LTH[0] << length of data 1 + CHECKSUM 2
byte lth = m_RecvBuff[0];
Stop_T1_Timer();
//wait until end of block
if (lth + 3 == m_RecvBuffIndex)
{
ushort checksumCal = 0;
for (int i = 1; i < m_RecvBuffIndex - 2; i++)
{
checksumCal += m_RecvBuff[i];
}
ushort checksumRecv = BitConverter.ToUInt16(
new byte[] {
m_RecvBuff[m_RecvBuffIndex - 1],
m_RecvBuff[m_RecvBuffIndex - 2]
}, 0);
if (checksumCal == checksumRecv)
{
//change State to idle
m_State = CommuState.Idle;
//if CHECK SUM is correct
SendHandshakeCode(HandshakeCodes.ACK);
byte[] header = new byte[10];
Array.Copy(m_RecvBuff, 1, header, 0, header.Length);
System.Diagnostics.Debug.Print("HEAD {0} bytes ", header.Length);
byte[] transactionIdBytes = new byte[4];
Array.Copy(header, 6, transactionIdBytes, 0, 4);
Array.Reverse(transactionIdBytes);
//transaction Id alway same in Multi-Block message
uint tid = BitConverter.ToUInt32(transactionIdBytes, 0);
System.Diagnostics.Debug.Print("Transaction ID {0} bytes ", tid);
int bodyLength = lth - 10;
if (bodyLength > 0)
{
byte[] body = new byte[bodyLength];
Array.Copy(m_RecvBuff, 11, body, 0, bodyLength);
System.Diagnostics.Debug.Print("BODY {0} bytes ", body.Length);
m_MultiBlockList.Add(body);
}
if ((header[4] & 0x80) == 0x80) //last block
{
//build up all message
int totalBytes = 10; //header
foreach (byte[] bytes in m_MultiBlockList)
{
totalBytes += bytes.Length;
}
byte[] data = new byte[totalBytes];
int index = 0;
Array.Copy(header, 0, data, 0, header.Length);
index += header.Length;
foreach (byte[] bytes in m_MultiBlockList)
{
Array.Copy(bytes, 0, data, index, bytes.Length);
index += bytes.Length;
}
m_MultiBlockList.Clear();
ProcessSecsMessageBytes(data);
}
}
else
{
//send NAK for check sum error
SendHandshakeCode(HandshakeCodes.NAK);
}
//clear buffer
Array.Clear(m_RecvBuff, 0, m_RecvBuffIndex);
m_RecvBuffIndex = 0;
}
else
{
Start_T1_Timer();
}
} //if (m_RecvBuffIndex > 0)
}
private void m_Port_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
lock (m_Locker)
{
byte[] buff = new byte[m_Port.BytesToRead];
int length = m_Port.Read(buff, 0, buff.Length);
System.Diagnostics.Debug.Print("DataReceived {0} bytes , State {1}", length, m_State);
System.Diagnostics.Debug.Print("Hex : " + GetHexString(buff));
if (length == 0)
{
return;
}
switch (m_State)
{
case CommuState.Idle:
if (length == 1)
{
System.Diagnostics.Debug.Print("RecvControlChar := " + (HandshakeCodes)buff[0]);
if ((HandshakeCodes)buff[0] == HandshakeCodes.ENQ)
{
m_State = CommuState.Receiving;
SendHandshakeCode(HandshakeCodes.EOT);
//3. NO MESSAGE AFTER EOT
Start_T1_Timer();
}
}
break;
case CommuState.Receiving:
Stop_T2_Timer();
OnDataArrival(buff, length);
break;
case CommuState.Send_Request:
System.Diagnostics.Debug.Print("RecvControlChar := " + (HandshakeCodes)buff[0]);
if ((HandshakeCodes)buff[0] == HandshakeCodes.EOT)
{
Stop_T2_Timer();
m_State = CommuState.Sending;
StartSend();
}
break;
case CommuState.Sending:
System.Diagnostics.Debug.Print("RecvControlChar := " + (HandshakeCodes)buff[0]);
if ((HandshakeCodes)buff[0] == HandshakeCodes.ACK)
{
Stop_T2_Timer();
m_State = CommuState.Idle;
}
else if ((HandshakeCodes)buff[0] == HandshakeCodes.NAK)
{
Stop_T2_Timer();
m_State = CommuState.Idle; //message failed
}
break;
}
}
if (m_State == CommuState.Idle && m_QueueSendingBlock.Count > 0)
{
RequestToSend();
}
}
private void T1_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
m_T1_Timer.Stop();
m_State = CommuState.Idle;
SendHandshakeCode(HandshakeCodes.NAK);
}