//串口数据接收状态机
private void RecvPacketStateMachine(byte RecvByte)
{
switch (CurrentRecvState)
{
case RECVPACKSTATE.IdleState: //空闲态
if (RecvByte == (byte)0x5A)
{
CurrentRecvState = RECVPACKSTATE.StartFieldState;
}
else
{
CurrentRecvState = RECVPACKSTATE.IdleState;
}
break;
case RECVPACKSTATE.StartFieldState: //接收起始符
if (RecvByte == (byte)0xA5)
{
CurrentRecvState = RECVPACKSTATE.DataPacketState;
DataCnt = 0;
}
else
{
CurrentRecvState = RECVPACKSTATE.IdleState;
}
break;
case RECVPACKSTATE.DataPacketState: //接收数据
if (DataCnt < 19)
{
RecvDataField[DataCnt] = RecvByte;
DataCnt++;
CurrentRecvState = RECVPACKSTATE.DataPacketState;
}
else
{
RecvDataField[DataCnt] = RecvByte;
//若校验通过, 则解析数据
if (AppUtil.GetChecksum(RecvDataField, 0, 19) == RecvDataField[19])
{
byte DIRECT = (byte)(RecvDataField[0] >> 4); //指令方向, 先过滤一些数据
if (DIRECT == 0x02 || DIRECT == 0x04 || DIRECT == 0x08) //2:(终端-主机), 4:(中继-主机), 8:(非本组设备之间的通信)
{
SerialRecvMsg recvMsg = new SerialRecvMsg();
Array.Copy(RecvDataField, 0, recvMsg.PacketData.DataBytes, 2, RecvDataField.Length);
recvMsg.PacketData.updateDataBytesToField(); //将接收到的字节更新到数据包的各个字段(如dir, path, cmd等)
PacketHandler(recvMsg);
}
}
CurrentRecvState = RECVPACKSTATE.IdleState;
}
break;
default:
CurrentRecvState = RECVPACKSTATE.IdleState;
break;
}
}
private void RecvPacketStateMachine(byte[] RecvBytes, int length)
{
byte RecvByte;
for (int i = 0; i < length; i++)
{
RecvByte = RecvBytes[i];
switch (CurrentRecvState)
{
case RECVPACKSTATE.IdleState:
if (RecvByte == (byte)0x5A)
{
CurrentRecvState = RECVPACKSTATE.StartFieldState;
}
else
{
CurrentRecvState = RECVPACKSTATE.IdleState;
}
break;
case RECVPACKSTATE.StartFieldState:
if (RecvByte == (byte)0xA5)
{
CurrentRecvState = RECVPACKSTATE.TypeFieldState;
}
else
{
CurrentRecvState = RECVPACKSTATE.IdleState;
}
break;
case RECVPACKSTATE.TypeFieldState:
NetPacketRecv.PacketType = RecvByte;
NetPacketRecv.DataLength = 0;
CurrentRecvState = RECVPACKSTATE.LengthFieldState;
break;
case RECVPACKSTATE.LengthFieldState:
if (NetPacketRecv.DataLength < 1)
{
NetPacketRecv.DataLength_HighByte = RecvByte;
NetPacketRecv.DataLength++;
CurrentRecvState = RECVPACKSTATE.LengthFieldState;
}
else
{
NetPacketRecv.DataLength_LowByte = RecvByte;
NetPacketRecv.DataLength = (int)(((int)NetPacketRecv.DataLength_HighByte) << 8) + (int)RecvByte;
NetPacketRecv.datafield = new byte[NetPacketRecv.DataLength];
DataCnt = 0;
CurrentRecvState = RECVPACKSTATE.DataPacketState;
}
break;
case RECVPACKSTATE.DataPacketState:
NetPacketRecv.datafield[DataCnt] = RecvByte;
DataCnt++;
if (DataCnt < NetPacketRecv.DataLength)
{
CurrentRecvState = RECVPACKSTATE.DataPacketState;
}
else
{
CurrentRecvState = RECVPACKSTATE.CheckFieldState;
}
break;
case RECVPACKSTATE.CheckFieldState:
if (AppUtil.GetChecksum(new byte[4] {
NetPacketRecv.PacketType,
NetPacketRecv.DataLength_HighByte,
NetPacketRecv.DataLength_LowByte,
AppUtil.GetChecksum(NetPacketRecv.datafield, 0, NetPacketRecv.DataLength)
}, 0, 4) == RecvByte)
{
PacketParse(NetPacketRecv); //接收到了一个完整的数据包, 然后对数据包进行解码
}
CurrentRecvState = RECVPACKSTATE.IdleState;
break;
default:
CurrentRecvState = RECVPACKSTATE.IdleState;
break;
}
}
}
