private void Modbus_Request_Event(object sender, Modbus.Device.ModbusSlaveRequestEventArgs e)
{
//request from master//disassemble packet from master
byte fc = e.Message.FunctionCode;
byte[] data = e.Message.MessageFrame;
byte[] byteStartAddress = new byte[] { data[3], data[2] };
byte[] byteNum = new byte[] { data[5], data[4] };
Int16 StartAddress = BitConverter.ToInt16(byteStartAddress, 0);
Int16 NumOfPoint = BitConverter.ToInt16(byteNum, 0);
//Console.WriteLine(fc.ToString() + "," + StartAddress.ToString() + "," + NumOfPoint.ToString());
}
internal IModbusMessage ApplyRequest(IModbusMessage request)
{
IModbusMessage response;
try
{
//Debug.WriteLine(request.ToString());
var eventArgs = new ModbusSlaveRequestEventArgs(request);
ModbusSlaveRequestReceived?.Invoke(this, eventArgs);
switch (request.FunctionCode)
{
case Modbus.ReadCoils:
response = ReadDiscretes(
(ReadCoilsInputsRequest)request,
DataStore,
DataStore.CoilDiscretes);
break;
case Modbus.ReadInputs:
response = ReadDiscretes(
(ReadCoilsInputsRequest)request,
DataStore,
DataStore.InputDiscretes);
break;
case Modbus.ReadHoldingRegisters:
response = ReadRegisters(
(ReadHoldingInputRegistersRequest)request,
DataStore,
DataStore.HoldingRegisters);
break;
case Modbus.ReadInputRegisters:
response = ReadRegisters(
(ReadHoldingInputRegistersRequest)request,
DataStore,
DataStore.InputRegisters);
break;
case Modbus.Diagnostics:
response = request;
break;
case Modbus.WriteSingleCoil:
response = WriteSingleCoil(
(WriteSingleCoilRequestResponse)request,
DataStore,
DataStore.CoilDiscretes);
WriteComplete?.Invoke(this, eventArgs);
break;
case Modbus.WriteSingleRegister:
response = WriteSingleRegister(
(WriteSingleRegisterRequestResponse)request,
DataStore,
DataStore.HoldingRegisters);
WriteComplete?.Invoke(this, eventArgs);
break;
case Modbus.WriteMultipleCoils:
response = WriteMultipleCoils(
(WriteMultipleCoilsRequest)request,
DataStore,
DataStore.CoilDiscretes);
WriteComplete?.Invoke(this, eventArgs);
break;
case Modbus.WriteMultipleRegisters:
response = WriteMultipleRegisters(
(WriteMultipleRegistersRequest)request,
DataStore,
DataStore.HoldingRegisters);
WriteComplete?.Invoke(this, eventArgs);
break;
case Modbus.ReadWriteMultipleRegisters:
ReadWriteMultipleRegistersRequest readWriteRequest = (ReadWriteMultipleRegistersRequest)request;
WriteMultipleRegisters(
readWriteRequest.WriteRequest,
DataStore,
DataStore.HoldingRegisters);
WriteComplete?.Invoke(this, eventArgs);
response = ReadRegisters(
readWriteRequest.ReadRequest,
DataStore,
DataStore.HoldingRegisters);
break;
default:
string msg = $"Unsupported function code {request.FunctionCode}.";
//Debug.WriteLine(msg);
throw new InvalidModbusRequestException(Modbus.IllegalFunction);
}
}
catch (InvalidModbusRequestException ex)
{
// Catches the exception for an illegal function or a custom exception from the ModbusSlaveRequestReceived event.
response = new SlaveExceptionResponse(
request.SlaveAddress,
(byte)(Modbus.ExceptionOffset + request.FunctionCode),
ex.ExceptionCode);
}
return(response);
}
internal IModbusMessage ApplyRequest(IModbusMessage request)
{
IModbusMessage response;
try
{
Debug.WriteLine(request.ToString());
var eventArgs = new ModbusSlaveRequestEventArgs(request);
ModbusSlaveRequestReceived.Raise(this, eventArgs);
switch (request.FunctionCode)
{
case Modbus.ReadCoils:
response = ReadDiscretes((ReadCoilsInputsRequest)request, DataStore, DataStore.CoilDiscretes);
break;
case Modbus.ReadInputs:
response = ReadDiscretes((ReadCoilsInputsRequest)request, DataStore, DataStore.InputDiscretes);
break;
case Modbus.ReadHoldingRegisters:
response = ReadRegisters((ReadHoldingInputRegistersRequest)request, DataStore,
DataStore.HoldingRegisters);
break;
case Modbus.ReadInputRegisters:
response = ReadRegisters((ReadHoldingInputRegistersRequest)request, DataStore,
DataStore.InputRegisters);
break;
case Modbus.Diagnostics:
response = request;
break;
case Modbus.WriteSingleCoil:
response = WriteSingleCoil((WriteSingleCoilRequestResponse)request, DataStore,
DataStore.CoilDiscretes);
WriteComplete.Raise(this, eventArgs);
break;
case Modbus.WriteSingleRegister:
response = WriteSingleRegister((WriteSingleRegisterRequestResponse)request, DataStore,
DataStore.HoldingRegisters);
WriteComplete.Raise(this, eventArgs);
break;
case Modbus.WriteMultipleCoils:
response = WriteMultipleCoils((WriteMultipleCoilsRequest)request, DataStore,
DataStore.CoilDiscretes);
WriteComplete.Raise(this, eventArgs);
break;
case Modbus.WriteMultipleRegisters:
response = WriteMultipleRegisters((WriteMultipleRegistersRequest)request, DataStore,
DataStore.HoldingRegisters);
WriteComplete.Raise(this, eventArgs);
break;
case Modbus.ReadWriteMultipleRegisters:
ReadWriteMultipleRegistersRequest readWriteRequest = (ReadWriteMultipleRegistersRequest)request;
WriteMultipleRegisters(readWriteRequest.WriteRequest, DataStore, DataStore.HoldingRegisters);
WriteComplete.Raise(this, eventArgs);
response = ReadRegisters(readWriteRequest.ReadRequest, DataStore, DataStore.HoldingRegisters);
break;
default:
string errorMessage = String.Format(CultureInfo.InvariantCulture, "Unsupported function code {0}",
request.FunctionCode);
Debug.WriteLine(errorMessage);
throw new InvalidModbusRequestException(Modbus.IllegalFunction);
}
}
catch (InvalidModbusRequestException ex) // Catches the exception for an illegal function or a custom exception from the ModbusSlaveRequestReceived event.
{
response = new SlaveExceptionResponse(request.SlaveAddress, (byte)(Modbus.ExceptionOffset + request.FunctionCode), ex.ExceptionCode);
}
return response;
}
