enum io.ModbusFunc
enum ModbusFunc { ReadCoils = 1, ReadDiscreteInputs = 2, ReadHoldingRegisters = 3, ReadInputRegisters = 4, WriteCoil = 5, WriteRegister = 6, ReadExceptionStatus = 7, Diagnostics = 8, GetCommEventCounter = 11, GetCommEventLog = 12, WriteMultipleCoils = 15, WriteMultipleRegisters = 16, ReportServerId = 17, ReadFileRecord = 20, WriteFileRecord = 21, MaskWriteRegister = 22, ReadWriteMultipleRegisters = 23, ReadFifoQueue = 24, EncapsulatedInterface = 43, ExceptionFlag = 0x80, };