IoT::Modbus

class IModbusMaster

Library: IoT/Modbus
Package: Generated
Header: IoT/Modbus/IModbusMaster.h

Description

This class defines the interface for Modbus clients.

The interface supports two basic modes of operation:

  • Asynchronous requests: One of the sendXXXRequest() methods is used to send a request to the device. The method returns as soon as the request has been sent over the wire. The device's response is reported asynchronously via an appropriate XXXResponseReceived event.
  • Synchronous requests: After sending the request, the method waits for the response from the device and directly returns it to the caller. In case no response is received within the specified timeout, a Poco::TimeoutException is thrown. If an exception message is received from the device, a ModbusException is thrown. If an incomplete or invalid message is received, a Poco::ProtocolException is thrown.

Note that asynchronous and synchronous (blocking) mode cannot be used simultaneously. Calling one of the asynchronous request methods will enable asynchronous mode. Calling one of the synchronous request methods will disable asynchronous mode. Switching to synchronous mode while a response to an asynchronous request is pending will lead to undefined results, including possible mismatch of requests and responses.

In asynchronous operation, requests are associated with a transaction ID, to tell apart multiple concurrent transactions. Transaction IDs are not guaranteed to be unique for subsequent requests. In fact, for Modbus RTU, which does not allow multiple simultaneous requests, the transaction ID will always be zero.

Inheritance

Direct Base Classes: Poco::OSP::Service

All Base Classes: Poco::OSP::Service, Poco::RefCountedObject

Known Derived Classes: ModbusMasterRemoteObject

Member Summary

Member Functions: isA, maskWriteRegister, readCoils, readDiscreteInputs, readExceptionStatus, readFIFOQueue, readHoldingRegisters, readInputRegisters, readWriteMultipleRegisters, remoting__enableEvents, remoting__typeId, reset, sendMaskWriteRegisterRequest, sendReadCoilsRequest, sendReadDiscreteInputsRequest, sendReadExceptionStatusRequest, sendReadFIFOQueueRequest, sendReadHoldingRegistersRequest, sendReadInputRegistersRequest, sendReadWriteMultipleRegistersRequest, sendRequest, sendWriteMultipleCoilsRequest, sendWriteMultipleRegistersRequest, sendWriteSingleCoilRequest, sendWriteSingleRegisterRequest, type, writeMultipleCoils, writeMultipleRegisters, writeSingleCoil, writeSingleRegister

Inherited Functions: duplicate, isA, referenceCount, release, type

Types Aliases

Ptr

using Ptr = Poco::AutoPtr < IModbusMaster >;

Constructors

IModbusMaster

IModbusMaster();

Creates a IModbusMaster.

Destructor

~IModbusMaster virtual

virtual ~IModbusMaster();

Destroys the IModbusMaster.

Member Functions

isA virtual

bool isA(
    const std::type_info & otherType
) const;

Returns true if the class is a subclass of the class given by otherType.

maskWriteRegister virtual

virtual void maskWriteRegister(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 outputAddress,
    Poco::UInt16 andMask,
    Poco::UInt16 orMask
) = 0;

Sends a Mask Write register request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readCoils virtual

virtual std::vector < bool > readCoils(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 startingAddress,
    Poco::UInt16 nOfCoils
) = 0;

Sends a Read Coils request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readDiscreteInputs virtual

virtual std::vector < bool > readDiscreteInputs(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 startingAddress,
    Poco::UInt16 nOfInputs
) = 0;

Sends a Read Discrete Inputs request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readExceptionStatus virtual

virtual Poco::UInt8 readExceptionStatus(
    Poco::UInt8 slaveAddress
) = 0;

Sends a Read Exception Status request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readFIFOQueue virtual

virtual std::vector < Poco::UInt16 > readFIFOQueue(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 fifoPointerAddress
) = 0;

Sends a Read FIFO Queue request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readHoldingRegisters virtual

virtual std::vector < Poco::UInt16 > readHoldingRegisters(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 startingAddress,
    Poco::UInt16 nOfRegisters
) = 0;

Sends a Read Holding Registers request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readInputRegisters virtual

virtual std::vector < Poco::UInt16 > readInputRegisters(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 startingAddress,
    Poco::UInt16 nOfRegisters
) = 0;

Sends a Read Input Registers request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

readWriteMultipleRegisters virtual

virtual std::vector < Poco::UInt16 > readWriteMultipleRegisters(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 writeStartingAddress,
    std::vector < Poco::UInt16 > writeValues,
    Poco::UInt16 readStartingAddress,
    Poco::UInt8 nOfReadRegisters
) = 0;

Sends a Read/Write Multiple registers request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

remoting__enableEvents virtual

virtual std::string remoting__enableEvents(
    Poco::RemotingNG::Listener::Ptr pListener,
    bool enable = bool (true)
) = 0;

Enable or disable delivery of remote events.

The given Listener instance must implement the Poco::RemotingNG::EventListener interface, otherwise this method will fail with a RemotingException.

This method is only used with Proxy objects; calling this method on a RemoteObject will do nothing.

remoting__typeId static

static const Poco::RemotingNG::Identifiable::TypeId & remoting__typeId();

Returns the TypeId of the class.

reset virtual

virtual void reset() = 0;

Resets the connection to the bus or device.

sendMaskWriteRegisterRequest virtual

virtual Poco::UInt16 sendMaskWriteRegisterRequest(
    const IoT::Modbus::MaskWriteRegisterRequest & request
) = 0;

Sends a Mask Write Register request.

A response from the device will be reported via the maskWriteRegisterResponseReceived event.

Returns the transaction ID for the request.

sendReadCoilsRequest virtual

virtual Poco::UInt16 sendReadCoilsRequest(
    const IoT::Modbus::ReadCoilsRequest & request
) = 0;

Sends a Read Coils request.

A response from the device will be reported via the readCoilsResponseReceived event.

Returns the transaction ID for the request.

sendReadDiscreteInputsRequest virtual

virtual Poco::UInt16 sendReadDiscreteInputsRequest(
    const IoT::Modbus::ReadDiscreteInputsRequest & request
) = 0;

Sends a Read Discrete Inputs request.

A response from the device will be reported via the readDiscreteInputsResponseReceived event.

Returns the transaction ID for the request.

sendReadExceptionStatusRequest virtual

virtual Poco::UInt16 sendReadExceptionStatusRequest(
    const IoT::Modbus::ReadExceptionStatusRequest & request
) = 0;

Sends a Read Exception Status request.

A response from the device will be reported via the readExceptionStatusResponseReceived event.

Returns the transaction ID for the request.

sendReadFIFOQueueRequest virtual

virtual Poco::UInt16 sendReadFIFOQueueRequest(
    const IoT::Modbus::ReadFIFOQueueRequest & request
) = 0;

Sends a Read FIFO Queue request.

A response from the device will be reported via the readFIFOQueueResponseReceived event.

Returns the transaction ID for the request.

sendReadHoldingRegistersRequest virtual

virtual Poco::UInt16 sendReadHoldingRegistersRequest(
    const IoT::Modbus::ReadHoldingRegistersRequest & request
) = 0;

Sends a Read Holding Registers request.

A response from the device will be reported via the readHoldingRegistersResponseReceived event.

Returns the transaction ID for the request.

sendReadInputRegistersRequest virtual

virtual Poco::UInt16 sendReadInputRegistersRequest(
    const IoT::Modbus::ReadInputRegistersRequest & request
) = 0;

Sends a Read Input Registers request.

A response from the device will be reported via the readInputRegistersResponseReceived event.

Returns the transaction ID for the request.

sendReadWriteMultipleRegistersRequest virtual

virtual Poco::UInt16 sendReadWriteMultipleRegistersRequest(
    const IoT::Modbus::ReadWriteMultipleRegistersRequest & request
) = 0;

Sends a Read Write Multiple Registers request.

A response from the device will be reported via the readWriteMultipleRegistersResponseReceived event.

Returns the transaction ID for the request.

sendRequest virtual

virtual Poco::UInt16 sendRequest(
    const IoT::Modbus::GenericMessage & message
) = 0;

Sends a generic Modbus message.

The caller is responsible for correct formatting of the messages's data field.

This can be used to send Modbus requests not directly supported by the ModbusMaster interface.

A response from the device will be reported via the responseReceived event or a more specific event if the response message type is supported.

Returns the transaction ID for the request.

sendWriteMultipleCoilsRequest virtual

virtual Poco::UInt16 sendWriteMultipleCoilsRequest(
    const IoT::Modbus::WriteMultipleCoilsRequest & request
) = 0;

Sends a Write Multiple Coils request.

A response from the device will be reported via the writeMultipleCoilsResponseReceived event.

Returns the transaction ID for the request.

sendWriteMultipleRegistersRequest virtual

virtual Poco::UInt16 sendWriteMultipleRegistersRequest(
    const IoT::Modbus::WriteMultipleRegistersRequest & request
) = 0;

Sends a Write Multiple Registers request.

A response from the device will be reported via the writeMultipleRegistersResponseReceived event.

Returns the transaction ID for the request.

sendWriteSingleCoilRequest virtual

virtual Poco::UInt16 sendWriteSingleCoilRequest(
    const IoT::Modbus::WriteSingleCoilRequest & request
) = 0;

Sends a Write Single Coil request.

A response from the device will be reported via the writeSingleCoilResponseReceived event.

Returns the transaction ID for the request.

sendWriteSingleRegisterRequest virtual

virtual Poco::UInt16 sendWriteSingleRegisterRequest(
    const IoT::Modbus::WriteSingleRegisterRequest & request
) = 0;

Sends a Write Single Register request.

A response from the device will be reported via the writeSingleRegisterResponseReceived event.

Returns the transaction ID for the request.

type virtual

const std::type_info & type() const;

Returns the type information for the object's class.

writeMultipleCoils virtual

virtual void writeMultipleCoils(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 outputAddress,
    std::vector < bool > values
) = 0;

Sends a Write Multiple Coils request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

writeMultipleRegisters virtual

virtual void writeMultipleRegisters(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 outputAddress,
    std::vector < Poco::UInt16 > values
) = 0;

Sends a Write Multiple Registers request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

writeSingleCoil virtual

virtual void writeSingleCoil(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 outputAddress,
    bool value
) = 0;

Sends a Write Single Coils request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

writeSingleRegister virtual

virtual void writeSingleRegister(
    Poco::UInt8 slaveAddress,
    Poco::UInt16 outputAddress,
    Poco::UInt16 value
) = 0;

Sends a Write Single Register request to the device and waits for the response.

Throws a Poco::TimeoutException if the device does not respond within the specified timeout. Throws a ModbusException if the device responds with an exception message.

Variables

badFrameReceived

Poco::BasicEvent < void > badFrameReceived;

exceptionReceived

Poco::BasicEvent < const ModbusExceptionMessage > exceptionReceived;

maskWriteRegisterResponseReceived

Poco::BasicEvent < const MaskWriteRegisterResponse > maskWriteRegisterResponseReceived;

readCoilsResponseReceived

Poco::BasicEvent < const ReadCoilsResponse > readCoilsResponseReceived;

readDiscreteInputsResponseReceived

Poco::BasicEvent < const ReadDiscreteInputsResponse > readDiscreteInputsResponseReceived;

readExceptionStatusResponseReceived

Poco::BasicEvent < const ReadExceptionStatusResponse > readExceptionStatusResponseReceived;

readFIFOQueueResponseReceived

Poco::BasicEvent < const ReadFIFOQueueResponse > readFIFOQueueResponseReceived;

readHoldingRegistersResponseReceived

Poco::BasicEvent < const ReadHoldingRegistersResponse > readHoldingRegistersResponseReceived;

readInputRegistersResponseReceived

Poco::BasicEvent < const ReadInputRegistersResponse > readInputRegistersResponseReceived;

readWriteMultipleRegistersResponseReceived

Poco::BasicEvent < const ReadWriteMultipleRegistersResponse > readWriteMultipleRegistersResponseReceived;

responseReceived

Poco::BasicEvent < const GenericMessage > responseReceived;

timeout

Poco::BasicEvent < const Poco::UInt16 > timeout;

writeMultipleCoilsResponseReceived

Poco::BasicEvent < const WriteMultipleCoilsResponse > writeMultipleCoilsResponseReceived;

writeMultipleRegistersResponseReceived

Poco::BasicEvent < const WriteMultipleRegistersResponse > writeMultipleRegistersResponseReceived;

writeSingleCoilResponseReceived

Poco::BasicEvent < const WriteSingleCoilResponse > writeSingleCoilResponseReceived;

writeSingleRegisterResponseReceived

Poco::BasicEvent < const WriteSingleRegisterResponse > writeSingleRegisterResponseReceived;

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