IO::Modbus::PDU Struct Reference

Protocol Data Unit. More...

#include <PDU.h>

Collaboration diagram for IO::Modbus::PDU:

Classes
union	Data

Public Member Functions
Function	function () const
void	setFunction (Function function)
void	setException (Exception exception)
bool	exceptionFlag () const
Exception	exception () const
Swap byte order of any 16-bit fields
void	swapRequestByteOrder ()
void	swapResponseByteOrder ()
Get PDU size based on content
Calculation uses byte count so doesn't access any 16-bit fields
size_t	getRequestSize () const
size_t	getResponseSize () const

Public Attributes
uint8_t	functionCode
Data	data

Detailed Description

Protocol Data Unit.

Content is independent of the communication layer. Structure does NOT represent over-the-wire format as packing issues make handling PDU::Data awkward. Therefore, the other fields are unaligned and adjusted as required when sent over the wire.

byteCount field

Some functions with a byteCount field are marked as calculated. This means it doesn't need to be set when constructing requests or responses, and will be filled in later based on the values of other fields.

In other cases, a setCount method is provided to help ensure the byteCount field is set correctly.

Member Function Documentation

exception()

Exception IO::Modbus::PDU::exception ( ) const

inline

exceptionFlag()

bool IO::Modbus::PDU::exceptionFlag ( ) const

inline

function()

Function IO::Modbus::PDU::function ( ) const

inline

getRequestSize()

size_t IO::Modbus::PDU::getRequestSize ( ) const

inline

getResponseSize()

size_t IO::Modbus::PDU::getResponseSize ( ) const

inline

setException()

void IO::Modbus::PDU::setException ( Exception  exception )

inline

setFunction()

void IO::Modbus::PDU::setFunction ( Function  function )

inline

swapRequestByteOrder()

void IO::Modbus::PDU::swapRequestByteOrder

(

)

swapResponseByteOrder()

void IO::Modbus::PDU::swapResponseByteOrder

(

)

Member Data Documentation

data

Data IO::Modbus::PDU::data

functionCode

uint8_t IO::Modbus::PDU::functionCode

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The documentation for this struct was generated from the following file:

• PDU.h