mm::node::DeviceParameter Struct Reference

A single object dictionary entry held by a Device. More...

#include <device_parameter.h>

Collaboration diagram for mm::node::DeviceParameter:

Public Member Functions
uint32_t	key () const
	Returns the packed (index, subindex) key used in the parameter map.
template<typename T >
std::expected< T, std::string >	getValue () const
	Returns value as the requested type T.
std::expected< double, std::string >	numeric () const
	Returns value coerced to a double, for any numeric parameter.
std::expected< void, std::string >	setValue (const DeviceParameterValue &v)
	Sets value, coercing v into the parameter's declared data type.
template<typename T >
std::expected< void, std::string >	setValue (const T &v)
	Strongly-typed setValue overload; wraps v and coerces as above.
bool	isReadable () const
	Whether the object is readable in any state (ETG.1000.6 ObjAccess read bits 0-2).
bool	inRange (const DeviceParameterValue &v) const
	Whether v lies within [minValue, maxValue].
DeviceParameterValue	clampToRange (const DeviceParameterValue &v) const
	Returns v clamped to [minValue, maxValue].

Public Attributes
uint16_t	index {}
	CoE object index.
uint8_t	subindex {}
	CoE object subindex.
std::string	name
	Textual description from ecx_readOE.
uint16_t	objectCode {}
	OTYPE_VAR / OTYPE_ARRAY / OTYPE_RECORD (ETG.1000.6 §5).
uint16_t	dataType {}
	ETG.1020 data type code (e.g. 0x0007 = UNSIGNED32).
uint16_t	bitLength {}
	Bit length of the value.
uint16_t	access {}
	ObjAccess bitfield (read/write per-state flags).
DeviceParameterValue	value
	Last-known value; type-appropriate zero before first read.
SyncState	syncState {SyncState::Unknown}
	Freshness of value relative to the device.
std::optional< uint32_t >	unit
	ETG.1004 unit code, when reported.
std::optional< DeviceParameterValue >	defaultValue
	Slave-reported default, when available.
std::optional< DeviceParameterValue >	minValue
	Slave-reported minimum, when available.
std::optional< DeviceParameterValue >	maxValue
	Slave-reported maximum, when available.

Detailed Description

A single object dictionary entry held by a Device.

Combines immutable schema (index, subindex, name, data type, bit length, access flags, object code) with a value that is overwritten by SDO upload or PDO exchange. value is initialised to the type-appropriate zero so callers can std::visit it directly without checking for a read.

Member Function Documentation

clampToRange()

DeviceParameterValue mm::node::DeviceParameter::clampToRange

(

const DeviceParameterValue &

v

)

const

Returns v clamped to [minValue, maxValue].

Clamps numerically and returns a value of the same alternative as v. Returns v unchanged when it is non-numeric or no numeric bounds apply.

getValue()

template<typename T >

std::expected< T, std::string > mm::node::DeviceParameter::getValue ( ) const

inline

Returns value as the requested type T.

Type-exact: T must be the active variant alternative (e.g. uint32_t for an UNSIGNED32 parameter — booleans are stored as uint8_t, see defaultValueForDataType). Use numeric() when you only need a number and do not care about the exact width.

Returns

The value, or an error string if T is not the active alternative.

inRange()

bool mm::node::DeviceParameter::inRange

(

const DeviceParameterValue &

v

)

const

Whether v lies within [minValue, maxValue].

Bounds are compared via numeric coercion. Returns true when v is non-numeric or when a bound is unset/non-numeric (i.e. no constraint to violate).

isReadable()

bool mm::node::DeviceParameter::isReadable ( ) const

inline

Whether the object is readable in any state (ETG.1000.6 ObjAccess read bits 0-2).

Write-only objects (e.g. a command/trigger sub-object) report no read bits; an SDO upload of one aborts, so a bulk value refresh should skip them rather than log a spurious failure.

key()

uint32_t mm::node::DeviceParameter::key ( ) const

inline

Returns the packed (index, subindex) key used in the parameter map.

numeric()

std::expected< double, std::string > mm::node::DeviceParameter::numeric

(

)

const

Returns value coerced to a double, for any numeric parameter.

The "don't worry about the type" accessor — handy because most parameters are numbers of varying width.

Returns

The numeric value, or an error string if value is a string / raw bytes.

setValue() [1/2]

std::expected< void, std::string > mm::node::DeviceParameter::setValue

(

const DeviceParameterValue &

v

)

Sets value, coercing v into the parameter's declared data type.

Numeric inputs are static_cast into the alternative matching dataType, so setValue(5) works regardless of whether the parameter is UNSIGNED8 or UNSIGNED32 — unlike a bare variant assignment, which would store the wrong alternative. Does not touch syncState; the caller decides that.

Returns

Void on success, or an error string when v cannot be coerced (e.g. a string into a numeric parameter, or a number into a string parameter).

setValue() [2/2]

template<typename T >

std::expected< void, std::string > mm::node::DeviceParameter::setValue ( const T &  v )

inline

Strongly-typed setValue overload; wraps v and coerces as above.

Member Data Documentation

access

uint16_t mm::node::DeviceParameter::access {}

ObjAccess bitfield (read/write per-state flags).

bitLength

uint16_t mm::node::DeviceParameter::bitLength {}

Bit length of the value.

dataType

uint16_t mm::node::DeviceParameter::dataType {}

ETG.1020 data type code (e.g. 0x0007 = UNSIGNED32).

defaultValue

std::optional<DeviceParameterValue> mm::node::DeviceParameter::defaultValue

Slave-reported default, when available.

index

uint16_t mm::node::DeviceParameter::index {}

CoE object index.

maxValue

std::optional<DeviceParameterValue> mm::node::DeviceParameter::maxValue

Slave-reported maximum, when available.

minValue

std::optional<DeviceParameterValue> mm::node::DeviceParameter::minValue

Slave-reported minimum, when available.

name

std::string mm::node::DeviceParameter::name

Textual description from ecx_readOE.

objectCode

uint16_t mm::node::DeviceParameter::objectCode {}

OTYPE_VAR / OTYPE_ARRAY / OTYPE_RECORD (ETG.1000.6 §5).

subindex

uint8_t mm::node::DeviceParameter::subindex {}

CoE object subindex.

syncState

SyncState mm::node::DeviceParameter::syncState {SyncState::Unknown}

Freshness of value relative to the device.

unit

std::optional<uint32_t> mm::node::DeviceParameter::unit

ETG.1004 unit code, when reported.

value

DeviceParameterValue mm::node::DeviceParameter::value

Last-known value; type-appropriate zero before first read.

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

• libs/node/device_parameter.h
• libs/node/device_parameter.cc