idfxx::onewire::bus Class Reference

1-Wire bus controller with thread-safe access. More...

Public Member Functions
	bus (gpio pin)
	Creates a new 1-Wire bus controller.
	~bus ()=default
	bus (const bus &)=delete
bus &	operator= (const bus &)=delete
	bus (bus &&other) noexcept=default
bus &	operator= (bus &&other) noexcept=default
void	lock () const
	Acquires exclusive access to the bus.
bool	try_lock () const noexcept
	Tries to acquire exclusive access without blocking.
void	unlock () const
	Releases exclusive access to the bus.
gpio	pin () const noexcept
	Returns the GPIO pin.
bool	reset ()
	Performs a 1-Wire reset cycle.
void	select (address addr)
	Selects a specific device by ROM address.
void	skip_rom ()
	Selects all devices on the bus.
result< void >	try_select (address addr)
	Selects a specific device by ROM address.
result< void >	try_skip_rom ()
	Selects all devices on the bus.
void	write (uint8_t value)
	Writes a single byte to the bus.
void	write (std::span< const uint8_t > data)
	Writes multiple bytes to the bus.
result< void >	try_write (uint8_t value)
	Writes a single byte to the bus.
result< void >	try_write (std::span< const uint8_t > data)
	Writes multiple bytes to the bus.
uint8_t	read ()
	Reads a single byte from the bus.
void	read (std::span< uint8_t > buf)
	Reads multiple bytes from the bus into a buffer.
result< uint8_t >	try_read ()
	Reads a single byte from the bus.
result< void >	try_read (std::span< uint8_t > buf)
	Reads multiple bytes from the bus into a buffer.
void	power ()
	Actively drives the bus high for parasitic power.
result< void >	try_power ()
	Actively drives the bus high for parasitic power.
void	depower () noexcept
	Stops driving power onto the bus.
std::vector< address >	search (size_t max_devices=8)
	Searches for all devices on the bus.
std::vector< address >	search (uint8_t family_code, size_t max_devices=8)
	Searches for devices with a specific family code.
result< std::vector< address > >	try_search (size_t max_devices=8)
	Searches for all devices on the bus.
result< std::vector< address > >	try_search (uint8_t family_code, size_t max_devices=8)
	Searches for devices with a specific family code.

Static Public Member Functions
static result< bus >	make (gpio pin)
	Creates a new 1-Wire bus controller.

Detailed Description

1-Wire bus controller with thread-safe access.

Provides low-level 1-Wire bus operations: reset, ROM commands, data transfer, parasitic power control, and device search. Satisfies the Lockable named requirement for use with std::lock_guard and std::unique_lock.

This type is non-copyable and move-only. Result-returning methods on a moved-from object return errc::invalid_state. Simple accessors return default/null values. The Lockable methods (lock/try_lock/unlock) silently no-op on a moved-from object.

auto bus = idfxx::onewire::bus(idfxx::gpio_4);
if (bus.reset()) {
    bus.skip_rom();
    bus.write(0x44);  // Convert T command
}

Definition at line 170 of file onewire.hpp.

Constructor & Destructor Documentation

bus() [1/3]

idfxx::onewire::bus::bus ( gpio  pin )

explicit

Creates a new 1-Wire bus controller.

Parameters

pin	GPIO pin connected to the 1-Wire bus.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

if the pin is not connected.

~bus()

idfxx::onewire::bus::~bus ( )

default

bus() [2/3]

idfxx::onewire::bus::bus ( const bus &  )

delete

bus() [3/3]

idfxx::onewire::bus::bus ( bus &&  other )

defaultnoexcept

Member Function Documentation

depower()

void idfxx::onewire::bus::depower ( )

noexcept

Stops driving power onto the bus.

Only needed after a previous call to power(). Note that reset() will also automatically depower the bus.

lock()

void idfxx::onewire::bus::lock ( ) const

inline

Acquires exclusive access to the bus.

Definition at line 200 of file onewire.hpp.

make()

static result< bus > idfxx::onewire::bus::make ( gpio  pin )

static

Creates a new 1-Wire bus controller.

Parameters

pin	GPIO pin connected to the 1-Wire bus.

Returns

The new bus, or an error if the pin is not connected.

Return values

invalid_state

If the pin is not connected.

operator=() [1/2]

bus & idfxx::onewire::bus::operator= ( bus &&  other )

defaultnoexcept

operator=() [2/2]

bus & idfxx::onewire::bus::operator= ( const bus &  )

delete

pin()

gpio idfxx::onewire::bus::pin ( ) const

inlinenoexcept

Returns the GPIO pin.

Definition at line 224 of file onewire.hpp.

power()

void idfxx::onewire::bus::power ( )

inline

Actively drives the bus high for parasitic power.

Some devices need more power than the pull-up resistor can provide during certain operations (e.g., temperature conversion).

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on failure (e.g., bus is being held low).

Definition at line 373 of file onewire.hpp.

References try_power(), and idfxx::unwrap().

read() [1/2]

uint8_t idfxx::onewire::bus::read ( )

inline

Reads a single byte from the bus.

Returns

The byte read.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 334 of file onewire.hpp.

References try_read(), and idfxx::unwrap().

read() [2/2]

void idfxx::onewire::bus::read ( std::span< uint8_t >  buf )

inline

Reads multiple bytes from the bus into a buffer.

Parameters

buf	The buffer to read into.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 343 of file onewire.hpp.

References try_read(), and idfxx::unwrap().

reset()

bool idfxx::onewire::bus::reset

(

)

Performs a 1-Wire reset cycle.

Must be called before issuing ROM commands (select/skip_rom).

Returns

true if at least one device responds with a presence pulse, false if no devices were detected (or the bus is shorted).

search() [1/2]

std::vector< address > idfxx::onewire::bus::search ( size_t  max_devices = 8 )

inline

Searches for all devices on the bus.

Parameters

max_devices

Maximum number of devices to discover.

Returns

A vector of discovered device addresses.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 405 of file onewire.hpp.

References try_search(), and idfxx::unwrap().

search() [2/2]

std::vector< address > idfxx::onewire::bus::search ( uint8_t  family_code, size_t  max_devices = 8  )

inline

Searches for devices with a specific family code.

Parameters

family_code	The family code to filter by (e.g., 0x28 for DS18B20).
max_devices	Maximum number of devices to discover.

Returns

A vector of discovered device addresses matching the family code.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 416 of file onewire.hpp.

References try_search(), and idfxx::unwrap().

select()

void idfxx::onewire::bus::select ( address  addr )

inline

Selects a specific device by ROM address.

Issues a "ROM select" command on the bus. A reset() must be performed before calling this method.

Parameters

addr	The ROM address of the device to select.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 251 of file onewire.hpp.

References try_select(), and idfxx::unwrap().

skip_rom()

void idfxx::onewire::bus::skip_rom ( )

inline

Selects all devices on the bus.

Issues a "skip ROM" command. A reset() must be performed before calling this method.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 262 of file onewire.hpp.

References try_skip_rom(), and idfxx::unwrap().

try_lock()

bool idfxx::onewire::bus::try_lock ( ) const

inlinenoexcept

Tries to acquire exclusive access without blocking.

Definition at line 208 of file onewire.hpp.

try_power()

result< void > idfxx::onewire::bus::try_power

(

)

Actively drives the bus high for parasitic power.

Some devices need more power than the pull-up resistor can provide during certain operations (e.g., temperature conversion).

Returns

Success, or an error on failure.

Referenced by power().

try_read() [1/2]

result< uint8_t > idfxx::onewire::bus::try_read

(

)

Reads a single byte from the bus.

Returns

The byte read, or an error on bus communication failure.

Referenced by read(), and read().

try_read() [2/2]

result< void > idfxx::onewire::bus::try_read

(

std::span< uint8_t >

buf

)

Reads multiple bytes from the bus into a buffer.

Parameters

buf	The buffer to read into.

Returns

Success, or an error on bus communication failure.

try_search() [1/2]

result< std::vector< address > > idfxx::onewire::bus::try_search

(

size_t

max_devices = 8

)

Searches for all devices on the bus.

Parameters

max_devices

Maximum number of devices to discover.

Returns

A vector of discovered device addresses, or an error on bus communication failure.

Referenced by search(), and search().

try_search() [2/2]

result< std::vector< address > > idfxx::onewire::bus::try_search	(	uint8_t	family_code,
		size_t	max_devices = 8
	)

Searches for devices with a specific family code.

Parameters

family_code	The family code to filter by (e.g., 0x28 for DS18B20).
max_devices	Maximum number of devices to discover.

Returns

A vector of discovered device addresses matching the family code, or an error on bus communication failure.

try_select()

result< void > idfxx::onewire::bus::try_select

(

address

addr

)

Selects a specific device by ROM address.

Issues a "ROM select" command on the bus. A reset() must be performed before calling this method.

Parameters

addr	The ROM address of the device to select.

Returns

Success, or an error on bus communication failure.

Referenced by select().

try_skip_rom()

result< void > idfxx::onewire::bus::try_skip_rom

(

)

Selects all devices on the bus.

Issues a "skip ROM" command. A reset() must be performed before calling this method.

Returns

Success, or an error on bus communication failure.

Referenced by skip_rom().

try_write() [1/2]

result< void > idfxx::onewire::bus::try_write

(

std::span< const uint8_t >

data

)

Writes multiple bytes to the bus.

Parameters

data	The bytes to write.

Returns

Success, or an error on bus communication failure.

try_write() [2/2]

result< void > idfxx::onewire::bus::try_write

(

uint8_t

value

)

Writes a single byte to the bus.

Parameters

value

The byte to write.

Returns

Success, or an error on bus communication failure.

Referenced by write(), and write().

unlock()

void idfxx::onewire::bus::unlock ( ) const

inline

Releases exclusive access to the bus.

Definition at line 216 of file onewire.hpp.

write() [1/2]

void idfxx::onewire::bus::write ( std::span< const uint8_t >  data )

inline

Writes multiple bytes to the bus.

Parameters

data	The bytes to write.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 305 of file onewire.hpp.

References try_write(), and idfxx::unwrap().

write() [2/2]

void idfxx::onewire::bus::write ( uint8_t  value )

inline

Writes a single byte to the bus.

Parameters

value

The byte to write.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on bus communication failure.

Definition at line 296 of file onewire.hpp.

References try_write(), and idfxx::unwrap().

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

• idfxx_onewire/include/idfxx/onewire.hpp