m5::unit::RS485Component Class Reference

Non-instantiable base class for RS-485 transceiver units. More...

#include <rs485_component.hpp>

Inheritance diagram for m5::unit::RS485Component:

Classes
struct	byteswap_float_tag
struct	byteswap_int_tag
struct	byteswap_none_tag
struct	byteswap_tag_of
struct	config_t
	Settings for begin. More...

Public Member Functions
virtual	~RS485Component ()=default
	Destructor.
virtual bool	begin () override
	Begin using the registered UART adapter.
Settings for begin
config_t	config ()
	Gets the configuration.
void	config (const config_t &cfg)
	Sets the configuration.
Arduino Serial Compatibility API
Note See also Arduino documents
	operator bool () const
	Returns true if the unit is registered.
int	available ()
	Returns the number of available bytes to read.
int	availableForWrite ()
	Returns the number of bytes that can be written without blocking.
int	peek ()
	Peeks the next incoming byte without removing it.
int	read ()
	Reads one byte.
size_t	read (uint8_t *buffer, const size_t size)
	Reads up to size bytes into buffer.
size_t	read (char *buffer, const size_t size)
	Reads up to size bytes into buffer.
size_t	readBytes (uint8_t *buffer, const size_t length)
	Reads bytes with timeout defined by underlying Serial.
size_t	readBytes (char *buffer, const size_t length)
	Reads bytes with timeout defined by underlying Serial.
void	flush ()
	Flushes the serial port.
void	flush (const bool txOnly)
	Flushes the serial port.
size_t	write (const uint8_t d, const bool flush=true)
	Writes one byte.
size_t	write (const uint8_t *buffer, const size_t size, const bool flush=true)
	Writes bytes from buffer.
size_t	write (const char *buffer, const size_t size, const bool flush=true)
	Writes bytes from buffer.
size_t	write (const char *s, const bool flush=true)
	Writes a null-terminated string.
Read/Write a trivially copyable value
template<typename T , bool LittleEndian = true>
bool	readValue (T &value)
	Read a trivially copyable value.
template<typename T , bool LittleEndian = true>
bool	writeValue (const T value)
	Write a trivially copyable value.

Protected Member Functions
	RS485Component (const uint8_t addr)
	Base constructor (concrete subclasses pass their DEFAULT_ADDRESS)
ISerial *	iserial ()
virtual std::unique_ptr< ISerial >	make_serial (AdapterUART *ad)
	Factory hook: build the concrete ISerial to be used by begin().

Static Protected Member Functions
template<typename T >
static T	byteswap_if_needed (T v)
template<typename T >
static T	byteswap_if_needed_impl (T v, byteswap_int_tag)
template<typename T >
static T	byteswap_if_needed_impl (T v, byteswap_float_tag)
template<typename T >
static T	byteswap_if_needed_impl (T v, byteswap_none_tag)

Protected Attributes
std::unique_ptr< ISerial >	_serial {}
config_t	_cfg {}

Detailed Description

Non-instantiable base class for RS-485 transceiver units.

Member Function Documentation

available()

int m5::unit::RS485Component::available ( )

inline

Returns the number of available bytes to read.

Returns

Number of bytes available

availableForWrite()

int m5::unit::RS485Component::availableForWrite ( )

inline

Returns the number of bytes that can be written without blocking.

Returns

Number of bytes available for write

begin()

bool m5::unit::RS485Component::begin ( )

overridevirtual

Begin using the registered UART adapter.

Returns

True if the adapter is valid and ready

Reimplemented in m5::unit::UnitSIT3088.

config() [1/2]

config_t m5::unit::RS485Component::config ( )

inline

Gets the configuration.

Returns

Current configuration

config() [2/2]

void m5::unit::RS485Component::config ( const config_t & cfg )

inline

Sets the configuration.

Parameters

cfg	Configuration settings

flush()

void m5::unit::RS485Component::flush ( const bool txOnly )

inline

Flushes the serial port.

Parameters

txOnly

If true, flush only TX

make_serial()

std::unique_ptr< RS485Component::ISerial > m5::unit::RS485Component::make_serial ( AdapterUART * ad )

protectedvirtual

Factory hook: build the concrete ISerial to be used by begin().

Parameters

ad	AdapterUART obtained via asAdapter<AdapterUART>() (never null at call site)

Returns

Owning pointer to the ISerial implementation, or a null-behavior implementation on frameworks not yet supported.

Note

Default implementation wraps the Arduino HardwareSerial exposed by the adapter. Chip-specific subclasses (e.g. UnitSIT3088) override to install a decorator that adds direction-pin control, etc.

Reimplemented in m5::unit::UnitSIT3088.

peek()

int m5::unit::RS485Component::peek ( )

inline

Peeks the next incoming byte without removing it.

Returns

Next byte or -1 if none

read() [1/3]

int m5::unit::RS485Component::read ( )

inline

Reads one byte.

Returns

Byte read or -1 if none

read() [2/3]

size_t m5::unit::RS485Component::read ( char * buffer, const size_t size )

inline

Reads up to size bytes into buffer.

Parameters

buffer	Destination buffer
size	Maximum number of bytes to read

Returns

Number of bytes read

read() [3/3]

size_t m5::unit::RS485Component::read ( uint8_t * buffer, const size_t size )

inline

Reads up to size bytes into buffer.

Parameters

buffer	Destination buffer
size	Maximum number of bytes to read

Returns

Number of bytes read

readBytes() [1/2]

size_t m5::unit::RS485Component::readBytes ( char * buffer, const size_t length )

inline

Reads bytes with timeout defined by underlying Serial.

Parameters

buffer	Destination buffer
length	Number of bytes to read

Returns

Number of bytes actually read

readBytes() [2/2]

size_t m5::unit::RS485Component::readBytes ( uint8_t * buffer, const size_t length )

inline

Reads bytes with timeout defined by underlying Serial.

Parameters

buffer	Destination buffer
length	Number of bytes to read

Returns

Number of bytes actually read

readValue()

template<typename T , bool LittleEndian = true>

bool m5::unit::RS485Component::readValue ( T & value )

inline

Read a trivially copyable value.

Template Parameters

T	Type (must be trivially copyable and standard-layout)
LittleEndian	Incoming data is little-endian if true

Parameters

value

Receive variable

Returns

True if successful

Note

LittleEndian byteswap is applied for integral / enum types and for 32-bit / 64-bit floating-point types (via bit-cast). Aggregate / struct types are stored as-is in host byte order; the LittleEndian parameter is ignored for those.

LittleEndian only declares the wire byte order; the peer must agree on the same convention. Floating-point special values (NaN, +/-inf, +/-0) are byte-reversed as raw bit patterns without special-casing.

write() [1/4]

size_t m5::unit::RS485Component::write	(	const char *	buffer,
		const size_t	size,
		const bool	flush = true )

Writes bytes from buffer.

Parameters

buffer	Source buffer
size	Number of bytes to write
flush	If true, flush TX before returning

Returns

Number of bytes written

write() [2/4]

size_t m5::unit::RS485Component::write	(	const char *	s,
		const bool	flush = true )

Writes a null-terminated string.

Parameters

s	Null-terminated string
flush	If true, flush TX before returning

Returns

Number of bytes written

write() [3/4]

size_t m5::unit::RS485Component::write	(	const uint8_t *	buffer,
		const size_t	size,
		const bool	flush = true )

Writes bytes from buffer.

Parameters

buffer	Source buffer
size	Number of bytes to write
flush	If true, flush TX before returning

Returns

Number of bytes written

write() [4/4]

size_t m5::unit::RS485Component::write	(	const uint8_t	d,
		const bool	flush = true )

Writes one byte.

Parameters

d	Byte to write
flush	If true, flush TX before returning

Returns

Number of bytes written

writeValue()

template<typename T , bool LittleEndian = true>

bool m5::unit::RS485Component::writeValue ( const T value )

inline

Write a trivially copyable value.

Template Parameters

T	Type (must be trivially copyable and standard-layout)
LittleEndian	Outgoing data is little-endian if true

Parameters

value

Value to write

Returns

True if successful

Note

LittleEndian byteswap is applied for integral / enum types and for 32-bit / 64-bit floating-point types (via bit-cast). Aggregate / struct types are sent as-is in host byte order; the LittleEndian parameter is ignored for those.

LittleEndian only declares the wire byte order; the peer must agree on the same convention. Floating-point special values (NaN, +/-inf, +/-0) are byte-reversed as raw bit patterns without special-casing.