pcal95555::I2cInterface< Derived > Class Template Reference

CRTP-based template interface for I2C bus operations. More...

#include <pcal95555_i2c_interface.hpp>

Public Member Functions
bool	Write (uint8_t addr, uint8_t reg, const uint8_t *data, size_t len) noexcept
	Write bytes to a device register.
bool	Read (uint8_t addr, uint8_t reg, uint8_t *data, size_t len) noexcept
	Read bytes from a device register.
bool	SetAddressPins (bool a0_level, bool a1_level, bool a2_level) noexcept
bool	EnsureInitialized () noexcept
bool	RegisterInterruptHandler (std::function< void()> handler) noexcept
GPIO Pin Control
Unified interface for controlling PCAL95555 hardware control pins.
void	GpioSet (CtrlPin pin, GpioSignal signal) noexcept
	Set a control pin to the specified signal state.
bool	GpioRead (CtrlPin pin, GpioSignal &signal) noexcept
	Read the current state of a control pin.
void	GpioSetActive (CtrlPin pin) noexcept
	Assert a control pin (set to ACTIVE).
void	GpioSetInactive (CtrlPin pin) noexcept
	Deassert a control pin (set to INACTIVE).

Protected Member Functions
	I2cInterface ()=default
	Protected constructor to prevent direct instantiation.
	I2cInterface (const I2cInterface &)=delete
I2cInterface &	operator= (const I2cInterface &)=delete
	I2cInterface (I2cInterface &&)=default
I2cInterface &	operator= (I2cInterface &&)=default
	~I2cInterface ()=default
	Protected destructor.

Detailed Description

template<typename Derived>
class pcal95555::I2cInterface< Derived >

CRTP-based template interface for I2C bus operations.

This template class provides a hardware-agnostic interface for I2C communication using the CRTP pattern. Platform-specific implementations should inherit from this template with themselves as the template parameter.

Benefits of CRTP:

• Compile-time polymorphism (no virtual function overhead)
• Static dispatch instead of dynamic dispatch
• Better optimization opportunities for the compiler

Example usage:

class MyI2C : public pcal95555::I2cInterface<MyI2C> {
public:
  bool Write(...) { ... }
  bool Read(...) { ... }
};

Template Parameters

Derived

The derived class type (CRTP pattern)

Constructor & Destructor Documentation

I2cInterface() [1/3]

template<typename Derived >

pcal95555::I2cInterface< Derived >::I2cInterface ( )

protecteddefault

Protected constructor to prevent direct instantiation.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

I2cInterface() [2/3]

template<typename Derived >

pcal95555::I2cInterface< Derived >::I2cInterface ( const I2cInterface< Derived > &  )

protecteddelete

I2cInterface() [3/3]

template<typename Derived >

pcal95555::I2cInterface< Derived >::I2cInterface ( I2cInterface< Derived > &&  )

protecteddefault

~I2cInterface()

template<typename Derived >

pcal95555::I2cInterface< Derived >::~I2cInterface ( )

protecteddefault

Protected destructor.

Note

Derived classes can have public destructors

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

Member Function Documentation

EnsureInitialized()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::EnsureInitialized ( )

inlinenoexcept

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

GpioRead()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::GpioRead ( CtrlPin  pin, GpioSignal &  signal  )

inlinenoexcept

Read the current state of a control pin.

Primarily used for reading the INTN interrupt pin.

Parameters

[in]	pin	Which control pin to read.
[out]	signal	Receives the current signal state.

Returns

true if the read was successful, false otherwise.

Note

Default implementation returns false (unsupported). Override in derived class if interrupt pin monitoring is needed.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

GpioSet()

template<typename Derived >

void pcal95555::I2cInterface< Derived >::GpioSet ( CtrlPin  pin, GpioSignal  signal  )

inlinenoexcept

Set a control pin to the specified signal state.

Parameters

[in]	pin	Which control pin to drive. The chips have no output-side control pin, so the driver never calls this.
[in]	signal	ACTIVE to assert the pin function, INACTIVE to deassert.

Note

Default implementation is a no-op.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

GpioSetActive()

template<typename Derived >

void pcal95555::I2cInterface< Derived >::GpioSetActive ( CtrlPin  pin )

inlinenoexcept

Assert a control pin (set to ACTIVE).

Parameters

[in]

pin

Which control pin to assert.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

GpioSetInactive()

template<typename Derived >

void pcal95555::I2cInterface< Derived >::GpioSetInactive ( CtrlPin  pin )

inlinenoexcept

Deassert a control pin (set to INACTIVE).

Parameters

[in]

pin

Which control pin to deassert.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

operator=() [1/2]

template<typename Derived >

I2cInterface & pcal95555::I2cInterface< Derived >::operator= ( const I2cInterface< Derived > &  )

protecteddelete

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

operator=() [2/2]

template<typename Derived >

I2cInterface & pcal95555::I2cInterface< Derived >::operator= ( I2cInterface< Derived > &&  )

protecteddefault

Read()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::Read ( uint8_t  addr, uint8_t  reg, uint8_t *  data, size_t  len  )

inlinenoexcept

Read bytes from a device register.

Parameters

addr	7-bit I2C address of the target device.
reg	Register address to read from.
data	Pointer to the buffer to store received data.
len	Number of bytes to read into the buffer.

Returns

true if the read succeeds; false on NACK or error.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

RegisterInterruptHandler()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::RegisterInterruptHandler ( std::function< void()>  handler )

inlinenoexcept

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

SetAddressPins()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::SetAddressPins ( bool  a0_level, bool  a1_level, bool  a2_level  )

inlinenoexcept

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

Write()

template<typename Derived >

bool pcal95555::I2cInterface< Derived >::Write ( uint8_t  addr, uint8_t  reg, const uint8_t *  data, size_t  len  )

inlinenoexcept

Write bytes to a device register.

Parameters

addr	7-bit I2C address of the target device.
reg	Register address to write to.
data	Pointer to the data buffer containing bytes to send.
len	Number of bytes to write from the buffer.

Returns

true if the device acknowledges the transfer; false on NACK or error.

Examples

/home/runner/work/hf-pcal95555-driver/hf-pcal95555-driver/inc/pcal95555_i2c_interface.hpp.

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

• pcal95555_i2c_interface.hpp