CRTP-based template interface for SPI communication. More...

#include <max22200_spi_interface.hpp>

Public Member Functions
bool	Initialize ()
	Initialize the SPI interface.

bool	Transfer (const uint8_t tx_data, uint8_t rx_data, size_t length)
	Transfer data over SPI interface.

void	SetChipSelect (bool state)
	Set chip select state.

bool	Configure (uint32_t speed_hz, uint8_t mode, bool msb_first=true)
	Configure SPI parameters.

bool	IsReady () const
	Check if SPI interface is ready.

void	DelayUs (uint32_t us)
	Blocking delay in microseconds (from comm/CRTP implementation).

GPIO Pin Control
Unified interface for controlling MAX22200 hardware control pins. The platform bus implementation maps GpioSignal::ACTIVE/INACTIVE to the correct physical level for each pin based on its polarity.
void	GpioSet (CtrlPin pin, GpioSignal signal)
	Set a control pin to the specified signal state.

bool	GpioRead (CtrlPin pin, GpioSignal &signal)
	Read the current state of a control pin.

void	GpioSetActive (CtrlPin pin)
	Assert a control pin (set to ACTIVE). Convenience wrapper for `GpioSet(pin, GpioSignal::ACTIVE)`.

void	GpioSetInactive (CtrlPin pin)
	Deassert a control pin (set to INACTIVE). Convenience wrapper for `GpioSet(pin, GpioSignal::INACTIVE)`.

Protected Member Functions
	SpiInterface ()=default
	Protected constructor to prevent direct instantiation.

	SpiInterface (const SpiInterface &)=delete

SpiInterface &	operator= (const SpiInterface &)=delete

	SpiInterface (SpiInterface &&)=default

SpiInterface &	operator= (SpiInterface &&)=default

	~SpiInterface ()=default
	Protected destructor.

Detailed Description

template<typename Derived>
class max22200::SpiInterface< Derived >

CRTP-based template interface for SPI communication.

This template class provides a hardware-agnostic interface for SPI 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 MySPI : public max22200::SpiInterface<MySPI> {
public:
  bool Initialize() { ... }
  bool Transfer(...) { ... }
  // ... implement other methods
};

Template Parameters

Derived The derived class type (CRTP pattern)

Constructor & Destructor Documentation

◆ SpiInterface() [1/3]

template<typename Derived >

max22200::SpiInterface< Derived >::SpiInterface ( )

protecteddefault

Protected constructor to prevent direct instantiation.

◆ SpiInterface() [2/3]

template<typename Derived >

max22200::SpiInterface< Derived >::SpiInterface ( const SpiInterface< Derived > & )

protecteddelete

◆ SpiInterface() [3/3]

template<typename Derived >

max22200::SpiInterface< Derived >::SpiInterface ( SpiInterface< Derived > && )

protecteddefault

◆ ~SpiInterface()

template<typename Derived >

max22200::SpiInterface< Derived >::~SpiInterface ( )

protecteddefault

Protected destructor.

Note: Derived classes can have public destructors

Member Function Documentation

◆ Configure()

template<typename Derived >

bool max22200::SpiInterface< Derived >::Configure	(	uint32_t	speed_hz,
		uint8_t	mode,
		bool	msb_first = true )

inline

Configure SPI parameters.

Sets up SPI communication parameters such as clock speed, data mode, and bit order.

Parameters

speed_hz	SPI clock speed in Hz Standalone: Up to 10 MHz Daisy-chain: Up to 5 MHz Minimum period: 100ns (10 MHz max)
mode	SPI mode (0-3) defining clock polarity and phase Must be Mode 0 (CPOL=0, CPHA=0) for MAX22200 Clock idle LOW, data sampled on rising edge
msb_first	true for MSB first, false for LSB first Must be true (MSB first) for MAX22200

Returns: true if configuration was successful, false otherwise

Note: MAX22200 requires Mode 0 and MSB-first bit order.; Clock speed should not exceed 10 MHz (standalone) or 5 MHz (daisy-chain).

◆ DelayUs()

template<typename Derived >

void max22200::SpiInterface< Derived >::DelayUs ( uint32_t us )

inline

Blocking delay in microseconds (from comm/CRTP implementation).

Used for device timing requirements, e.g. MAX22200 power-up delay (0.5 ms after ENABLE) before first SPI access. Platform implements the actual wait (e.g. esp_rom_delay_us, or RTOS-aware delay).

Parameters

us	Delay duration in microseconds.

◆ GpioRead()

template<typename Derived >

bool max22200::SpiInterface< Derived >::GpioRead	(	CtrlPin	pin,
		GpioSignal &	signal )

inline

Read the current state of a control pin.

Primarily used for reading the FAULT pin status to detect fault conditions.

Parameters

[in]	pin	Which control pin to read: FAULT: Active-low (ACTIVE = LOW = fault present) ENABLE: Can be read to verify state CMD: Can be read to verify state
[out]	signal	Receives the current signal state: GpioSignal::ACTIVE = fault present (for FAULT pin) GpioSignal::INACTIVE = no fault (for FAULT pin)

Returns: true if the read was successful, false otherwise.

Note: FAULT pin is open-drain and requires external pullup resistor.; FAULT pin is LOW when any unmasked fault is active.; Reading FAULT pin does not clear fault flags (use ReadFaultRegister()).

◆ GpioSet()

template<typename Derived >

void max22200::SpiInterface< Derived >::GpioSet	(	CtrlPin	pin,
		GpioSignal	signal )

inline

Set a control pin to the specified signal state.

Controls the MAX22200 hardware control pins (ENABLE, CMD, FAULT). The platform implementation maps GpioSignal::ACTIVE/INACTIVE to the correct physical level based on each pin's polarity.

Parameters

[in]	pin	Which control pin to drive: ENABLE: Active-high (ACTIVE = HIGH, enables device) CMD: Active-high (ACTIVE = HIGH, Command Register mode) FAULT: Read-only (use GpioRead instead)
[in]	signal	ACTIVE to assert the pin function, INACTIVE to deassert.

Note: For CMD pin: Must be held HIGH during Command Register writes.; For ENABLE pin: 0.5ms delay required after setting HIGH before SPI access.; FAULT pin is read-only (open-drain output from device).

See also: GpioSetActive(), GpioSetInactive() for convenience wrappers

◆ GpioSetActive()

template<typename Derived >

void max22200::SpiInterface< Derived >::GpioSetActive ( CtrlPin pin )

inline

Assert a control pin (set to ACTIVE). Convenience wrapper for GpioSet(pin, GpioSignal::ACTIVE).

Parameters

[in] pin Which control pin to assert.

◆ GpioSetInactive()

template<typename Derived >

void max22200::SpiInterface< Derived >::GpioSetInactive ( CtrlPin pin )

inline

Deassert a control pin (set to INACTIVE). Convenience wrapper for GpioSet(pin, GpioSignal::INACTIVE).

Parameters

[in] pin Which control pin to deassert.

◆ Initialize()

template<typename Derived >

bool max22200::SpiInterface< Derived >::Initialize ( )

inline

Initialize the SPI interface.

This method should perform any necessary initialization of the SPI hardware, including setting up clock rates, modes, and other configuration parameters.

Returns: true if initialization was successful, false otherwise

◆ IsReady()

template<typename Derived >

bool max22200::SpiInterface< Derived >::IsReady ( ) const

inline

Check if SPI interface is ready.

Verifies that the SPI interface is properly initialized and ready for communication.

Returns: true if interface is ready, false otherwise

◆ operator=() [1/2]

template<typename Derived >

SpiInterface & max22200::SpiInterface< Derived >::operator= ( const SpiInterface< Derived > & )

protecteddelete

◆ operator=() [2/2]

template<typename Derived >

SpiInterface & max22200::SpiInterface< Derived >::operator= ( SpiInterface< Derived > && )

protecteddefault

◆ SetChipSelect()

template<typename Derived >

void max22200::SpiInterface< Derived >::SetChipSelect ( bool state )

inline

Set chip select state.

Controls the chip select (CS) line for the SPI device.

Parameters

state true to assert CS (active low), false to deassert

Note: The actual polarity of CS depends on hardware implementation. This method should handle the correct CS polarity internally.

◆ Transfer()

template<typename Derived >

bool max22200::SpiInterface< Derived >::Transfer	(	const uint8_t *	tx_data,
		uint8_t *	rx_data,
		size_t	length )

inline

Transfer data over SPI interface.

Performs a full-duplex SPI transfer. The method should handle both transmission and reception of data simultaneously.

Parameters

tx_data	Pointer to data buffer to transmit
rx_data	Pointer to buffer for received data (can be same as tx_data)
length	Number of bytes to transfer

Returns: true if transfer was successful, false otherwise

Note: Both tx_data and rx_data must be valid pointers and length must be greater than 0 for a successful transfer.

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

inc/max22200_spi_interface.hpp

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ SpiInterface() [1/3]

◆ SpiInterface() [2/3]

◆ SpiInterface() [3/3]

◆ ~SpiInterface()

Member Function Documentation

◆ Configure()

◆ DelayUs()

◆ GpioRead()

◆ GpioSet()

◆ GpioSetActive()

◆ GpioSetInactive()

◆ Initialize()

◆ IsReady()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ SetChipSelect()

◆ Transfer()