SPIS driver

Serial Peripheral Interface Slave with EasyDMA (SPIS) driver. More...

Modules
	SPIS peripheral driver configuration

Data Structures
struct	nrfx_spis_t
	Data structure for the Serial Peripheral Interface Slave with EasyDMA (SPIS) driver instance. More...
struct	nrfx_spis_evt_t
	SPI slave driver event structure. More...
struct	nrfx_spis_config_t
	SPI peripheral device configuration data. More...

Macros
#define	NRFX_SPIS_INSTANCE(id)
	Macro for creating an instance of the SPI slave driver. More...
#define	NRFX_SPIS_PIN_NOT_USED   0xFF
	This value can be provided instead of a pin number for the signals MOSI and MISO to specify that the given signal is not used and therefore does not need to be connected to a pin.
#define	NRFX_SPIS_DEFAULT_CONFIG(_pin_sck, _pin_mosi, _pin_miso, _pin_csn)
	SPIS driver default configuration. More...

Typedefs
typedef void(*	nrfx_spis_event_handler_t) (nrfx_spis_evt_t const *p_event, void *p_context)
	SPI slave driver event handler type. More...

Enumerations
enum	nrfx_spis_evt_type_t {   NRFX_SPIS_BUFFERS_SET_DONE,   NRFX_SPIS_XFER_DONE,   NRFX_SPIS_EVT_TYPE_MAX }
	SPI slave driver event types. More...

Functions
nrfx_err_t	nrfx_spis_init (nrfx_spis_t const *p_instance, nrfx_spis_config_t const *p_config, nrfx_spis_event_handler_t event_handler, void *p_context)
	Function for initializing the SPI slave driver instance. More...
void	nrfx_spis_uninit (nrfx_spis_t const *p_instance)
	Function for uninitializing the SPI slave driver instance. More...
nrfx_err_t	nrfx_spis_buffers_set (nrfx_spis_t const *p_instance, uint8_t const *p_tx_buffer, size_t tx_buffer_length, uint8_t *p_rx_buffer, size_t rx_buffer_length)
	Function for preparing the SPI slave instance for a single SPI transaction. More...

Detailed Description

Serial Peripheral Interface Slave with EasyDMA (SPIS) driver.

Macro Definition Documentation

NRFX_SPIS_DEFAULT_CONFIG

#define NRFX_SPIS_DEFAULT_CONFIG	(		_pin_sck,
			_pin_mosi,
			_pin_miso,
			_pin_csn
	)

Value:

{ \
 .miso_pin = _pin_miso, \
 .mosi_pin = _pin_mosi, \
 .sck_pin = _pin_sck, \
 .csn_pin = _pin_csn, \
 .mode = NRF_SPIS_MODE_0, \
 .bit_order = NRF_SPIS_BIT_ORDER_MSB_FIRST, \
 .csn_pullup = NRF_GPIO_PIN_NOPULL, \
 .miso_drive = NRF_GPIO_PIN_S0S1, \
 .def = 0xFF, \
 .orc = 0xFE, \
 .irq_priority = NRFX_SPIS_DEFAULT_CONFIG_IRQ_PRIORITY, \
}

SPIS driver default configuration.

This configuration sets up SPIS with the following options:

• mode: 0 (SCK active high, sample on leading edge of the clock signal)
• MSB shifted out first
• CSN pull-up disabled
• MISO pin drive set to standard '0' and standard '1'
• default character set to 0xFF
• over-read character set to 0xFE

Parameters

[in]	_pin_sck	SCK pin.
[in]	_pin_mosi	MOSI pin.
[in]	_pin_miso	MISO pin.
[in]	_pin_csn	CSN pin.

NRFX_SPIS_INSTANCE

#define NRFX_SPIS_INSTANCE

(

id

)

Value:

{ \
 .p_reg = NRFX_CONCAT_2(NRF_SPIS, id), \
 .drv_inst_idx = NRFX_CONCAT_3(NRFX_SPIS, id, _INST_IDX), \
}

Macro for creating an instance of the SPI slave driver.

Typedef Documentation

nrfx_spis_event_handler_t

typedef void(* nrfx_spis_event_handler_t) (nrfx_spis_evt_t const *p_event, void *p_context)

SPI slave driver event handler type.

Parameters

[in]	p_event	Pointer to the event structure. The structure is allocated on the stack so it is valid only until the event handler returns.
[in]	p_context	Context set on initialization.

Enumeration Type Documentation

nrfx_spis_evt_type_t

enum nrfx_spis_evt_type_t

SPI slave driver event types.

Enumerator
NRFX_SPIS_BUFFERS_SET_DONE	Memory buffer set event. Memory buffers have been set successfully to the SPI slave device, and SPI transaction can be done.
NRFX_SPIS_XFER_DONE	SPI transaction event. SPI transaction has been completed.
NRFX_SPIS_EVT_TYPE_MAX	Enumeration upper bound.

Function Documentation

nrfx_spis_buffers_set()

nrfx_err_t nrfx_spis_buffers_set	(	nrfx_spis_t const *	p_instance,
		uint8_t const *	p_tx_buffer,
		size_t	tx_buffer_length,
		uint8_t *	p_rx_buffer,
		size_t	rx_buffer_length
	)

Function for preparing the SPI slave instance for a single SPI transaction.

This function prepares the SPI slave device to be ready for a single SPI transaction. It configures the SPI slave device to use the memory supplied with the function call in SPI transactions.

When either the memory buffer configuration or the SPI transaction has been completed, the event callback function will be called with the appropriate event nrfx_spis_evt_type_t. The callback function can be called before returning from this function, because it is called from the SPI slave interrupt context.

Note

This function can be called from the callback function context.

Client applications must call this function after every NRFX_SPIS_XFER_DONE event if the SPI slave driver must be prepared for a possible new SPI transaction.

Peripherals using EasyDMA (including SPIS) require the transfer buffers to be placed in the Data RAM region. If this condition is not met, this function will fail with the error code NRFX_ERROR_INVALID_ADDR.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	p_tx_buffer	Pointer to the TX buffer. Can be NULL when the buffer length is zero.
[in]	p_rx_buffer	Pointer to the RX buffer. Can be NULL when the buffer length is zero.
[in]	tx_buffer_length	Length of the TX buffer in bytes.
[in]	rx_buffer_length	Length of the RX buffer in bytes.

Return values

NRFX_SUCCESS	The operation was successful.
NRFX_ERROR_INVALID_STATE	The operation failed because the SPI slave device is in an incorrect state.
NRFX_ERROR_INVALID_ADDR	The provided buffers are not placed in the Data RAM region.
NRFX_ERROR_INVALID_LENGTH	Provided lengths exceed the EasyDMA limits for the peripheral.
NRFX_ERROR_INTERNAL	The operation failed because of an internal error.

nrfx_spis_init()

nrfx_err_t nrfx_spis_init	(	nrfx_spis_t const *	p_instance,
		nrfx_spis_config_t const *	p_config,
		nrfx_spis_event_handler_t	event_handler,
		void *	p_context
	)

Function for initializing the SPI slave driver instance.

Note

When the nRF52 Anomaly 109 workaround for SPIS is enabled, this function initializes the GPIOTE driver as well, and uses one of GPIOTE channels to detect falling edges on CSN pin.

Parameters

[in]	p_instance	Pointer to the driver instance structure.
[in]	p_config	Pointer to the structure with the initial configuration.
[in]	event_handler	Function to be called by the SPI slave driver upon event. Must not be NULL.
[in]	p_context	Context passed to the event handler.

Return values

NRFX_SUCCESS	The initialization was successful.
NRFX_ERROR_INVALID_STATE	The instance is already initialized.
NRFX_ERROR_INVALID_PARAM	Invalid parameter is supplied.
NRFX_ERROR_BUSY	Some other peripheral with the same instance ID is already in use. This is possible only if Peripheral Resource Sharing (PRS) module is enabled.
NRFX_ERROR_INTERNAL	GPIOTE channel for detecting falling edges on CSN pin cannot be initialized. Possible only when using nRF52 Anomaly 109 workaround.

nrfx_spis_uninit()

void nrfx_spis_uninit

(

nrfx_spis_t const *

p_instance

)

Function for uninitializing the SPI slave driver instance.

Parameters

[in]

p_instance

Pointer to the driver instance structure.