spi.h File Reference

Serial Peripheral Interface (SPI) driver for SAM.

Copyright (c) 2011-2018 Microchip Technology Inc. and its subsidiaries.

#include "compiler.h"

Macros
#define	spi_get_pcs(chip_sel_id)   ((~(1u<<(chip_sel_id)))&0xF)
	Generate Peripheral Chip Select Value from Chip Select ID. More...
#define	SPI_TIMEOUT   15000
	Time-out value (number of attempts). More...

Typedefs
typedef enum spi_cs_behavior	spi_cs_behavior_t
	SPI Chip Select behavior modes while transferring. More...

Enumerations
enum	spi_cs_behavior {   SPI_CS_KEEP_LOW = SPI_CSR_CSAAT,   SPI_CS_RISE_NO_TX = 0,   SPI_CS_RISE_FORCED = SPI_CSR_CSNAAT }
	SPI Chip Select behavior modes while transferring. More...
enum	spi_status_t {   SPI_ERROR = -1,   SPI_OK = 0,   SPI_ERROR_TIMEOUT = 1,   SPI_ERROR_ARGUMENT,   SPI_ERROR_OVERRUN,   SPI_ERROR_MODE_FAULT,   SPI_ERROR_OVERRUN_AND_MODE_FAULT }
	Status codes used by the SPI driver. More...

Functions
int16_t	spi_calc_baudrate_div (const uint32_t baudrate, uint32_t mck)
	Calculate the baudrate divider. More...
void	spi_configure_cs_behavior (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_cs_behavior)
	Configure CS behavior for SPI transfer (spi_cs_behavior_t). More...
static void	spi_disable (Spi *p_spi)
	Disable SPI. More...
void	spi_disable_clock (Spi *p_spi)
	Disable SPI clock. More...
static void	spi_disable_interrupt (Spi *p_spi, uint32_t ul_sources)
	Disable SPI interrupts. More...
static void	spi_disable_loopback (Spi *p_spi)
	Disable loopback mode. More...
static void	spi_disable_mode_fault_detect (Spi *p_spi)
	Disable Mode Fault Detection. More...
static void	spi_disable_peripheral_select_decode (Spi *p_spi)
	Disable Peripheral Select Decode. More...
static void	spi_disable_tx_on_rx_empty (Spi *p_spi)
	Disable waiting RX_EMPTY before transfer starts. More...
static void	spi_enable (Spi *p_spi)
	Enable SPI. More...
void	spi_enable_clock (Spi *p_spi)
	Enable SPI clock. More...
static void	spi_enable_interrupt (Spi *p_spi, uint32_t ul_sources)
	Enable SPI interrupts. More...
static void	spi_enable_loopback (Spi *p_spi)
	Enable loopback mode. More...
static void	spi_enable_mode_fault_detect (Spi *p_spi)
	Enable Mode Fault Detection. More...
static void	spi_enable_peripheral_select_decode (Spi *p_spi)
	Enable Peripheral Select Decode. More...
static void	spi_enable_tx_on_rx_empty (Spi *p_spi)
	Enable waiting RX_EMPTY before transfer starts. More...
static uint16_t	spi_get (Spi *p_spi)
	Get one data to a SPI peripheral. More...
static uint32_t	spi_get_mode (Spi *p_spi)
	Get SPI work mode. More...
static uint32_t	spi_get_mode_fault_detect_setting (Spi *p_spi)
	Check if mode fault detection is enabled. More...
static Pdc *	spi_get_pdc_base (Spi *p_spi)
	Get PDC registers base address. More...
static uint32_t	spi_get_peripheral_select_decode_setting (Spi *p_spi)
	Get Peripheral Select Decode mode. More...
static uint32_t	spi_get_peripheral_select_mode (Spi *p_spi)
	Get Peripheral Select mode. More...
static void *	spi_get_rx_access (Spi *p_spi)
	Get receive data register address for DMA operation. More...
static void *	spi_get_tx_access (Spi *p_spi)
	Get transmit data register address for DMA operation. More...
static uint32_t	spi_get_tx_on_rx_empty_setting (Spi *p_spi)
	Check if SPI waits RX_EMPTY before transfer starts. More...
uint32_t	spi_get_writeprotect_status (Spi *p_spi)
	Indicate write protect status. More...
static uint32_t	spi_is_enabled (Spi *p_spi)
	Test if the SPI is enabled. More...
static uint32_t	spi_is_rx_full (Spi *p_spi)
	Check if the SPI contains a received character. More...
static uint32_t	spi_is_rx_ready (Spi *p_spi)
	Check if all receptions are ready. More...
static uint32_t	spi_is_tx_empty (Spi *p_spi)
	Check if all transmissions are complete. More...
static uint32_t	spi_is_tx_ready (Spi *p_spi)
	Check if all transmissions are ready. More...
static void	spi_put (Spi *p_spi, uint16_t data)
	Put one data to a SPI peripheral. More...
spi_status_t	spi_read (Spi *p_spi, uint16_t *us_data, uint8_t *p_pcs)
	Read the received data and it's peripheral chip select value. More...
static uint32_t	spi_read_interrupt_mask (Spi *p_spi)
	Read SPI interrupt mask. More...
static uint32_t	spi_read_status (Spi *p_spi)
	Read status register. More...
static void	spi_reset (Spi *p_spi)
	Reset SPI and set it to Slave mode. More...
int16_t	spi_set_baudrate_div (Spi *p_spi, uint32_t ul_pcs_ch, uint8_t uc_baudrate_divider)
	Set Serial Clock Baud Rate divider value (SCBR). More...
void	spi_set_bits_per_transfer (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_bits)
	Set number of bits per transfer. More...
void	spi_set_clock_phase (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_phase)
	Set Data Capture Phase. More...
void	spi_set_clock_polarity (Spi *p_spi, uint32_t ul_pcs_ch, uint32_t ul_polarity)
	Set clock default state. More...
void	spi_set_delay_between_chip_select (Spi *p_spi, uint32_t ul_delay)
	Set delay between chip selects (in number of MCK clocks). More...
static void	spi_set_fixed_peripheral_select (Spi *p_spi)
	Set Fixed Peripheral Select. More...
static void	spi_set_lastxfer (Spi *p_spi)
	Issue a LASTXFER command. More...
static void	spi_set_master_mode (Spi *p_spi)
	Set SPI to Master mode. More...
void	spi_set_peripheral_chip_select_value (Spi *p_spi, uint32_t ul_value)
	Set Peripheral Chip Select (PCS) value. More...
static void	spi_set_slave_mode (Spi *p_spi)
	Set SPI to Slave mode. More...
void	spi_set_transfer_delay (Spi *p_spi, uint32_t ul_pcs_ch, uint8_t uc_dlybs, uint8_t uc_dlybct)
	Configure timing for SPI transfer. More...
static void	spi_set_variable_peripheral_select (Spi *p_spi)
	Set Variable Peripheral Select. More...
void	spi_set_writeprotect (Spi *p_spi, uint32_t ul_enable)
	Enable or disable write protection of SPI registers. More...
spi_status_t	spi_write (Spi *p_spi, uint16_t us_data, uint8_t uc_pcs, uint8_t uc_last)
	Write the transmitted data with specified peripheral chip select value. More...

#define spi_get_pcs

(

chip_sel_id

)

((~(1u<<(chip_sel_id)))&0xF)

Generate Peripheral Chip Select Value from Chip Select ID.

Note

When chip select n is working, PCS bit n is set to low level.

Parameters

chip_sel_id

The chip select number used

Referenced by spi_master_initialize(), and spi_slave_initialize().

#define SPI_TIMEOUT   15000

Time-out value (number of attempts).

Referenced by spi_read(), and spi_write().

typedef enum spi_cs_behavior spi_cs_behavior_t

SPI Chip Select behavior modes while transferring.

enum spi_cs_behavior

SPI Chip Select behavior modes while transferring.

Enumerator
SPI_CS_KEEP_LOW	CS does not rise until a new transfer is requested on different chip select.
SPI_CS_RISE_NO_TX	CS rises if there is no more data to transfer.
SPI_CS_RISE_FORCED	CS is de-asserted systematically during a time DLYBCS.

enum spi_status_t

Status codes used by the SPI driver.

Enumerator
SPI_ERROR
SPI_OK
SPI_ERROR_TIMEOUT
SPI_ERROR_ARGUMENT
SPI_ERROR_OVERRUN
SPI_ERROR_MODE_FAULT
SPI_ERROR_OVERRUN_AND_MODE_FAULT

static void spi_disable ( Spi *  p_spi )

inlinestatic

Disable SPI.

Note

CS is de-asserted, which indicates that the last data is done, and user should check TX_EMPTY before disabling SPI.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize(), and spi_slave_initialize().

static void spi_disable_interrupt ( Spi *  p_spi, uint32_t  ul_sources  )

inlinestatic

Disable SPI interrupts.

Parameters

p_spi	Pointer to an SPI instance.
ul_sources	Interrupts to be disabled.

static void spi_disable_loopback ( Spi *  p_spi )

inlinestatic

Disable loopback mode.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_disable_mode_fault_detect ( Spi *  p_spi )

inlinestatic

Disable Mode Fault Detection.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize(), and spi_slave_initialize().

static void spi_disable_peripheral_select_decode ( Spi *  p_spi )

inlinestatic

Disable Peripheral Select Decode.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_disable_tx_on_rx_empty ( Spi *  p_spi )

inlinestatic

Disable waiting RX_EMPTY before transfer starts.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_enable ( Spi *  p_spi )

inlinestatic

Enable SPI.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize(), and spi_slave_initialize().

static void spi_enable_interrupt ( Spi *  p_spi, uint32_t  ul_sources  )

inlinestatic

Enable SPI interrupts.

Parameters

p_spi	Pointer to an SPI instance.
ul_sources	Interrupts to be enabled.

static void spi_enable_loopback ( Spi *  p_spi )

inlinestatic

Enable loopback mode.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_enable_mode_fault_detect ( Spi *  p_spi )

inlinestatic

Enable Mode Fault Detection.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_enable_peripheral_select_decode ( Spi *  p_spi )

inlinestatic

Enable Peripheral Select Decode.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_enable_tx_on_rx_empty ( Spi *  p_spi )

inlinestatic

Enable waiting RX_EMPTY before transfer starts.

Parameters

p_spi

Pointer to an SPI instance.

static uint16_t spi_get ( Spi *  p_spi )

inlinestatic

Get one data to a SPI peripheral.

Parameters

p_spi

Base address of the SPI instance.

Returns

The data byte

static uint32_t spi_get_mode ( Spi *  p_spi )

inlinestatic

Get SPI work mode.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 for master mode, 0 for slave mode.

static uint32_t spi_get_mode_fault_detect_setting ( Spi *  p_spi )

inlinestatic

Check if mode fault detection is enabled.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 for disabled, 0 for enabled.

static Pdc* spi_get_pdc_base ( Spi *  p_spi )

inlinestatic

Get PDC registers base address.

Parameters

p_spi

Pointer to an SPI instance.

Returns

PDC registers base for PDC driver to access.

static uint32_t spi_get_peripheral_select_decode_setting ( Spi *  p_spi )

inlinestatic

Get Peripheral Select Decode mode.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 for decode mode, 0 for direct mode.

static uint32_t spi_get_peripheral_select_mode ( Spi *  p_spi )

inlinestatic

Get Peripheral Select mode.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 for Variable mode, 0 for fixed mode.

Referenced by spi_read(), and spi_write().

static void* spi_get_rx_access ( Spi *  p_spi )

inlinestatic

Get receive data register address for DMA operation.

Parameters

p_spi

Pointer to an SPI instance.

Returns

Receive address for DMA access.

static void* spi_get_tx_access ( Spi *  p_spi )

inlinestatic

Get transmit data register address for DMA operation.

Parameters

p_spi

Pointer to an SPI instance.

Returns

Transmit address for DMA access.

static uint32_t spi_get_tx_on_rx_empty_setting ( Spi *  p_spi )

inlinestatic

Check if SPI waits RX_EMPTY before transfer starts.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 for SPI waits, 0 for no wait.

static uint32_t spi_is_enabled ( Spi *  p_spi )

inlinestatic

Test if the SPI is enabled.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 if the SPI is enabled, otherwise 0.

static uint32_t spi_is_rx_full ( Spi *  p_spi )

inlinestatic

Check if the SPI contains a received character.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 if the SPI Receive Holding Register is full, otherwise 0.

static uint32_t spi_is_rx_ready ( Spi *  p_spi )

inlinestatic

Check if all receptions are ready.

Parameters

p_spi

Pointer to an SPI instance.

Returns

1 if the SPI Receiver is ready, otherwise 0.

static uint32_t spi_is_tx_empty ( Spi *  p_spi )

inlinestatic

Check if all transmissions are complete.

Parameters

p_spi

Pointer to an SPI instance.

Return values

1	if transmissions are complete.
0	if transmissions are not complete.

static uint32_t spi_is_tx_ready ( Spi *  p_spi )

inlinestatic

Check if all transmissions are ready.

Parameters

p_spi

Pointer to an SPI instance.

Return values

1	if transmissions are complete.
0	if transmissions are not complete.

static void spi_put ( Spi *  p_spi, uint16_t  data  )

inlinestatic

Put one data to a SPI peripheral.

Parameters

p_spi	Base address of the SPI instance.
data	The data byte to be loaded

static uint32_t spi_read_interrupt_mask ( Spi *  p_spi )

inlinestatic

Read SPI interrupt mask.

Parameters

p_spi

Pointer to an SPI instance.

Returns

The interrupt mask value.

static uint32_t spi_read_status ( Spi *  p_spi )

inlinestatic

Read status register.

Parameters

p_spi

Pointer to an SPI instance.

Returns

SPI status register value.

static void spi_reset ( Spi *  p_spi )

inlinestatic

Reset SPI and set it to Slave mode.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize(), and spi_slave_initialize().

static void spi_set_fixed_peripheral_select ( Spi *  p_spi )

inlinestatic

Set Fixed Peripheral Select.

Peripheral Chip Select is controlled by SPI_MR.

Parameters

p_spi

Pointer to an SPI instance.

static void spi_set_lastxfer ( Spi *  p_spi )

inlinestatic

Issue a LASTXFER command.

The next transfer is the last transfer and after that CS is de-asserted.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize().

static void spi_set_master_mode ( Spi *  p_spi )

inlinestatic

Set SPI to Master mode.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_master_initialize().

static void spi_set_slave_mode ( Spi *  p_spi )

inlinestatic

Set SPI to Slave mode.

Parameters

p_spi

Pointer to an SPI instance.

Referenced by spi_slave_initialize().

static void spi_set_variable_peripheral_select ( Spi *  p_spi )

inlinestatic

Set Variable Peripheral Select.

Peripheral Chip Select can be controlled by SPI_TDR.

Parameters

p_spi

Pointer to an SPI instance.