neorv32_spi.c File Reference

Serial peripheral interface controller (SPI) HW driver source file. More...

#include <neorv32.h>

Functions
int	neorv32_spi_available (void)
void	neorv32_spi_setup (int prsc, int cdiv, int clk_phase, int clk_polarity, uint32_t irq_mask)
void	neorv32_spi_highspeed_enable (void)
void	neorv32_spi_highspeed_disable (void)
uint32_t	neorv32_spi_get_clock_speed (void)
void	neorv32_spi_disable (void)
void	neorv32_spi_enable (void)
int	neorv32_spi_get_fifo_depth (void)
void	neorv32_spi_cs_en (int cs)
void	neorv32_spi_cs_dis (void)
uint8_t	neorv32_spi_trans (uint8_t tx_data)
void	neorv32_spi_put_nonblocking (uint8_t tx_data)
uint8_t	neorv32_spi_get_nonblocking (void)
void	neorv32_spi_cs_en_nonblocking (int cs)
void	neorv32_spi_cs_dis_nonblocking (void)
int	neorv32_spi_check_cs (void)
int	neorv32_spi_busy (void)

Detailed Description

Serial peripheral interface controller (SPI) HW driver source file.

Note

These functions should only be used if the SPI unit was synthesized (IO_SPI_EN = true).

See also

https://stnolting.github.io/neorv32/sw/files.html

Function Documentation

neorv32_spi_available()

int neorv32_spi_available

(

void

)

Check if SPI unit was synthesized.

Returns

0 if SPI was not synthesized, 1 if SPI is available.

neorv32_spi_busy()

int neorv32_spi_busy

(

void

)

Check if SPI transceiver is busy or TX FIFO not empty.

Returns

0 if idle, 1 if busy

neorv32_spi_check_cs()

int neorv32_spi_check_cs

(

void

)

Check if any chip-select line is active.

Returns

0 if no CS lines are active, 1 if at least one CS line is active.

neorv32_spi_cs_dis()

void neorv32_spi_cs_dis

(

void

)

Deactivate currently active SPI chip select signal.

Note

The SPI chip select output lines are HIGH when deactivated.

This function is blocking.

neorv32_spi_cs_dis_nonblocking()

void neorv32_spi_cs_dis_nonblocking

(

void

)

Deactivate currently active SPI chip select signal (non-blocking).

Note

The SPI chip select output lines are HIGH when deactivated.

neorv32_spi_cs_en()

void neorv32_spi_cs_en

(

int

cs

)

Activate single SPI chip select signal.

Note

The SPI chip select output lines are LOW when activated.

This function is blocking.

Parameters

cs	Chip select line to activate (0..7).

neorv32_spi_cs_en_nonblocking()

void neorv32_spi_cs_en_nonblocking

(

int

cs

)

Activate single SPI chip select signal (non-blocking).

Note

The SPI chip select output lines are LOW when activated.

Parameters

cs	Chip select line to activate (0..7).

neorv32_spi_disable()

void neorv32_spi_disable

(

void

)

Disable SPI controller.

neorv32_spi_enable()

void neorv32_spi_enable

(

void

)

Enable SPI controller.

neorv32_spi_get_clock_speed()

uint32_t neorv32_spi_get_clock_speed

(

void

)

Get configured clock speed in Hz.

Returns

Actual configured SPI clock speed in Hz.

neorv32_spi_get_fifo_depth()

int neorv32_spi_get_fifo_depth

(

void

)

Get SPI FIFO depth.

Returns

FIFO depth (number of entries), zero if no FIFO implemented

neorv32_spi_get_nonblocking()

uint8_t neorv32_spi_get_nonblocking

(

void

)

Get SPI RX data (non-blocking).

Returns

Receive data (8-bit, LSB-aligned).

neorv32_spi_highspeed_disable()

void neorv32_spi_highspeed_disable

(

void

)

Disable high-speed mode.

neorv32_spi_highspeed_enable()

void neorv32_spi_highspeed_enable

(

void

)

Enable high-speed mode.

neorv32_spi_put_nonblocking()

void neorv32_spi_put_nonblocking

(

uint8_t

tx_data

)

Put SPI TX data (non-blocking).

Parameters

tx_data

Transmit data (8-bit, LSB-aligned).

neorv32_spi_setup()

void neorv32_spi_setup	(	int	prsc,
		int	cdiv,
		int	clk_phase,
		int	clk_polarity,
		uint32_t	irq_mask )

Enable and configure SPI controller. The SPI control register bits are listed in NEORV32_SPI_CTRL_enum.

Parameters

[in]	prsc	Clock prescaler select (0..7). See NEORV32_CLOCK_PRSC_enum. @prama[in] cdiv Clock divider (0..15).
[in]	clk_phase	Clock phase (0=sample on rising edge, 1=sample on falling edge).
[in]	clk_polarity	Clock polarity (when idle).
[in]	irq_mask	Interrupt configuration mask (CTRL's irq_* bits).

neorv32_spi_trans()

uint8_t neorv32_spi_trans

(

uint8_t

tx_data

)

Perform a single SPI data transfer.

Note

This function is blocking.

Parameters

tx_data

Transmit data (8-bit, LSB-aligned).

Returns

Receive data (8-bit, LSB-aligned).