twim.c File Reference

TWIM driver for SAM.

This file defines a useful set of functions for the TWIM on SAM4L devices.

Copyright (c) 2012-2018 Microchip Technology Inc. and its subsidiaries.

#include "twim.h"
#include "sleepmgr.h"
#include "sysclk.h"

Macros
#define	NCMDR_FREE_WAIT   2000
#define	TWIM_MAX_NBYTES_PER_XFER   (TWIM_CMDR_NBYTES_Msk >> TWIM_CMDR_NBYTES_Pos)

Functions
static uint32_t	find_twim_channel_num (Twim *twim)
	Get TWIM channel number. More...
status_code_t	twi_master_read (Twim *twim, struct twim_package *package)
	Read multiple bytes from a TWI compatible slave device. More...
status_code_t	twi_master_write (Twim *twim, struct twim_package *package)
	Write multiple bytes to a TWI compatible slave device. More...
void	twim_clear_status (Twim *twim, uint32_t clear_status)
	Clear the current status of the TWIM. More...
void	twim_default_callback (Twim *twim)
	TWIM default callback function. More...
void	twim_disable_interrupt (Twim *twim, uint32_t interrupt_source)
	Disable the TWIM interrupts and clear their status. More...
void	twim_enable_interrupt (Twim *twim, uint32_t interrupt_source)
	Enable the TWIM interrupts. More...
uint32_t	twim_get_interrupt_mask (Twim *twim)
	Get the TWIM interrupt mask. More...
uint32_t	twim_get_status (Twim *twim)
	Information about the current status of the TWIM. More...
void	twim_pdca_transfer_prepare (Twim *twim, twi_package_t *package, bool read)
	Set TWIM for PDCA transfer. More...
status_code_t	twim_probe (Twim *twim, uint32_t chip_addr)
	Test if a chip answers for a given TWI address. More...
void	twim_set_callback (Twim *twim, uint32_t interrupt_source, twim_callback_t callback, uint8_t irq_level)
	Set callback for TWIM. More...
status_code_t	twim_set_config (Twim *twim, struct twim_config *config)
	Initialize the TWIM module. More...
status_code_t	twim_set_hsmode_speed (Twim *twim, uint32_t speed, uint32_t clk, uint8_t cycles)
	Set the TWI bus speed in conjunction with the clock frequency in high speed mode. More...
status_code_t	twim_set_speed (Twim *twim, uint32_t speed, uint32_t clk, uint8_t cycles)
	Set the TWI bus speed in conjunction with the clock frequency. More...

Variables
static volatile uint8_t *	p_twim_next_rx_data [NUM_TWIM_CH] = {NULL}
static const volatile uint8_t *	p_twim_next_tx_data [NUM_TWIM_CH] = {NULL}
static volatile uint8_t *	p_twim_rx_data [NUM_TWIM_CH] = {NULL}
static const volatile uint8_t *	p_twim_tx_data [NUM_TWIM_CH] = {NULL}
static volatile twim_transfer_status_t	transfer_status [NUM_TWIM_CH]
twim_callback_t	twim_callback_pointer [NUM_TWIM_CH]
	TWIM callback function pointer array. More...
static volatile uint32_t	twim_it_mask [NUM_TWIM_CH]
static volatile bool	twim_next_cmd_xfer_valid [NUM_TWIM_CH] = {false}
static volatile uint32_t	twim_next_rx_nb_bytes [NUM_TWIM_CH] = {0}
static volatile uint32_t	twim_next_tx_nb_bytes [NUM_TWIM_CH] = {0}
static volatile uint32_t	twim_rx_nb_bytes [NUM_TWIM_CH] = {0}
static volatile uint32_t	twim_tx_nb_bytes [NUM_TWIM_CH] = {0}

#define NCMDR_FREE_WAIT   2000

Referenced by twim_default_callback().

#define TWIM_MAX_NBYTES_PER_XFER   (TWIM_CMDR_NBYTES_Msk >> TWIM_CMDR_NBYTES_Pos)

Max value of NBYTES per transfer by hardware

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

static uint32_t find_twim_channel_num ( Twim *  twim )

static

Get TWIM channel number.

Parameters

twim	Base address of the TWIM

Returns

TWIM channel number

Referenced by twi_master_read(), twi_master_write(), twim_default_callback(), and twim_set_callback().

volatile uint8_t* p_twim_next_rx_data[NUM_TWIM_CH] = {NULL}

static

Pointer to the application TWI receive buffer for next transfer.

Referenced by twi_master_read(), and twim_default_callback().

const volatile uint8_t* p_twim_next_tx_data[NUM_TWIM_CH] = {NULL}

static

Pointer to the application TWI transmit buffer for next transfer.

Referenced by twi_master_write(), and twim_default_callback().

volatile uint8_t* p_twim_rx_data[NUM_TWIM_CH] = {NULL}

static

Pointer to the application TWI receive buffer.

Referenced by twi_master_read(), and twim_default_callback().

const volatile uint8_t* p_twim_tx_data[NUM_TWIM_CH] = {NULL}

static

Pointer to the application TWI transmit buffer.

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

volatile twim_transfer_status_t transfer_status[NUM_TWIM_CH]

static

Status of the bus transfer

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

twim_callback_t twim_callback_pointer[NUM_TWIM_CH]

TWIM callback function pointer array.

Referenced by twim_set_callback().

volatile uint32_t twim_it_mask[NUM_TWIM_CH]

static

IT mask.

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

volatile bool twim_next_cmd_xfer_valid[NUM_TWIM_CH] = {false}

static

If next transfer command valid

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

volatile uint32_t twim_next_rx_nb_bytes[NUM_TWIM_CH] = {0}

static

Remaining number of bytes to receive for next transfer.

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

volatile uint32_t twim_next_tx_nb_bytes[NUM_TWIM_CH] = {0}

static

Remaining number of bytes to transmit for next transfer.

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().

volatile uint32_t twim_rx_nb_bytes[NUM_TWIM_CH] = {0}

static

Remaining number of bytes to receive per command.

Referenced by twi_master_read(), and twim_default_callback().

volatile uint32_t twim_tx_nb_bytes[NUM_TWIM_CH] = {0}

static

Remaining number of bytes to transmit per command.

Referenced by twi_master_read(), twi_master_write(), and twim_default_callback().