I2C Master (r_sau_i2c)

Functions
fsp_err_t	R_SAU_I2C_Open (i2c_master_ctrl_t *const p_api_ctrl, i2c_master_cfg_t const *const p_cfg)
fsp_err_t	R_SAU_I2C_Read (i2c_master_ctrl_t *const p_api_ctrl, uint8_t *const p_dest, uint32_t const bytes, bool const restart)
fsp_err_t	R_SAU_I2C_Write (i2c_master_ctrl_t *const p_api_ctrl, uint8_t *const p_src, uint32_t const bytes, bool const restart)
fsp_err_t	R_SAU_I2C_Abort (i2c_master_ctrl_t *const p_api_ctrl)
fsp_err_t	R_SAU_I2C_SlaveAddressSet (i2c_master_ctrl_t *const p_api_ctrl, uint32_t const slave, i2c_master_addr_mode_t const addr_mode)
fsp_err_t	R_SAU_I2C_CallbackSet (i2c_master_ctrl_t *const p_api_ctrl, void(*p_callback)(i2c_master_callback_args_t *), void const *const p_context, i2c_master_callback_args_t *const p_callback_memory)
fsp_err_t	R_SAU_I2C_StatusGet (i2c_master_ctrl_t *const p_api_ctrl, i2c_master_status_t *p_status)
fsp_err_t	R_SAU_I2C_Close (i2c_master_ctrl_t *const p_api_ctrl)
fsp_err_t	R_SAU_I2C_Start (sau_i2c_instance_ctrl_t *const p_ctrl)
fsp_err_t	R_SAU_I2C_Stop (sau_i2c_instance_ctrl_t *const p_ctrl)

Detailed Description

Driver for the SAU peripheral on RA MCUs. This module implements the I2C Master Interface.

Overview

The Simple I2C master on SAU HAL module supports transactions with an I2C Slave device. Callbacks must be provided which would be invoked when a transmission or receive has been completed. The callback arguments will contain information about the transaction status, bytes transferred and a pointer to the user defined context.

Features

• Supports multiple transmission rates
  • Standard Mode Support with up to 100 kHz transaction rate.
  • Fast Mode Support with up to 400 kHz transaction rate.
  • Fast Mode Plus Support with up to 1-MHz transaction rate.
• I2C Master Read from a slave device.
• I2C Master Write to a slave device.
• Set the address of the slave device.
• Non-blocking behavior is achieved by the use of callbacks.
• Additional build-time features
  • Optional (build time) DTC support for read and write respectively.

Configuration

Build Time Configurations for r_sau_i2c

The following build time configurations are defined in fsp_cfg/r_sau_i2c_cfg.h:

Configuration	Options	Default	Description
Parameter Checking	Default (BSP) Enabled Disabled	Default (BSP)	If selected code for parameter checking is included in the build.
Enable Critical Section	Enabled Disabled	Disabled	Critical section needs to be enabled if multiple channels on the same SAU unit are configured for I2C
Manual Start-Stop	Enabled Disabled	Disabled	If enabled, users need to manually call the R_SAU_I2C_Start/R_SAU_I2C_Stop functions to generate the I2C start and stop conditions.
Enable Single Channel	MCU Specific Options		Enable single channel to reduce code size if only one channel is to be configured for SAU I2C.
I2C Restart	Enable Disable	Enable	Select whether to include code for the I2C restart (repeated start) condition in the build. Set to 'Disable' to reduce code size when all I2C slaves used by all SAU instances do not use I2C restart.
DTC Support	Enable Disable	Disable	Enable DTC support for the SAU I2C module.

Configurations for Connectivity > I2C Master (r_sau_i2c)

This module can be added to the Stacks tab via New Stack > Connectivity > I2C Master (r_sau_i2c).

Configuration	Options	Default	Description
General
Name	Name must be a valid C symbol	g_i2c0	Module name.
Channel	MCU Specific Options		Select the SAU channel.
Operation clock	CK0 CK1	CK0	Select the I2C operation clock. Use the Clocks tab to set the operation clock divider.
Slave Address	Value must be a non-negative integer	0x00	Specify the slave address.
Rate	Standard Fast mode Fast mode plus	Standard	Select the I2C data rate. If the requested rate cannot be achieved, adjust the operation clock frequency until the rate is achievable. The calculated rate is printed in a comment in the generated sau_i2c_extended_cfg_t structure.
Delay time (Microseconds)	Value must be a non-negative integer	5	Hold SDA (or SCK) for delay time to meet the I2C start (or stop) condition. Needs to be specified according to slave devices.
Callback	Name must be a valid C symbol	sau_i2c_master_callback	A user callback function can be provided. If this callback function is provided, it will be called from the interrupt service routine (ISR).
Transfer end interrupt priority	MCU Specific Options		Select transfer end interrupt priority. This is set for TEI interrupt.
Custom Rate (bps)	Value must be a non-negative integer	0	Set a custom bitrate (bps). Set to 0 to use the maximum bitrate for the selected mode. Standard-mode: up to 100000; Fast-mode: up to 400000; Fast-mode plus: up to 1000000

Clock Configuration

The SAU clock uses the system clock (ICLK) as its clock source.

A prescaler is applied to the ICLK in order to produce the operation clock frequency. The operation clock is used to generate the desired transfer period of the SAU module.

SAU operation clocks are shared among all channels within a SAU unit. Check the Hardware User's Manual for your MCU for available units and channels. SAU operation clock dividers are configurable in the Clocks tab.

The operation clock dividers are named SAU CKmn where m is the SAU unit, and n is the operation clock. For example, SAU CK01 applies to all SAU0 instances using CK1 as the operation clock (m=0, n=1).

Pin Configuration

The SAU I2C peripheral module uses pins on the MCU to communicate to external devices. I/O pins must be selected and configured as required by the external device. An I2C channel would consist of two pins - SDA and SCL for data/address and clock respectively.

Usage Notes

Enabling Single Channel By User With The SAU I2C

• The Common > Single Channel property is used for reducing code size when only 1 SAU channel is to be configured for SAU I2C.
• Single Channel is configurable and disabled by default in the driver code.
• Note: Not all SAU channels are available on all pin layouts. Check the Hardware User Manual for your device to confirm available function assignment for each SAU channel.

Enabling Start/Stop Condition By User With The SAU I2C

• Manual triggering of I2C start/stop conditions is configurable and disabled by default.
• The delay time between the rising edge of SCL and the rising edge of SDA (stop condition) or the falling edge of SDA and the falling edge of SCL (start condition) is blocking. If blocking in the ISR for the length of the delay time is not suitable for the application, users can decide the appropriate calling time for start/stop conditions by enabling manual triggering and calling R_SAU_I2C_Start/R_SAU_I2C_Stop from the application context.
• When manual triggering is disabled, the driver will generate the stop condition after data transmission from the ISR context.

Interrupt Configuration

• Transmit end interrupt (TEI) for the selected channel used must be enabled in the properties of the selected device.

SAU I2C Master Rate Calculation

• The RA Configuration editor calculates the internal baud-rate setting based on the configured transfer rate and operating clock.

  When the Custom Rate setting is set to 0 the bitrate is fixed to the maximum values shown below. Otherwise, the supplied value is used to generate bitrate settings.

  • Standard-mode (Sm) : up to 100 kbps
  • Fast-mode (Fm) : up to 400 kbps
  • Fast-mode Plus (Fm+) : up to 1 Mbps
• The closest possible baud-rate that can be achieved (less than or equal to the requested rate) at the current PCLK settings is calculated and used.
• If a valid clock rate could not be calculated, an error is returned by the tool.

Selecting Operation Clock Frequency

The relationship between operation clock frequency and bitrate is: bitrate = f_mck / [ 2 * (SDRmn.STCLK + 1) ] where:

• SDRmn.STCLK is an integer in the range [1, 127] for SAU I2C
• f_mck is the operation clock (SAU CKmn) frequency

By plugging in the minimum and maximum SDRmn.STCLK values, the range of bitrates for a given operation clock frequency can be obtained.

Note that due to STCLK being set as discrete integers, the actual bitrate may not be exact. The actual bitrate and percent errors can be calculated by the formulas:

actual_bitrate = f_mck / [ 2 * (SDRmn.STCLK + 1) ]
percent_error = 100 * abs [(actual_bitrate - expected_bitrate)  / expected_bitrate]

Using the fastest possible operation clock for the desired bitrate will result in the lowest deviation from the requested bitrate. Set the CKmn operation clock divider in the Clocks tab to select the desired operation clock frequency.

Enabling DTC with the SAU I2C

• DTC transfer support is configurable and is disabled from the build by default. The SAU I2C driver uses a single DTC instance for transmission and reception.
• DTC is helpful for minimizing interrupts during large transactions. Many I2C applications have shorter transactions. These applications will likely not see any improvement with DTC. I2C often runs at a much slower speed than the CPU core clock. Some applications with longer transactions may prefer servicing the interrupts at the I2C bitrate to the overhead of bringing in the DTC driver.
• If DTC is not used by any SAU instance, set Common > DTC Support to disabled to reduce code size.
• For further details on DTC please refer Transfer (r_dtc)

Multiple Channels Being Used In Same Unit

• When multiple channels on the same SAU unit are used for any serial function (I2C, UART, and/or SPI), then the Common > Enable Critical Section property needs to be set to enabled for all SAU serial drivers.
  • This is because some SAU registers are shared for SAU channels on the same unit. Therefore any read-modify-write operations to those registers must be protected by a critical section.

I2C Restart Support

• I2C Restart (repeated start) is required by some, but not all slave devices.
• If no slave devices used by any SAU I2C instance require repeated start, then the Common > I2C Restart property can be set to disabled to reduce code size.
• When I2C Restart is disabled, even if restart=true is passed to the read or write APIs, the restart condition is not issued.

Multiple Devices On The Bus

• A single SAU I2C instance can be used to communicate with multiple slave devices on the same channel by using the R_SAU_I2C_SlaveAddressSet API.

Limitations

• Overrun error detection is not supported
• SAU I2C does not support clock stretching, I2C slave mode, or arbitration loss detection

Examples

Basic Example

This is a basic example of minimal use of the r_sau_i2c in an application. This example shows how this driver can be used for basic read and write operations.

void basic_example (void)
{
    fsp_err_t err;
    uint32_t  i;
    uint32_t  timeout_ms = I2C_TRANSACTION_BUSY_DELAY;


    /* Initialize the I2C module */
    err = R_SAU_I2C_Open(&g_i2c_device_ctrl_1, &g_i2c_device_cfg_1);


    /* Handle any errors. This function should be defined by the user. */
    assert(FSP_SUCCESS == err);

    /* Write some data to the transmit buffer */
    for (i = 0; i < I2C_BUFFER_SIZE_BYTES; i++)
    {
        g_i2c_tx_buffer[i] = (uint8_t) i;
    }

    /* Send data to I2C slave */
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;


    err = R_SAU_I2C_Write(&g_i2c_device_ctrl_1, &g_i2c_tx_buffer[0], I2C_BUFFER_SIZE_BYTES, false);
    assert(FSP_SUCCESS == err);


    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_TX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }

    /* Read data back from the I2C slave */
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    timeout_ms           = I2C_TRANSACTION_BUSY_DELAY;


    err = R_SAU_I2C_Read(&g_i2c_device_ctrl_1, &g_i2c_rx_buffer[0], I2C_BUFFER_SIZE_BYTES, false);
    assert(FSP_SUCCESS == err);


    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_RX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }

    /* Verify the read data */
    if (0U != memcmp(g_i2c_tx_buffer, g_i2c_rx_buffer, I2C_BUFFER_SIZE_BYTES))
    {
        __BKPT(0);
    }
}

Enabling Start/Stop Condition By User

This example demonstrates how to write code for SAU I2C communication when the call start/stop condtion by user is enabled.

void manual_trigger_condition_example (void)
{
    fsp_err_t err;
    uint32_t  i;
    uint32_t  timeout_ms = I2C_TRANSACTION_BUSY_DELAY;


    /* Initialize the I2C module */
    err = R_SAU_I2C_Open(&g_i2c_device_ctrl_1, &g_i2c_device_cfg_1);


    /* Handle any errors. This function should be defined by the user. */
    assert(FSP_SUCCESS == err);

    /* Write some data to the transmit buffer */
    for (i = 0; i < I2C_BUFFER_SIZE_BYTES; i++)
    {
        g_i2c_tx_buffer[i] = (uint8_t) i;
    }

    /* Send data to I2C slave */
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;


    err = R_SAU_I2C_Write(&g_i2c_device_ctrl_1, &g_i2c_tx_buffer[0], I2C_BUFFER_SIZE_BYTES, false);
    assert(FSP_SUCCESS == err);



    err = R_SAU_I2C_Start(&g_i2c_device_ctrl_1);
    assert(FSP_SUCCESS == err);


    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_TX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }

    err = R_SAU_I2C_Stop(&g_i2c_device_ctrl_1);
    assert(FSP_SUCCESS == err);

    /* Read data back from the I2C slave */
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    timeout_ms           = I2C_TRANSACTION_BUSY_DELAY;


    err = R_SAU_I2C_Read(&g_i2c_device_ctrl_1, &g_i2c_rx_buffer[0], I2C_BUFFER_SIZE_BYTES, false);
    assert(FSP_SUCCESS == err);



    err = R_SAU_I2C_Start(&g_i2c_device_ctrl_1);
    assert(FSP_SUCCESS == err);


    /* Since there is nothing else to do, block until Callback triggers*/
    while ((I2C_MASTER_EVENT_RX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    err = R_SAU_I2C_Stop(&g_i2c_device_ctrl_1);
    assert(FSP_SUCCESS == err);

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }

    /* Verify the read data */
    if (0U != memcmp(g_i2c_tx_buffer, g_i2c_rx_buffer, I2C_BUFFER_SIZE_BYTES))
    {
        __BKPT(0);
    }
}

Multiple Slave Devices On The Same Channel (Bus)

This example demonstrates how a single SAU I2C driver can be used to communicate with different slave devices which are on the same channel.

void single_channel_multi_slave (void)
{
    fsp_err_t err;
    uint32_t  timeout_ms = I2C_TRANSACTION_BUSY_DELAY;

    err = R_SAU_I2C_Open(&g_i2c_device_ctrl_2, &g_i2c_device_cfg_2);

    /* Handle any errors. This function should be defined by the user. */
    assert(FSP_SUCCESS == err);

    /* Clear the recieve buffer */
    memset(g_i2c_rx_buffer, '0', I2C_BUFFER_SIZE_BYTES);

    /* Read data from I2C slave */
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    err = R_SAU_I2C_Read(&g_i2c_device_ctrl_2, &g_i2c_rx_buffer[0], I2C_BUFFER_SIZE_BYTES, false);
    assert(FSP_SUCCESS == err);

    while ((I2C_MASTER_EVENT_RX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }

    /* Send data to I2C slave on the same channel */
    err = R_SAU_I2C_SlaveAddressSet(&g_i2c_device_ctrl_2, I2C_SLAVE_DISPLAY_ADAPTER, I2C_MASTER_ADDR_MODE_7BIT);
    assert(FSP_SUCCESS == err);

    g_i2c_tx_buffer[0]   = (uint8_t) I2C_EXAMPLE_DATA_1;
    g_i2c_tx_buffer[1]   = (uint8_t) I2C_EXAMPLE_DATA_2;
    g_i2c_callback_event = I2C_MASTER_EVENT_ABORTED;
    timeout_ms           = I2C_TRANSACTION_BUSY_DELAY;
    err = R_SAU_I2C_Write(&g_i2c_device_ctrl_2, &g_i2c_tx_buffer[0], 2U, false);
    assert(FSP_SUCCESS == err);

    while ((I2C_MASTER_EVENT_TX_COMPLETE != g_i2c_callback_event) && timeout_ms)
    {
        R_BSP_SoftwareDelay(1U, BSP_DELAY_UNITS_MILLISECONDS);
        timeout_ms--;;
    }

    if (I2C_MASTER_EVENT_ABORTED == g_i2c_callback_event)
    {
        __BKPT(0);
    }
}

Data Structures
struct	sau_i2c_clock_settings_t
struct	sau_i2c_instance_ctrl_t
struct	sau_i2c_extended_cfg_t

Enumerations
enum	sau_i2c_operation_clock_t

---

Data Structure Documentation

sau_i2c_clock_settings_t

struct sau_i2c_clock_settings_t

I2C clock settings

Data Fields
uint8_t	stclk	Bit rate register settings.
sau_i2c_operation_clock_t	operation_clock	I2C operating clock select.

sau_i2c_instance_ctrl_t

struct sau_i2c_instance_ctrl_t

I2C control structure. DO NOT INITIALIZE.

Data Fields
i2c_master_cfg_t const *	p_cfg
	Pointer to the configuration structure.
uint32_t	open
	Flag to determine if the device is open.
R_SAU0_Type *	p_reg
	Base register for this channel.
uint8_t *	p_buff
	Holds the data associated with the transfer.
uint32_t	total
	Holds the total number of data bytes to transfer.
uint32_t	loaded
	Tracks the number of data bytes written to the register.
volatile bool	read
	Holds the direction of the data byte transfer.
volatile bool	restart
	Holds whether or not the restart should be issued when done.
volatile bool	restarted
	Tracks whether or not a restart was issued during the previous transfer.
volatile bool	do_dummy_read
	Tracks whether a dummy read is issued on the first RX.
uint8_t	slave
	The address of the slave device.

sau_i2c_extended_cfg_t

struct sau_i2c_extended_cfg_t

SAU I2C extended configuration

Data Fields
sau_i2c_clock_settings_t	clock_settings	I2C clock settings.
uint8_t	delay_time	The delay time of the slave device.
uint8_t	i2c_unit	The SAU unit corresponding to the selected channel.

Enumeration Type Documentation

sau_i2c_operation_clock_t

enum sau_i2c_operation_clock_t

Operation clock

Enumerator
SAU_I2C_MASTER_OPERATION_CLOCK_CK0	Operating clock select CK0.
SAU_I2C_MASTER_OPERATION_CLOCK_CK1	Operating clock select CK1.

Function Documentation

R_SAU_I2C_Open()

fsp_err_t R_SAU_I2C_Open	(	i2c_master_ctrl_t *const	p_api_ctrl,
		i2c_master_cfg_t const *const	p_cfg
	)

Opens the SAU device.

Return values

FSP_SUCCESS	Requested clock rate was set exactly.
FSP_ERR_ALREADY_OPEN	Module is already open.
FSP_ERR_ASSERTION	Parameter check failure due to one or more reasons below: p_api_ctrl or p_cfg is NULL. extended parameter is NULL. Callback parameter is NULL. Clock rate requested is greater than 400KHz Invalid IRQ number assigned

R_SAU_I2C_Read()

fsp_err_t R_SAU_I2C_Read	(	i2c_master_ctrl_t *const	p_api_ctrl,
		uint8_t *const	p_dest,
		uint32_t const	bytes,
		bool const	restart
	)

Performs a read from the I2C device. The caller will be notified when the operation has completed (successfully) by an I2C_MASTER_EVENT_RX_COMPLETE in the callback.

Return values

FSP_SUCCESS	Function executed without issue.
FSP_ERR_ASSERTION	The parameter p_api_ctrl, p_dest is NULL, bytes is 0.
FSP_ERR_INVALID_SIZE	Provided number of bytes more than uint16_t size (65535) while DTC is used for data transfer.
FSP_ERR_NOT_OPEN	Instance control block is not open.

R_SAU_I2C_Write()

fsp_err_t R_SAU_I2C_Write	(	i2c_master_ctrl_t *const	p_api_ctrl,
		uint8_t *const	p_src,
		uint32_t const	bytes,
		bool const	restart
	)

Performs a write to the I2C device.

This function will fail if there is already an in-progress I2C transfer on the associated channel. Otherwise, the I2C write operation will begin. The write operation is non-blocking and the caller will be notified when the operation has finished by an I2C_EVENT_TX_COMPLETE in the callback.

Return values

FSP_SUCCESS	Function executed without issue.
FSP_ERR_ASSERTION	p_api_ctrl, p_src is NULL.
FSP_ERR_INVALID_SIZE	Provided number of bytes more than uint16_t size (65535) while DTC is used for data transfer.
FSP_ERR_NOT_OPEN	Instance control block is not open.

R_SAU_I2C_Abort()

fsp_err_t R_SAU_I2C_Abort

(

i2c_master_ctrl_t *const

p_api_ctrl

)

Aborts any in-progress transfer and forces the I2C peripheral into a ready state.

This function will safely terminate any in-progress I2C transfer with the device. If a transfer is aborted, the user will be notified via callback with an abort event.

Return values

FSP_SUCCESS	Transaction was aborted without issue.
FSP_ERR_ASSERTION	p_ctrl is NULL.
FSP_ERR_NOT_OPEN	Instance control block is not open.

R_SAU_I2C_SlaveAddressSet()

fsp_err_t R_SAU_I2C_SlaveAddressSet	(	i2c_master_ctrl_t *const	p_api_ctrl,
		uint32_t const	slave,
		i2c_master_addr_mode_t const	addr_mode
	)

Sets address of the slave device.

This function is used to set the device address of the slave without reconfiguring the entire bus.

Return values

FSP_SUCCESS	Address of the slave is set correctly.
FSP_ERR_ASSERTION	p_ctrl or address is NULL.
FSP_ERR_NOT_OPEN	Instance control block is not open.
FSP_ERR_IN_USE	An I2C Transaction is in progress.

R_SAU_I2C_CallbackSet()

fsp_err_t R_SAU_I2C_CallbackSet	(	i2c_master_ctrl_t *const	p_api_ctrl,
		void(*)(i2c_master_callback_args_t *)	p_callback,
		void const *const	p_context,
		i2c_master_callback_args_t *const	p_callback_memory
	)

Updates the user callback.

Note

p_callback_memory is not used in this implementation and can be set to NULL.

Implements i2c_master_api_t::callbackSet

Return values

FSP_SUCCESS	Callback updated successfully.
FSP_ERR_ASSERTION	A required pointer is NULL.
FSP_ERR_NOT_OPEN	The control block has not been opened.

R_SAU_I2C_StatusGet()

fsp_err_t R_SAU_I2C_StatusGet	(	i2c_master_ctrl_t *const	p_api_ctrl,
		i2c_master_status_t *	p_status
	)

Provides driver status.

Return values

FSP_SUCCESS	Status stored in p_status.
FSP_ERR_ASSERTION	NULL pointer.

R_SAU_I2C_Close()

fsp_err_t R_SAU_I2C_Close

(

i2c_master_ctrl_t *const

p_api_ctrl

)

Closes the I2C device. Power down I2C peripheral.

This function will safely terminate any in-progress I2C transfer with the device. If a transfer is aborted, the user will be notified via callback with an abort event.

Return values

FSP_SUCCESS	Device closed without issue.
FSP_ERR_ASSERTION	The parameter p_ctrl is NULL.
FSP_ERR_NOT_OPEN	Instance control block is not open.

R_SAU_I2C_Start()

fsp_err_t R_SAU_I2C_Start

(

sau_i2c_instance_ctrl_t *const

p_ctrl

)

This function starts/restarts the IIC condition.

Parameters

[in]

p_ctrl

Instance control structure.

R_SAU_I2C_Stop()

fsp_err_t R_SAU_I2C_Stop

(

sau_i2c_instance_ctrl_t *const

p_ctrl

)

This function stops the IIC condition.

Parameters

[in]

p_ctrl

Instance control structure.