I2C_MASTER

Overview

Terms and acronyms

Terms	Details
DMA	Direct Memory Access. For an introduction to DMA, please refer to DMA in Wikipedia.
GPIO	General Purpose Inputs-Outputs. For more details, please refer to the GPIO module in HAL.
I2C	Inter-Integrated Circuit. I2C is typically used to attach low-speed peripheral ICs to processors and microcontrollers. For an introduction to I2C, please refer to I2C in Wikipedia.
NVIC	Nested Vectored Interrupt Controller. NVIC is the interrupt controller of ARM Cortex-M4. For more details, please refer to NVIC introduction in ARM Cortex-M4 Processor Technical Reference Manual.

Supported features

• Supported transaction modes

  • Polling mode transaction In polling mode, the functions with the suffix "_polling" will not return any value until the transaction is complete. After the function returns, the return value should be checked and the error status should be handled.
  • DMA mode transaction In DMA mode, the functions with the suffix "_dma" return a value once the I2C and DMA hardware registers are assigned. These functions do not wait for the transaction to finish. After the transaction finishes, an interrupt is triggered and the user callback in the I2C ISR routine is called. After the function returns, the return value should be checked and the error status should be handled.

  Note:
  

  1. For more infomation about the transaction length and waveform pattern for each API, please refer to Transaction Length And transaction packet of APIs.
     
  2. It is required to use the pull-up resistors on the SCL and SDA of the I2C interface. Please refer to related HDK user guide for more details.

Software architecture of the I2C

• Polling mode architecture.
  Polling mode architecture is similar to the polling mode architecture in HAL overview. See HAL Driver Model for polling mode architecture.
• DMA mode architecture.
  DMA mode architecture is similar to the interrupt mode architecture in HAL overview. See HAL Driver Model for interrupt mode architecture.

How to use this driver

• Using I2C in polling mode.
  To use I2C driver in a polling mode, configure GPIO pins to pinmux to SCL and SDA, then call hal_pinmux_set_function() to select the pinmux function. After setting the pinmux, call hal_i2c_master_get_running_status() to check the I2C status. If the status is HAL_I2C_STATUS_BUS_BUSY, wait till the status becomes HAL_I2C_STATUS_IDLE. Once the data is successfully transmitted, call hal_i2c_master_deinit() to release the I2C resource for other users.
  Steps are shown below:
  • Step1: Call hal_gpio_init() to initialize the pin. For mode details about hal_gpio_init please refer to GPIO module in HAL.
  • Step2: Call hal_pinmux_set_function() to set the GPIO pinmux or use the EPT tool to apply the pinmux settings.
  • Step3: Call hal_i2c_master_init() to initialize the I2C master.
  • Step4: Call hal_i2c_master_send_polling() to send data in a polling mode.
  • Step5: Call hal_i2c_master_receive_polling() to receive data in a polling mode.
  • Step6: Call hal_i2c_master_deinit() to de-allocate the I2C master if it is no longer in use.
  • Sample code:

    hal_i2c_config_t i2c_config;
    uint8_t slave_address = 0X50;
    const uint8_t send_data[8] = {0x00, 0x00, 0xFF, 0xAA, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}; //the data that used to send
    uint8_t receive_data[8] = {0};
    volatile uint32_t size = 8;
    i2c_config.frequency = HAL_I2C_FREQUENCY_400K;
    
    hal_gpio_init(gpio_pin); //init the gpio pin
    hal_pinmux_set_function(gpio_pin, function_index);//Set the pinmux
    if(HAL_I2C_STATUS_OK == hal_i2c_master_init(HAL_I2C_MASTER_0, &i2c_config)) {
        //Send data
        if (HAL_I2C_STATUS_OK != hal_i2c_master_send_polling(HAL_I2C_MASTER_0, slave_address, send_data, size)) {
            //Error handler;
        }
        //Receive data
        if (HAL_I2C_STATUS_OK != hal_i2c_master_receive_polling(HAL_I2C_MASTER_0, slave_address, receive_data, size)) {
            //Error handler;
        }
        hal_i2c_master_deinit(HAL_I2C_MASTER_0); //Call this function if the I2C is no longer in use.
    
    } else {
        //Error handler;
    }

• Using I2C in DMA mode.
  To use I2C driver in DMA mode, configure GPIO pins to pinmux to SCL and SDA, then call hal_pinmux_set_function to select the pinmux function. After setting the pinmux, call hal_i2c_master_get_running_status() to check the I2C status. If the status is HAL_I2C_STATUS_BUS_BUSY, user should wait till the status is HAL_I2C_STATUS_IDLE, then call hal_i2c_master_register_callback() to register a callback function. Once the data transaction is complete, call hal_i2c_master_deinit() in your callback function registered by hal_i2c_master_register_callback() to release the I2C resource to other users. Steps are shown below:
  • Step1: Call hal_gpio_init() to initialize the pin. For mode details about hal_gpio_init please refer to GPIO module in HAL.
  • Step2: Call hal_pinmux_set_function() to set the GPIO pinmux or use the EPT tool to apply the pinmux settings.
  • Step3: Call hal_i2c_master_init() to initialize the I2C master.
  • Step4: Call hal_i2c_master_register_callback() to register a user callback.
  • Step5: Call hal_i2c_master_send_dma() to send data within a DMA mode.
  • Step6: Call hal_i2c_master_receive_dma() to receive data in a DMA mode.
  • Step7: Call hal_i2c_master_deinit() to de-initialize the I2C master if it is no longer in use.
  • Sample code:

    hal_i2c_config_t i2c_config;
    uint8_t slave_address = 0X50;
    const uint8_t send_data[8] = {0x00, 0x00, 0xFF, 0xAA, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}; //the data that used to send
    uint8_t receive_data[8] = {0};
    volatile uint32_t size = 8;
    i2c_config.frequency = HAL_I2C_FREQUENCY_400K;
    
    hal_gpio_init(gpio_pin); //init the gpio pin
    hal_pinmux_set_function(gpio_pin, function_index);//Set the pinmux
    if(HAL_I2C_STATUS_OK == hal_i2c_master_init(HAL_I2C_MASTER_0, &i2c_config)) {
        hal_i2c_master_register_callback(HAL_I2C_MASTER_0, i2c_user_callback, (void *) &user_data)//Register a user callback.
        //Send data
        if (HAL_I2C_STATUS_OK != hal_i2c_master_send_dma(HAL_I2C_MASTER_0, slave_address, send_data, size)) {
            //Error handler;
        }
        //Receive data
        if (HAL_I2C_STATUS_OK != hal_i2c_master_receive_dma(HAL_I2C_MASTER_0, slave_address, receive_data, size)) {
            //Error handler;
        }
    } else {
        //Error handler;
    }
    //hal_i2c_master_deinit(i2c_port);// Call this function if the I2C is no longer in use.

    // Callback function sample code. This function should be passed to driver while calling the function #hal_i2c_master_register_callback().
    void i2c_user_callback (uint8_t slave_address,hal_i2c_callback_event_t event,void *user_data)
    {
        if(HAL_I2C_EVENT_ACK_ERROR == event) {
            //ACK error handler;
        } else if(HAL_I2C_EVENT_NACK_ERROR == event) {
            //NACK error handler;
        } else if(HAL_I2C_EVENT_TIMEOUT_ERROR == event) {
            // Timeout handler;
        } else if(HAL_I2C_EVENT_SUCCESS == event) {
            // Do something;
            // The slave_address indicates which device is using I2C.
        }
    }

Transaction Length And transaction packet of APIs

The Transaction packet is the transaction packet sent by the I2C master using SCL and SDA. Different APIs have different transaction packets, as shown below.

• Transaction length supported by the APIs
  The total transaction length is determined by 4 parameters:
  send_packet_length(Ns), which indicates the counts of send packet.
  send_bytes_in_one_packet(Ms).
  receive_packet_length(Nr).
  receive_bytes_in_one_packet(Mr).
  And also, these 4 parameters will affect the transaction packet. The ralationship between transaction packet and these 4 parameters will be introduced in the next section.
  • Total transaction length = Ns * Ms + Nr * Mr.
    • Ns is the packet length to be sent by the I2C master.
    • Ms is the total number of bytes in a sent packet.
    • Nr is the packet length to be received by the I2C master.
    • Mr is the total number of bytes in a received packet.
  • NA means the related parameter should be ignored.
  • 1~8 specifies the parameter range is from 1 to 8. 1~15 specifies the parameter range is from 1 to 15. 1~255 specifies the parameter range from 1 to 255.
  • 1 means the parameter value can only be 1.
  • Note: Only those functions with the suffix "_ex" have these 4 parameters. Other functions only have the "size" parameter and the driver splits the "size" into these 4 parameters. hal_i2c_master_send_polling() for example, the "size" will be divided like this: send_packet_length = 1, send_bytes_in_one_packet = size. As a result, the total size should be: send_packet_length * send_bytes_in_one_packet = 1 * size = size. The range of "size" should be from 1 to 8.

    API	send_packet_length(Ns)	send_bytes_in_one_packet(Ms)	receive_packet_length(Nr)	receive_bytes_in_one_packet(Mr)
    hal_i2c_master_send_polling	1	1~8	NA	NA
    hal_i2c_master_receive_polling	NA	NA	1	1~8
    hal_i2c_master_send_to_receive_polling	1	1~8	1	1~8
    hal_i2c_master_send_dma	1	1~2^15	NA	NA
    hal_i2c_master_receive_dma	NA	NA	1	1~2^15
    hal_i2c_master_send_to_receive_dma	1	1~2^15	1	1~2^15

• Waveform pattern supported by the APIs
  The 4 parameters(send_packet_length(Ns), send_bytes_in_one_packet(Ms), receive_packet_length(Nr), receive_bytes_in_one_packet(Mr) will also affect the transaction packet. The relationship between transaction packet and these 4 parameters is shown below.
  • Ns is the send_packet_length.
  • Ms is the send_bytes_in_one_packet.
  • Nr is the receive_packet_length.
  • Mr is the receive_bytes_in_one_packet.

    API	transaction packet format
    hal_i2c_master_send_polling
    hal_i2c_master_receive_polling
    hal_i2c_master_send_to_receive_polling
    hal_i2c_master_send_dma
    hal_i2c_master_receive_dma
    hal_i2c_master_send_to_receive_dma

Functions
hal_i2c_status_t	hal_i2c_master_init (hal_i2c_port_t i2c_port, hal_i2c_config_t *i2c_config)
	This function initializes the I2C master before starting a transaction. More...
hal_i2c_status_t	hal_i2c_master_deinit (hal_i2c_port_t i2c_port)
	This function releases the I2C master after the transaction is over. More...
hal_i2c_status_t	hal_i2c_master_set_frequency (hal_i2c_port_t i2c_port, hal_i2c_frequency_t frequency)
	This function sets the transaction speed. More...
hal_i2c_status_t	hal_i2c_master_register_callback (hal_i2c_port_t i2c_port, hal_i2c_callback_t i2c_callback, void *user_data)
	This function registers a callback function while using DMA mode. More...
hal_i2c_status_t	hal_i2c_master_send_polling (hal_i2c_port_t i2c_port, uint8_t slave_address, const uint8_t *data, uint32_t size)
	This function sends data to I2C slave in polling mode. More...
hal_i2c_status_t	hal_i2c_master_send_dma (hal_i2c_port_t i2c_port, uint8_t slave_address, const uint8_t *data, uint32_t size)
	This function sends data to I2C slave in DMA mode. More...
hal_i2c_status_t	hal_i2c_master_receive_polling (hal_i2c_port_t i2c_port, uint8_t slave_address, uint8_t *buffer, uint32_t size)
	This function receives data from I2C slave in a polling mode. More...
hal_i2c_status_t	hal_i2c_master_receive_dma (hal_i2c_port_t i2c_port, uint8_t slave_address, uint8_t *buffer, uint32_t size)
	This function receives data from I2C slave in a DMA mode. More...
hal_i2c_status_t	hal_i2c_master_send_to_receive_polling (hal_i2c_port_t i2c_port, hal_i2c_send_to_receive_config_t *i2c_send_to_receive_config)
	This function sends data to and then receives data from I2C slave in a polling mode. More...
hal_i2c_status_t	hal_i2c_master_send_to_receive_dma (hal_i2c_port_t i2c_port, hal_i2c_send_to_receive_config_t *i2c_send_to_receive_config)
	This function sends data to and then receives data from I2C slave in a DMA mode. More...
hal_i2c_status_t	hal_i2c_master_get_running_status (hal_i2c_port_t i2c_port, hal_i2c_running_status_t *running_status)
	This function gets running status of the I2C master. More...

Modules
	Define
	Enum
	Struct
	Typedef

Function Documentation

hal_i2c_status_t hal_i2c_master_deinit

(

hal_i2c_port_t

i2c_port

)

This function releases the I2C master after the transaction is over.

Call this function, if the I2C is no longer in use.

Parameters

[in]

i2c_port

is the I2C master port number. The value is defined in hal_i2c_port_t.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_OK, the operation completed successfully.

Note

This function must be called when the I2C is no longer in use, release the I2C resource for the other users to use this I2C master.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_init()

hal_i2c_status_t hal_i2c_master_get_running_status	(	hal_i2c_port_t	i2c_port,
		hal_i2c_running_status_t *	running_status
	)

This function gets running status of the I2C master.

Call this function to check if the I2C is idle or not before transferring data. If it's not idle, then the resource is currently in use, delay the operation until the I2C is idle.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[out]	running_status	HAL_I2C_STATUS_BUS_BUSY, the I2C master is in busy status; HAL_I2C_STATUS_IDLE, the I2C master is in idle status; User can use it to transmit data immediately.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_OK, the operation completed successfully.

Example

Sample code, please refer to How to use this driver

hal_i2c_status_t hal_i2c_master_init	(	hal_i2c_port_t	i2c_port,
		hal_i2c_config_t *	i2c_config
	)

This function initializes the I2C master before starting a transaction.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	i2c_config	Is the configuration parameter to initialize the I2C. Details are described at hal_i2c_config_t.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, an invalid transfer_frequency is given;
HAL_I2C_STATUS_OK, the operation completed successfully. HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Note

hal_i2c_master_deinit() must be called when the I2C is no longer in use, release the I2C resource for the other users to use this I2C master. Please DO NOT call hal_i2c_master_init() in interrupt handler, it may cause deadlock. In a multi-task applications, if hal_i2c_master_init() returns error HAL_I2C_STATUS_ERROR_BUSY, it is suggested to call functions that can yield CPU and try again later.

Example

hal_i2c_status_t i2c_master_init(void)
{
  hal_i2c_port_t i2c_port;
  hal_i2c_config_t i2c_config;
  hal_i2c_status_t error_status;

  uint32_t try_times = 0;

  i2c_port = HAL_I2C_MASTER_0;
  i2c_config.frequency = HAL_I2C_FREQUENCY_400K;

  while (try_times < 10) {
      error_status = hal_i2c_master_init(i2c_port, &i2c_config);
      if (error_status == HAL_I2C_STATUS_ERROR_BUSY) {
          vTaskDelay((portTickType)100 / portTICK_RATE_MS);
          try_times ++;
      } else {
        break;
      }
   }
  return error_status;
}

See also

hal_i2c_master_deinit()

hal_i2c_status_t hal_i2c_master_receive_dma	(	hal_i2c_port_t	i2c_port,
		uint8_t	slave_address,
		uint8_t *	buffer,
		uint32_t	size
	)

This function receives data from I2C slave in a DMA mode.

This function will return a value immediately after configuring the hardware registers. For more details of DMA mode, see DMA mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter. Note, not all masters support DMA mode. For more details about DMA mode, see hal_i2c_port_t.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	slave_address	is the I2C slave address.
[out]	buffer	is the data buffer to receive.
[in]	size	is the data size to receive. The maximum value is HAL_I2C_MAXIMUM_DMA_TRANSACTION_SIZE.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_receive_polling()

hal_i2c_status_t hal_i2c_master_receive_polling	(	hal_i2c_port_t	i2c_port,
		uint8_t	slave_address,
		uint8_t *	buffer,
		uint32_t	size
	)

This function receives data from I2C slave in a polling mode.

This function will not return a value until the transaction is finished. For more details about polling mode, see polling mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	slave_address	is the I2C slave address.
[out]	buffer	is the data buffer to receive.
[in]	size	is the data size to receive. The maximum value is HAL_I2C_MAXIMUM_POLLING_TRANSACTION_SIZE.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR, a hardware error occurred during the transaction.
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_receive_dma()

hal_i2c_status_t hal_i2c_master_register_callback	(	hal_i2c_port_t	i2c_port,
		hal_i2c_callback_t	i2c_callback,
		void *	user_data
	)

This function registers a callback function while using DMA mode.

The callback function will be called at I2C ISR routine after the I2C triggers an interrupt. Always call this function to register a callback function while using DMA mode. Refer to Software architecture of the I2C for DMA architecture.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	i2c_callback	is the user-defined callback function called at I2C ISR routine.
[in]	user_data	is a user-defined input data returned during the callback function's call. See the last parameter of hal_i2c_callback_t.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL function pointer is given by user;
HAL_I2C_STATUS_OK,the operation completed successfully.

Example

Sample code, please refer to How to use this driver

hal_i2c_status_t hal_i2c_master_send_dma	(	hal_i2c_port_t	i2c_port,
		uint8_t	slave_address,
		const uint8_t *	data,
		uint32_t	size
	)

This function sends data to I2C slave in DMA mode.

This function returns a value immediately after configuring the hardware registers. For more details about DMA mode, see DMA mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter. Note, not all I2C masters support DMA mode. For more details about DMA mode,see hal_i2c_port_t.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	slave_address	is the I2C slave address.
[in]	data	is the data buffer to send.
[in]	size	is the data size to send. The maximum value is HAL_I2C_MAXIMUM_DMA_TRANSACTION_SIZE.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, an NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_send_polling()

hal_i2c_status_t hal_i2c_master_send_polling	(	hal_i2c_port_t	i2c_port,
		uint8_t	slave_address,
		const uint8_t *	data,
		uint32_t	size
	)

This function sends data to I2C slave in polling mode.

This function will not return until the transaction is complete. For more details about polling mode, see polling mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	slave_address	is the I2C slave address.
[in]	data	is the data buffer to send.
[in]	size	is the data size to send. The maximum value is HAL_I2C_MAXIMUM_POLLING_TRANSACTION_SIZE.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR, a hardware error occurred during the transaction.
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_send_dma()

hal_i2c_status_t hal_i2c_master_send_to_receive_dma	(	hal_i2c_port_t	i2c_port,
		hal_i2c_send_to_receive_config_t *	i2c_send_to_receive_config
	)

This function sends data to and then receives data from I2C slave in a DMA mode.

This function returns immediately after configuring the hardware registers. For more details of DMA mode, see DMA mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter. Note, not all masters support DMA mode. For more details about DMA mode, see DMA mode of hal_i2c_port_t.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in,out]	i2c_send_to_receive_config	is the configuration parameter for this API for both send and receive.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_send_to_receive_polling()

hal_i2c_status_t hal_i2c_master_send_to_receive_polling	(	hal_i2c_port_t	i2c_port,
		hal_i2c_send_to_receive_config_t *	i2c_send_to_receive_config
	)

This function sends data to and then receives data from I2C slave in a polling mode.

This function does not return until the transaction is finished. For more details about polling mode, see polling mode in Supported features chapter. For details about transaction length and transaction waveform pattern, see Transaction Length And transaction packet of APIs chapter.

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in,out]	i2c_send_to_receive_config	is the configuration parameter for this API for both send and receive.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, a NULL buffer pointer is given by user;
HAL_I2C_STATUS_OK, the operation completed successfully;
HAL_I2C_STATUS_ERROR, a hardware error occurred during the transaction.
HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

Sample code, please refer to How to use this driver

See also

hal_i2c_master_send_to_receive_dma()

hal_i2c_status_t hal_i2c_master_set_frequency	(	hal_i2c_port_t	i2c_port,
		hal_i2c_frequency_t	frequency
	)

This function sets the transaction speed.

Apply this function to change the transaction speed without using hal_i2c_master_init().

Parameters

[in]	i2c_port	is the I2C master port number. The value is defined in hal_i2c_port_t.
[in]	frequency	is an enum value defined in hal_i2c_frequency_t. Only value of type hal_i2c_frequency_t is accepted.

Returns

HAL_I2C_STATUS_INVALID_PORT_NUMBER, an invalid port number is given;
HAL_I2C_STATUS_INVALID_PARAMETER, an invalid speed is given;
HAL_I2C_STATUS_OK, the operation completed successfully. HAL_I2C_STATUS_ERROR_BUSY, the I2C bus is in use.

Example

ret = hal_i2c_master_config_speed(HAL_I2C_MASTER_1,HAL_I2C_SPEED_400K);

See also

hal_i2c_master_init()