I2C MUX 2 Click

I2C MUX 2 Click is a quad bidirectional translating I2C and SMBus switch with reset and interrupt functions, intended for applications with I2C slave address conflicts. It features a quad bidirectional translating switch controlled via the I2C bus, labeled as TCA9545A from Texas Instruments. Four interrupt inputs (INT3–INT0), one for each of the downstream pairs, are provided on Click board. One interrupt (INT) output acts as an AND of the four interrupt inputs.

Click Product page

Click library

• Author : MikroE Team
• Date : Feb 2020.
• Type : I2C type

Software Support

We provide a library for the I2cMux2 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly form compilers IDE(recommended way), or downloaded from our LibStock, or found on mikroE github account.

Library Description

This library contains API for I2cMux2 Click driver.

Standard key functions :

• i2cmux2_cfg_setup Config Object Initialization function.

  void i2cmux2_cfg_setup ( i2cmux2_cfg_t *cfg ); 

• i2cmux2_init Initialization function.

  err_t i2cmux2_init ( i2cmux2_t *ctx, i2cmux2_cfg_t *cfg );

Example key functions :

• i2cmux2_hw_reset This function resets I2C MUX 2 Click board by clearing the RST pin for 100ms.

  void i2cmux2_hw_reset ( i2cmux2_t *ctx );

• i2cmux2_set_channel Function sets channel of the I2C MUX 2 Click board.

  void i2cmux2_set_channel ( i2cmux2_t *ctx, uint8_t channel, uint8_t ch_slave_address );

• i2cmux2_generic_read This function reads data from the desired register.

  void i2cmux2_generic_read ( i2cmux2_t *ctx, uint8_t reg, uint8_t *data_buf, uint8_t len );

Examples Description

This example demonstrates the use of the I2C MUX 2 Click board.

The demo application is composed of two sections :

Application Init

Initializes the driver, performs the device reset, and makes an initial log.

void application_init ( void )
{
    log_cfg_t log_cfg;
    i2cmux2_cfg_t cfg;

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.
    i2cmux2_cfg_setup( &cfg );
    I2CMUX2_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    i2cmux2_init( &i2cmux2, &cfg );

    Delay_ms ( 100 );
    log_printf( &logger, "I2C MUX 2 Click driver init\r\n");
    log_printf( &logger, "---------------------------------------\r\n");
    Delay_ms ( 100 );

    i2cmux2_hw_reset( &i2cmux2 );
    log_printf( &logger, "I2C MUX 2 Click HW reset\r\n");
    log_printf( &logger, "---------------------------------------\r\n");
    Delay_ms ( 100 );
}

Application Task

In this example, we read the device ID register of the connected Click boards. Channel 0 : 6DOF IMU 11 Click [slave address: 0x0E; reg: 0x00; id val.: 0x2D], Channel 1 : Altitude Click [slave address: 0x60; reg: 0x0C; id val.: 0xC4], Channel 2 : 6DOF IMU 9 Click [slave address: 0x69; reg: 0x75; id val.: 0xA9], Channel 3 : Compass 3 Click [slave address: 0x30; reg: 0x2F; id val.: 0x0C]. All data logs write on USB UART changes every 2 sec.

void application_task ( void )
{
    log_printf( &logger, "  CH  |   ID   |  INT \r\n" );
    log_printf( &logger, "----------------------\r\n" );

#ifdef ENABLE_CHANNEL_0
    // SET CHANNEL 0: 6DOF IMU 11 Click
    i2cmux2_set_channel( &i2cmux2, I2CMUX2_CMD_SET_CH_0, 0x0E );
    Delay_ms ( 100 );
    i2cmux2_generic_read( &i2cmux2, 0x00, &rx_data, 1 );
    display_log( I2CMUX2_CMD_SET_CH_0 );
#endif

#ifdef ENABLE_CHANNEL_1
    // SET CHANNEL 1: Altitude Click
    i2cmux2_set_channel( &i2cmux2, I2CMUX2_CMD_SET_CH_1, 0x60 );
    Delay_ms ( 100 );
    i2cmux2_generic_read( &i2cmux2, 0x0C, &rx_data, 1 );
    display_log( I2CMUX2_CMD_SET_CH_1 );
#endif

#ifdef ENABLE_CHANNEL_2
    // SET CHANNEL 2: 6DOF IMU 9 Click
    i2cmux2_set_channel( &i2cmux2, I2CMUX2_CMD_SET_CH_2, 0x69 );
    Delay_ms ( 100 );
    i2cmux2_generic_read( &i2cmux2, 0x75, &rx_data, 1 );
    display_log( I2CMUX2_CMD_SET_CH_2 );
#endif

#ifdef ENABLE_CHANNEL_3
    // SET CHANNEL 3: Compass 3 Click
    i2cmux2_set_channel( &i2cmux2, I2CMUX2_CMD_SET_CH_3, 0x30 );
    Delay_ms ( 100 );
    i2cmux2_generic_read( &i2cmux2, 0x2F, &rx_data, 1 );
    display_log( I2CMUX2_CMD_SET_CH_3 );
#endif

    log_printf( &logger, "----------------------\r\n" );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
} 

Note

Disable all unconnected channels from the example using ENABLE_CHANNEL_x macros below to prevent the I2C bus from blocking waiting for a device response.

The full application code, and ready to use projects can be installed directly form compilers IDE(recommneded) or found on LibStock page or mikroE GitHub accaunt.

Other mikroE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.I2cMux2

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. The terminal available in all Mikroelektronika compilers, or any other terminal application of your choice, can be used to read the message.