Library Description

The library covers all the necessary functions that enables the usage of the I2C MUX 3 click board. User can set one of 8 channels by writing to devices control register and check it by reading, or use the function to set it directly. User can also use sequential read and write function to comunicate with the devices sonnected to the selected channel.

Key functions:

• uint8_t n_bytes ); - Function is used to write a sequential data starting from the targeted 8-bit register address of the device connected to the desired channel of the I2C MUX 4 click board.
• uint8_t n_bytes ) - Function is used to read a sequential data starting from the targeted 8-bit register address of the device connected to the desired channel of the I2C MUX 4 click board.
• void i2cmux3_ch_sel ( uint8_t sel_ch ); - Function is used to select communication channel.

Examples description

The application is composed of three sections :

• System Initialization - Initializes I2C module, LOG structure and sets RST pin as output.
• Application Initialization - Initalizes I2C driver, preforms hardware reset and makes an initial log.
• Application Task - This example shows the capabilities of the I2C MUX 3 click by reading device ID values from eight different click boards and displaying the readings via USART terminal. Some of the used click boards have the same I2C slave addresses, while others do not.
• Application Note - Click boards used in this example : 6DOF IMU 12 click - https://www.mikroe.com/6dof-imu-12-click RTC 10 click - https://www.mikroe.com/rtc-10-click Surface Temp click - https://www.mikroe.com/surface-temp-click Spectrometer click - https://www.mikroe.com/spectrometer-click Compass 3 click - https://www.mikroe.com/compass-3-click Color 3 click - https://www.mikroe.com/color-3-click 6DOF IMU 11 click - https://www.mikroe.com/6dof-imu-11-click Heart Rate 4 click - https://www.mikroe.com/heart-rate-4-click

void application_task ( )
{
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    mikrobus_logWrite( "ID values by click board:", _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    mikrobus_logWrite( "", _LOG_LINE );

    i2cmux3_ch_sel( 0 );
    i2cmux3_rd_slv ( 0x68, 0x00, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " 6DOF IMU 12  : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );

    i2cmux3_ch_sel( 1 );
    i2cmux3_rd_slv ( 0x68, 0x0F, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " RTC 10       : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );

    i2cmux3_ch_sel( 2 );
    i2cmux3_rd_slv ( 0x48, 0x0B, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " Surface Temp : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );
    
    i2cmux3_ch_sel( 3 );
    i2cmux3_rd_slv ( 0x39, 0x92, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " Spectrometer : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );
    
    i2cmux3_ch_sel( 4 );
    i2cmux3_rd_slv ( 0x30, 0x2F, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " Compass 3    : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );
    
    i2cmux3_ch_sel( 5 );
    i2cmux3_rd_slv ( 0x29, 0x12, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " Color 3      : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );
    
    i2cmux3_ch_sel( 6 );
    i2cmux3_rd_slv ( 0x0E, 0x00, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " 6DOF IMU 11  : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );
    
    i2cmux3_ch_sel( 7 );
    i2cmux3_rd_slv ( 0x57, 0xFF, &id_val, 1 );
    ByteToHex( id_val, log_txt );
    Ltrim( log_txt );
    mikrobus_logWrite( " Heart Rate 4 : 0x", _LOG_TEXT );
    mikrobus_logWrite( log_txt, _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 100 );

    mikrobus_logWrite( "", _LOG_LINE );
    mikrobus_logWrite( "-------------------------", _LOG_LINE );
    Delay_ms( 3000 );
}

Other mikroE Libraries used in the example:

• I2C
• UART
• Conversions

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.