Library Description

The library covers all the necessary functions to control Expand 8 click board.
The library performs a standard SPI interface communication.

Key functions:

• void expand8_write_data ( uint8_t addr, uint8_t tx_data ); - Generic write data function.
• uint8_t expand8_read_data ( uint8_t addr ); - Generic read data function.
• EXPAND8_RETVAL_T expand8_set_port ( uint8_t sel_port, uint8_t sel_imped ); - Set port function.

Examples description

The application is composed of three sections :

• System Initialization - Initializes SPI, set the CS pin as outputs
   and begins to write log.
• Application Initialization - Initialization driver enables - SPI,
   also, write a log.
• Application Task - (code snippet) This is an example that demonstrates the use of the Expand 8 click board.
   Expand 8 click by toggling each of 10 available ports every 1 second.
   Results are being sent to the Usart Terminal where you can track their changes.

void application_task ( )
{

    expand8_set_port( select_port,
                      EXPAND8_SET_LOW_IMPEDANCE );
   
    mikrobus_logWrite( "     Port P", _LOG_TEXT );
    ByteToStr( select_port, demo_text );
    Ltrim( demo_text );
    mikrobus_logWrite( demo_text, _LOG_TEXT );
    mikrobus_logWrite( " ON", _LOG_LINE );
    mikrobus_logWrite( "- - - - - - - - - - -", _LOG_LINE );
    Delay_ms( 1000 );
        
    expand8_set_port( select_port,
                      EXPAND8_SET_HIGH_IMPEDANCE );
    mikrobus_logWrite( "     Port P", _LOG_TEXT );
    ByteToStr( select_port, demo_text );
    Ltrim( demo_text );
    mikrobus_logWrite( demo_text, _LOG_TEXT );
    mikrobus_logWrite( " OFF", _LOG_LINE );
    mikrobus_logWrite( "---------------------", _LOG_LINE );
    Delay_ms( 1000 );

    select_port++;

    if ( select_port > EXPAND8_ADDR_OUT_LVL_PORT_P9 )
    {
        select_port = EXPAND8_ADDR_OUT_LVL_PORT_P0;
    }
}

Other mikroE Libraries used in the example:

• SPI
• 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.