Library Description

Library provides functions for communication over UART module with the device, controlling RE( Receiver Output Enable ) and DE( Driver Output Enable ) pins state.

Key functions:

• void rs4855_write_byte ( uint8_t input ) - Function for writing data via UART module.
• uint8_t rs4855_read_byte( ) - Function for reading data via UART module.
• void rs4855_set_de_state( uint8_t state ) - Function for setting DE pin state.
• void rs4855_set_re_state( uint8_t state ) - Function for setting RE pin state.

Examples description

The application is composed of three sections :

• System Initialization - Intializes UART module
• Application Initialization - Driver intialization
• Application Task - Choose one mode (read or write) of task. If you reading it checks if data is ready to be read and then reads one byte and if you are wiriting send data via UART.

void application_task ( )
{
    char tmp;
    uint8_t drdy_flag;

    if ( app_mode == APP_MODE_RECEIVER )
    {
        // RECEIVER - UART polling 

        drdy_flag = rs4855_byte_ready( );

        if ( 1 == drdy_flag )
        {
            tmp = rs4855_read_byte( );
            mikrobus_logWrite( &tmp, _LOG_BYTE );
        }
    }
    else
    {
        // TRANSMITER - TX each 2 sec
      
        for ( tmp = 0; tmp < 9; tmp++ )
        {
            rs4855_write_byte( demo_message_data[ tmp ] );
            mikrobus_logWrite( ">> MESSAGE SENT <<", _LOG_LINE );
        }
        Delay_ms(2000);
    }
}

Other mikroE Libraries used in the example:

• UART

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.