RS485 5V click

RS485 click 5V is an RS422/485 transceiver Click board™, which can be used as an interface between the TTL level UART and the RS422/485 communication bus. It features a half-duplex communication capability, bus Idle, open, and short-circuit detection, thermal shutdown, and more. It is well suited for transmitting data packets over long distances and noisy areas, using the twisted wire bus, which offers good electromagnetic interferences (EMI) immunity.

click Product page

Click library

• Author : Stefan Ilic
• Date : Jun 2021.
• Type : UART type

Software Support

We provide a library for the RS4855V 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 from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for RS4855V Click driver.

Standard key functions :

• rs4855v_cfg_setup Config Object Initialization function.

  void rs4855v_cfg_setup ( rs4855v_cfg_t *cfg );

• rs4855v_init Initialization function.

  err_t rs4855v_init ( rs4855v_t *ctx, rs4855v_cfg_t *cfg );

Example key functions :

• rs4855v_generic_read This function reads a desired number of data bytes by using UART serial interface.

  err_t rs4855v_generic_read ( rs4855v_t *ctx, char *data_buf, uint16_t max_len );

• rs4855v_send_command This function sends a command by using UART serial interface.

  void rs4855v_send_command ( rs4855v_t *ctx, char *command );

Example Description

This example reads and processes data from RS485 5V clicks.

The demo application is composed of two sections :

Application Init

Initializes driver and wake-up module.

void application_init ( void ) {
    log_cfg_t log_cfg;
    rs4855v_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 );

    //  Click initialization.

    rs4855v_cfg_setup( &cfg );
    RS4855V_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    rs4855v_init( &rs4855v, &cfg );
    log_info( &logger, " Application Task " );
    Delay_ms ( 100 );

#ifdef DEMO_APP_TRANSMITTER
    log_printf( &logger, "------------------\r\n" );
    log_printf( &logger, "    Send data:    \r\n" );
    log_printf( &logger, "      MikroE      \r\n" );
    log_printf( &logger, "------------------\r\n" );
    log_printf( &logger, "  Transmit data   \r\n" );
    Delay_ms ( 1000 );

#endif

#ifdef DEMO_APP_RECEIVER 
    log_printf( &logger, "------------------\r\n" );

    log_printf( &logger, "   Receive data  \r\n" );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
#endif

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

Application Task

Reads the received data and parses it.

void application_task ( void ) {  
#ifdef DEMO_APP_RECEIVER 

    rs4855v_process( );
    if ( current_rsp_buf > 0 ) {
        log_printf( &logger, "%s", current_rsp_buf );
        rs4855v_clear_current_rsp_buf( );
    }

#endif 

#ifdef DEMO_APP_TRANSMITTER

    rs4855v_send_command( &rs4855v, &demo_message[ 0 ] );
    log_printf( &logger, "\t%s",  &demo_message[ 0 ] );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    log_printf( &logger, "------------------\r\n" ); 

#endif   
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.RS4855V

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. UART terminal is available in all MikroElektronika compilers.