RS485 2 Click

RS485 2 Click 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.

Click Product page

Click library

• Author : MikroE Team
• Date : Apr 2020.
• Type : UART type

Software Support

We provide a library for the Rs4852 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 Rs4852 Click driver.

Standard key functions :

• Config Object Initialization function.

  void rs4852_cfg_setup ( rs4852_cfg_t *cfg );

• Initialization function.

  RS4852_RETVAL rs4852_init ( rs4852_t ctx, rs4852_cfg_t cfg );

Example key functions :

• Generic read function.

  int32_t rs4852_generic_read ( rs4852_t ctx, char data_buf, uint16_t max_len );

• Generic write function.

  void rs4852_generic_write ( rs4852_t ctx, char data_buf, uint16_t len );

• Set DE ( cs ) pin state.

  void rs4852_set_de_pin ( rs4852_t *ctx, uint8_t state );

Examples Description

This example reads and processes data from RS485 2 clicks.

The demo application is composed of two sections :

Application Init

Initializes the driver and enables the selected mode.

void application_init ( void )
{
    log_cfg_t log_cfg;
    rs4852_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.

    rs4852_cfg_setup( &cfg );
    RS4852_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    rs4852_init( &rs4852, &cfg );
    Delay_ms ( 100 );

#ifdef DEMO_APP_RECEIVER
    rs4852_set_re_pin( &rs4852, RS4852_ENABLE_RE );
    rs4852_set_de_pin( &rs4852, RS4852_DISABLE_DE );
    log_info( &logger, "---- Receiver mode ----" );
#endif    
#ifdef DEMO_APP_TRANSMITTER
    rs4852_set_de_pin( &rs4852, RS4852_ENABLE_DE );
    rs4852_set_re_pin( &rs4852, RS4852_DISABLE_RE );
    log_info( &logger, "---- Transmitter mode ----" );
#endif    
    Delay_ms ( 100 );
}

Application Task

Depending on the selected mode, it reads all the received data or sends the desired message every 2 seconds.

void application_task ( void )
{
#ifdef DEMO_APP_RECEIVER
    rs4852_process( );
#endif    

#ifdef DEMO_APP_TRANSMITTER
    rs4852_generic_write( &rs4852, TEXT_TO_SEND, strlen( TEXT_TO_SEND ) );
    log_info( &logger, "---- Data sent ----" );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
#endif  
} 

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.Rs4852

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.