Library Description

The library covers all the necessary functions to control OneWire I2C click board. 
The library performs the communication with the device via 1-Wire protocol by writing to registers and by reading from registers.

Key functions:

• void onewirei2c_reset() - Reset function.
• uint16_t onewirei2c_crc16( uint8_t *pData, uint8_t len ) - CRC calculation function.

Examples description

The application is composed of the three sections :

• System Initialization - Initializes GPIO structures and start to write log.
• Application Initialization -  Initialization driver enables - GPIO, reset OneWire I2C click and also write log.
• Application Task - (code snippet) This is an example which demonstrates the use of OneWire I2C click board. OneWire I2C click communicates with register via One Wire protocol by the write to register and read from the register and communicating with Thermo 4 click. OneWire I2C will first send to the Thermo 4 click address and register address via I2C, and then read 2 bytes of data from that click. Results are being sent to the Usart Terminal where you can track their changes. All data logs write on USB uart changes for every 1 sec.

void applicationTask() 
{
    onewirei2c_skipRom ();
    
    CRCPacket[ 0 ] = 0x5A;
    CRCPacket[ 1 ] = 0x90;
    CRCPacket[ 2 ] = 0x01;
    CRCPacket[ 3 ] = 0x00;

    CRCResult = onewirei2c_crc16( &CRCPacket, 4 );

    CRCPacket[ 0 ] = CRCResult & 0x00FF;
    CRCPacket[ 1 ] = ( CRCResult >> 8 ) & 0x00FF;

    onewirei2c_oneWireWrite( 0x5A );
    onewirei2c_oneWireWrite( 0x90 );
    onewirei2c_oneWireWrite( 0x01 );
    onewirei2c_oneWireWrite( 0x00 );

    onewirei2c_oneWireWrite( CRCPacket[ 0 ] );
    onewirei2c_oneWireWrite( CRCPacket[ 1 ] );
    
    owStatus = onewirei2c_oneWireRead();
    owStatus >>= 1;
    writeStatus = onewirei2c_oneWireRead();
    writeStatus >>= 1;

    onewirei2c_skipRom();

    CRCPacket[ 0 ] = 0x87;
    CRCPacket[ 1 ] = 0x91;
    CRCPacket[ 2 ] = 0x02;

    CRCResult = onewirei2c_crc16( &CRCPacket, 3 );

    CRCPacket[ 0 ] = CRCResult & 0x00FF;
    CRCPacket[ 1 ] = ( CRCResult >> 8 ) & 0x00FF;

    onewirei2c_oneWireWrite( 0x87 );
    onewirei2c_oneWireWrite( 0x91 );
    onewirei2c_oneWireWrite( 0x02 );

    onewirei2c_oneWireWrite( CRCPacket[ 0 ] );
    onewirei2c_oneWireWrite( CRCPacket[ 1 ] );

    owStatus = onewirei2c_oneWireRead();

    readData[ 0 ] = onewirei2c_oneWireRead();
    readData[ 1 ] = onewirei2c_oneWireRead();

    owStatus >>= 1;
    owStatus |= ( ( 0x01 & readData[ 0 ] ) * 0x80 );
    owStatus *= 0x80;

    readData[ 0 ] >>= 1;
    readData[ 0 ] |= ( ( 0x01 & readData[ 1 ] ) * 0x80 );

    ByteToStr( readData[ 0 ], logText );
    mikrobus_logWrite( " Temperature : ", _LOG_TEXT );
    mikrobus_logWrite( logText, _LOG_TEXT );

    if ( readData[ 1 ] > 0x7F )
    {
        mikrobus_logWrite( ".5 ",_LOG_TEXT );
    }
    else
    {
        mikrobus_logWrite( ".0 ", _LOG_TEXT );
    }

    mikrobus_logWrite( degCel, _LOG_LINE );

    Delay_1sec();
    Delay_1sec();    
}        

Other mikroE Libraries used in the example:

• One_Wire
• UART​
• Conversion

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