STM32 Learning Notes 6——Writing floating point numbers to the 24C02 chip

Method: Use union

(1) Union type definition

#define FLOAT_BYTE_NUM 4 //Number of bytes occupied by float type

//Floating point storage common

typedef union

{

    float value;

    uint8_t byte[FLOAT_BYTE_NUM];

} largeFloatData;

(2) Function definition

/********************************************************************************************************

Function name:

Function: Write a floating point number to the specified address

Details:

Input:

*********************************************************************************************************/

void Storage_WriteFloatNum( uint16_t addr, storFloatData data )

{

    uint8_t i = 0;

    uint8_t a = 0;

    for( i = 0; i <= FLOAT_BYTE_NUM - 1; i++ )

    {

      AT24CXX_WriteOneByte( addr + i, data.byte[i] );

    }

return;

}

/********************************************************************************************************

Function name:

Function: Read a floating point number from the specified address

Details:

Input:

*********************************************************************************************************/

storFloatData Storage_ReadFloatNum( uint16_t addr )

{

    uint8_t i = 0;

    largeFloatData read_data;

    for( i = 0; i <= FLOAT_BYTE_NUM - 1; i++ )

    {

        read_data.byte[i] = AT24CXX_ReadOneByte( addr + i );

    }

    return read_data;

}

(3) Use routines

largeFloatData data0={12.34};

largeFloatData data1;

Storage_WriteFloatNum(0,data0);

delay_ms(20);

data1 = Storage_ReadFloatNum(0);