Read/Write EPCS64 flash from Nios II

Hi all,

Actually, I'm trying to write/read my flash device using the HAL functions.

After opening the device, I write into the EPCS64 using alt_write_flash_block, then i read it using alt_read_flash.

The problem i have is that the data read/ written showen in the Nios II console are not the same.

The code for writing and reading is below:

int Write_flash( alt_flash_fd* fd, float *Ks_para,int test_offset)
{
    int i;
    int ret_code = 0;
    alt_u8 *ptr_ks=(alt_u8*) Ks_para;
    int test_length = sizeof(Ks_para);
    // before writing in a sector, we should erase it before
    ret_code=alt_epcq_controller_erase_block(fd, test_offset);
    if(!ret_code){
        for(i=0;i<test_length;i++){
            printf( "data_written= 0x%08x\n\r",i,ptr_ks);
        }
        ret_code=alt_write_flash_block(fd,test_offset,test_offset,ptr_ks,test_length);
    }
    if (ret_code)
    {
            printf( "\nERROR: function alt_write_flash failed. ret_code %d\n",ret_code);
            return ret_code;
    }
    return ret_code;
}

float Read_flash( alt_flash_fd* fd,int test_offset)
{
    int test_length = 4;
    alt_u8 data_read;
    int i=0;
    union conv2float read_flash;
    float Ks_para=0.0;
    int ret_code = 0;
        if (!ret_code)
        {
            ret_code=alt_read_flash(fd, test_offset, data_read, test_length);
            if(!ret_code)
            {
                for(i=0;i<4;i++){
                    read_flash.V_In=data_read;
                    printf( "Flash+%d= 0x%08x\n\r",i,read_flash.V_In);
                }
                Ks_para=read_flash.V_Fl;
                
            }
        }
        if (ret_code)
        {
            printf( "\nERROR: function READ failed. ret_code %d\n",ret_code);
        }
    return Ks_para;
}

Do you have an idea why ?

Thank you in advance.

Best regards