u32 crc(u32 *ptr, u32 size, u32 sumadr, u32 sh1, u32 sh2)
{
    u32 sum = 0;
    sumadr /= 4;

    for (int i = 0; i < (size / 4); i++)
    {
        if (i == sumadr)
            continue;
        sum = sum ^ (ptr[i] << sh1) ^ (sum >> sh2) | 0x80;
    }
    return sum;
}