char t1 = buffer[1];
char t2 = buffer[2];
char t3 = buffer[3];
std::cout << t1 << t2 << t3 << std::endl;
QString strt123;
strt123 += t1;
strt123 += t2;
strt123 += t3;
int i123 = strt123.toInt();
std::cout << i123 << std::endl;