function login_mr(){
  id_document="log";
  mr_1=document.getElementById('sub_mr').value;
  mr_2=document.getElementById('pass').value;
request.open('POST', 'login.php',true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded'); 
request.onreadystatechange = parseInfo; 
request.send('sub=' + mr_1 + '&pass=' + mr_2);
}