1   2   3   4           5   6   7   8   9   10  11  12  13  14 
"a" "b" CR  LF          "_" "_" "D" "A" "T" "A" "_" "_" CR  LF
"a" "b" CR  LF  CR  LF  "_" "_" "D" "A" "T" "A" "_" "_" CR  LF
1   2   3   4   5   6   7   8   9   10  11  12  13  14  15  16