http://margo.student.utwente.nl/el/
pc/help

debugtut  .zip      DOS debug.exe tutorial.
help      .zip  !   DOS help about asm, c, hardware, interrupts and more (old but good).
lv286     .zip      LANGUAGE WINDOW USERS GUIDE (DOS TSR with all 80286 code info).
lv86      .zip      LANGUAGE WINDOW USERS GUIDE (DOS TSR with all 8086/88,186/188
                    code info).
techhelp  .zip  !   Another usefull DOS help app about asm, int, hardware and more.