INS         Input String From Port  (186/286/386)    Flags: O D I T S Z A P C

INS [ES:]destination, DX

           Logic:          destination . source port
                           if DF = 0 then
                               DI . DI + delta
                           else
                               DI . DI - delta

     The INS instructions lets you read a string from a port. The destination
     string is pointed to by ES:DI (even if a destination operand is given).
     The input port number must be in DX. If the direction flag is set, DI is
     decremented. If it is not set, DI is incremented.

     To use INS, the destination operand must be provided so the assembler
     knows the size of each data item. Segment overrides are allowed.

  --------------------------------------------------------------------------
   Operands                   Clocks   Transfers  Bytes  Example
   INS                        5         1 or 2      4    INS STRING2, DX
  --------------------------------------------------------------------------

        Note:          This instruction is usually used with a REP
                       prefix. Load CX with the number of times to repeat
                       the instruction.