Unassemble command

    Purpose:  Unassembles instructions (translates the contents of memory
              into assembler-like statements) and displays their addresses
              and hexadecimal values, together with assembler-like state-
              ments. For example, a display might look like this:

              04BA:0100  206472    AND  [SI+72],AH
              04BA:0103  FC        CLD
              04BA:0104  7665      JBE 016B

    Format:   U address      or      U range

    Remarks:  The number of bytes unassembled depends on your system dis-
              play format (whether 40 or 80 columns), and which option you
              use with the Unassemble command.

              Notes:

              1.  In all cases, the number of bytes unassembled and dis-
                  played may be slightly more than either the amount re-
                  quested or the default amount. This happens because the
                  instructions are of variable lengths; therefore, to un-
                  assemble the last instruction may include more bytes
                  than expected.

              2.  Make sure that the address parameters refer to locations
                  containing valid CPU instruction codes. If you specify
                  an address that does not contain the first byte of a
                  valid instruction, the display will be erroneous.

              3.  If you enter only an offset for the starting address,
                  the U command assumes the segment contained in the CS
                  register.


              Option 1                                                    

              Use this option to either unassemble instructions without
              specifying an address, or to assemble instructions begin-
              ning with a specified address. For example

              U
                 or
              U address

              Sixteen bytes are unassembled with a 40-column display.
              Thirty-two bytes are unassembled while in 80-column mode.

              Instructions are unassembled beginning with the specified
              address.

              If you do not specify an address, the U command assumes
              the starting address is the location following the last
              instruction unassembled by a previous U command. Thus, it
              is possible to unassemble consecutive locations, producing
              continuous unassembled displays, by entering consecutive U
              commands without parameters.

              If no previous U command is entered, the location is offset
              0100h into the segment originally initialized in the seg-
              ment registers by DEBUG.


              Option 2                                                    

              Use this option to unassemble instructions in a specified
              address range. For example:

              U range

              All instructions in the specified address range are unassem-
              bled, regardless of the system display format.

                 Note:
                 If you specify an ending address, enter it with only an
                 offset value.

              For example:

              U04ba:0100 108

              The display response might be:

              04BA:0100  206472       AND  [SI+72],AH
              04BA:0103  FC           CLD
              04BA:0104  7665         JBE  016B
              04BA:0106  207370       AND  [BP+DI+70],DH

              The same display appears if you enter:

              U04BA:100 L 7
                 or
              U 04BA:100 L 8
                 or
              U 04BA:100 L 9