FYI

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          TITLE:  USING SID INSTEAD OF DEBUG TO CREATE A UTILITY
   DOCUMENT ID#:  FYI-M-1115
           DATE:  06JAN93
        PRODUCT:  DR DOS
PRODUCT VERSION:  6.0
     SUPERSEDES:  13APR92

        SYMPTOM:  NEED TO TRANSLATE DEBUG INSTRUCTIONS INTO SID

  ISSUE/PROBLEM:  Many publications and bulletin board services distribute
scripts written in DEBUG to create various utilities.  To make use of these
scripts in DR DOS the script must be generated in SID.

       SOLUTION:  Below is a generic listing of a typical DEBUG script and the
steps that are used to adjust it so that the DR DOS SID utility will produce
the same results.

Typically, DEBUG scripts follow this pattern: DEBUG first establishes the name
of the file.  The "A" command is used to start assembling the instruction.
DEBUG defaults to an offset of 100.  Then the instructions for the utility
itself are listed. Finally, using the "RCX" command DEBUG is instructed as to
how many bytes of information should be saved.

SID does not require the name of the file until the file is actually saved. In
SID, the "A100" command is the instruction that begins assembly at offset 100.
The instructions for the utility itself are listed next. These instructions are
the same under both DEBUG and SID.  When a file is saved using SID, the
beginning and ending addresses must be specified. The beginning address is 100. 
The ending address is 100 + the number of bytes to be saved minus 1 (In the
example below, the ending address is represented by the word END).

The arithmetic is in hexadecimal values, but it is possible to do the
calculations in SID using the "H" command.  (See the HEX NOTE below). The last
command is Quit. It is the same under both utilities.



GENERIC SCRIPT

DEBUG SCRIPT    SID SCRIPT              COMMENTS
-----------------------------------------------------------------
N filename.ext  (not required)         -SID uses file name when it is saved.
A               A100        ---------+ -Begin assembling instructions.
(instructions   (instructions        | -Use the original commands.
go              go                   |
here)           here)                |
                                     |
<CR>            <CR>                 | -<CR> to exit assembling
RCX             (not required)       | -DEBUG is preparing to save y bytes
y               (not required)       |   of data. +----------------+
W               Wfilename.ext,100,END| -SID writes|from offset 100 to END
                                     |    ( 100 + y - 1 = END )
                                     |       |
                                     +-------+
Q               Q                       -And Quit.


Below is an example of a script that will build BEEP.COM, a program that simply
beeps the speaker once. Notice again that the arithmetic is in hexadecimal. (If
that is something with which you are unfamiliar, see the HEX NOTE at the end of
this example.)


DEBUG SCRIPT    SID SCRIPT      COMMENTS
-----------------------------------------------------------------N BEEP.COM     
(not required)          SID saves file name at end
A               A100        --------+   Begin assembling instructions
MOV AH,2        MOV AH,2            |   Use the original commands
MOV DL,07       MOV DL,07           |
INT 21          INT 21              |
MOV AH,4C       MOV AH,4C           |
INT 21          INT 21              |
<CR>            <CR>                |   <CR> to exit assembling
RCX             (not required)      |   DEBUG is preparing to save 10 (A Hex)
A               (not required)      |   of data.  +----------------+
W               WKEYD.COM,100,109   |   SID writes|from offset 100 to 109
Q               Q                   |     ( 100 + A - 1 = 109 )
                                    |        |
                                    +--------+


HEX NOTE:  SID can do the hex math for you. In the above example,  to do the
first addition ( 100 + A ), load SID and type

                H100 A

                SID will respond:

                + 010A   - 00F6   * 00000A00   / 0019 (0006)

The first value, 010A, is the sum. Use that value in the next command:

                H10A 1

                SID will respond:

                + 010B   - 0109   * 0000010A   / 010A (0000)

The second value, 0109, is the END value you want to use.


ADDITIONAL REFERENCES:  DR DOS 6 User Guide, Appendix D & FYI-M-1114