
Microprocessor Lab
Experiment No. (1)
DEBUG Commands
Objective:-
To learn how to use MS-DOS prompt and DEBUG commands.
Equipments:-
PC
Theoretical Background:-
List of Debug Commands:-
Function
Syntax
Example
Assemble
A [address]
A 100
Compare
C range address
C 140 148 340
Dump
D [range]
D D [address] [L length]
D 100 130
D 200 L 5
D 138d:10
Enter
E address [list]
E 100 d2
E 100 ‘hello’
Fill
F range list
F 100 110 ff
F 100 110 ‘X’
Go
G [=address] [addresses]
G = 104 114 11f
Hex
H value1 value2
H 333 111 results
444,222
Input
I port
I 378
Load
L [address] [drive] [first sector]
[number]
L 100 2 0 1
Move
M range address
M 100 11f 200
Name
N [pathname] [arg list]
N c:\temp\doswinok.com
Output
O port byte
O 378 ff
Proceed
P [=address] [number]
P = 205 7
Quit
Q . . . . . . . . . (Learn this
first!)
Q
Register R [register]
R BX
Search
S range list
S 200 210 ff
Trace
T [=address] [number]
T = 205 7
Unassemble U [range]
U 100 108
Write
W [address] [drive] [first sector]
[number]
W 5

Procedure:-
1.
Open a DOS window by double clicking the DOSBOX icon.
2.
Enter the following Command:
Z:\ > MOUNT C C:\8086 <ENTER>
Z:\ > C: <ENTER>
3.
Load DEBUG as follows:
C:\ > DEBUG <ENTER>
-
-
4.
Run the following commands at the DEBUG and write the results
:
-R <ENTER>
-R ax<ENTER>
-Type 1234<ENTER>
-R ax<ENTER>
-RF<ENTER>
-Type ov dn<ENTER>
-RF<ENTER>
-D 0200 L 1<ENTER>
-E 0200 ff <ENTER>
-D 0200 L 1<ENTER>
-E 0100 'test'<ENTER>
-D 0100 <ENTER>
-F
0100 010f
ff<ENTER>
-D
0100 010f<ENTER>
-F 0100 010f ‘microprocessor’<ENTER>
-D 0100 010f<ENTER>
-C 0200 0210 0400<ENTER>
-F 0400 0410 D0<ENTER>
-S 0400 0410 D0<ENTER>
-S 0400 0410 DF<ENTER>
-Q <ENTER>
5.
C:\ > Exit <ENTER>

Lab work:
Apply each of the following command, using the suitable Debug command
then write your answer on a paper.
1. Display the contents of SP, BP,SI , DI registers.
2. Change the value of DS to FFFF, CS to AAAA.
3. Change the value of the Flags to the opposite values.
4.
Fill the contents of the memory A3F0:0000 0010 with BB
.
5. Search for the value BB in the memory A3F0:0000 0010
6. Add and Subtract 222 ,888
7. Fill the contents of the memory B800:0000 0020 with ‘X’ now look at your
DOS screen.