Re: debug and the newbe


"SpooK" <keith@xxxxxxxxxxx> a écrit dans le message de news:
1188322687.526706.115190@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On Aug 28, 12:29 pm, "Jean Pierre Daviau" <O...@xxxxxxxxxx>
wrote:
Hi everybody,

Please tell me whats wrong with that small dot com
----
-a 100
0DF1:0100 mov ah,09
0DF1:0102 mov dx, 107
0DF1:0105 int 21
0DF1:0107 "Allo"

Using that Interrupt function requires the string to be
terminated
with $. Also, it looks like your program will crash since there
is no
means to exit the program and the program flows directly into
the
data. Here is a more appropriate example, written in NASM.

ORG 0x100
[BITS 16]

;Print the String
mov ah,9
mov dx,MSG
int 0x21

;Exit to DOS
mov ax,0x4C00
int 0x21

;The Message to Print
MSG DB 'Allo$'

Assemble this example with NASM using the flat binary format
(-f bin)
and make sure it assembled file has the .com extension.

for sure this worked. Does it means I should use nasm already?
What is the meaning of 4C00 ?


But I was trying debug . . .
-a 100
0D65:0100 mov ax,9
0D65:0103 mov ax,120
0D65:0106 int 21
0D65:0108 mov ax, 4c00
0D65:010B int 21
0D65:010D int 20
f 010d 0119 90
-e 120 "Allo$"
-a 128
0D65:0120 jnz 108
0D65:0126 int 20
f 0126 0130 90

n huh.com
r ax:
60
w


.

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