sorting 32 bit numbers in 8086 - sorting

Question

i wrote this code and think for it about 5 hours;
However i stuck in sorting part:
its begin to loop and never stop !
where did i wrong ???
IT SEEMS that the array didnt get the numbers correctly.
can any one help please ?
page 110,100
Title 'decimal sorting'
Data_here segment
A DD Dup 20(?)
msg1 DB 'Enter a maximum 6 digits number : ',0DH,0AH,'$'
msg2 DB 0DH,0AH,'The sorted results are : ',0DH,0AH,'$'
Data_here Ends
Stack_here segment
DW 10 DUP(?)
Stack_here Ends
Code_here segment
Assume CS:code_here , DS:Data_here ,SS:Stack_here
Main Proc near
mov AX,Data_here
mov DS,AX
mov AX,Stack_here
mov SS,AX
Call decimal_input
call sorting
call decimal_output
mov AH,4CH
int 21H
main Endp
decimal_input proc near
PUSH A
mov AH,09H
Lea DX,msg1
int 21H
mov CH,20
next_number:
mov BH,6
mov DX,0
mov si,4
next_digit:
mov AH,07H
int 21H
CMP AL,0DH
JNE check_digit
CMP BH,6
JE next_digit
DEC CH
JZ end
mov DX,0DH
mov AH,02H
int 21H
mov DX,0AH
Int 21H
jmp next_number
check_digit:
cmp AL,30H
JB next_digit
cmp AL,39H
JA next_digit
mov AH,02H
mov DL,AL
int 21H
SUB AL,30H
SHL DX,4
ADD DL,AL
DEC SI
JZ save
DEC BH
JNZ next_digit
jmp remain
save:
mov A[DI],DX
SHL A[DI],8
add si,4
DEC BH
jmp next_digit
remain:
ADD byte ptr A[DI],DL
mov DX,0DH
mov AH,02H
int 21H
mov DX,0AH
INT 21H
INC DI
DEC CH
JNZ next_number
end:
pop A
RET
decimal_input ENDp
sorting proc near
Push A
mov SI,DI
check:
mov AX,word ptr A[SI]
mov BX,word ptr A[DI+2]
CMP AX,BX
JA change
JE extra_check
add SI,2
continue:
add DI,2
CMP DI,38
JA finish
JB check
extra_check:
mov CX,word ptr A[DI+1]
mov DX,word ptr A[DI+3]
cmp CX,DX
JNA continue
mov word ptr A[DI+1],DX
mov word ptr A[DI+3],CX
jmp continue
change:
xchg AX,BX
mov CX,word ptr A[DI+1]
mov DX,word ptr A[DI+3]
xchg CX,DX
mov word ptr A[DI],AX
mov word ptr A[DI+1],CX
mov word ptr A[DI+2],BX
mov word ptr A[DI+3],DX
jmp continue
finish:
Add sp,2
cmp Sp,40
JE ending
mov DI,SP
jmp check
ending:
POP A
RET
sorting ENDP
decimal_output proc near
PUSH A
mov AH,09H
lea DX,msg2
INT 21H
next_no:
mov DL,0
mov AL,0
mov AH,0
next:
CMP AL,0
JE next1
mov DL,byte ptr A[DI]
ADD DL,30H
mov AL,1
int 21H
next1:
inc DI
inc AH
cmp AH,8
JB next
CMP DI,80
JA THE_END
mov DX,0DH
mov AH,02H
int 21H
mov DX,0AH
int 21H
jmp next_no
THE_END:
pop A
RET
decimal_output ENDp
code_here Ends
END MAIN

Answer 1

I think your problem might be here
Add sp,2
cmp Sp,40
You are using sp as a loop counter, but you never initialize it. Additionaly I also don't understand why you are using sp in the first place. Of course it is theoretically possible, but then you would have to restore it before you return. When your proc returns it will screw up, because the stack pointer is corrupted. So you shouild use some other register or a memory variable (bp is not used in your code).
And I would strongly recommend to reformat your code, to make it more readable (when I looked at it I formatted it like this which makes it better readable):
sorting proc near
Push A
mov SI,DI
check:
mov AX,word ptr A[SI]
mov BX,word ptr A[DI+2]
CMP AX,BX
JA change
JE extra_check
add SI,2
continue:
add DI,2
CMP DI,38
JA finish
JB check
...