Number Ratio (Build 8086)

Question

Im trying to give a one-bit number and know the parity or parity of parity, for example, give 9 and print, which is an odd number.

This is what I have:

   assume cs:cseg,ds:dseg,ss:sseg
    cseg segment
    start:  
    mov ax, dseg
    mov ds, ax  

    mov ah, 01h ; Here, im adding a number
    int 21h 



    jp even
    jnp odd  

    even: 
    mov ah,09
    lea dx,par
    int 21h  
    jmp exit
    odd: 
    mov ah,09
    lea dx,odd1 
    int 21h   
    jmp salir
    salir:
    mov ax,4C00h
    int 21h

    cseg ends 

    dseg segment byte         
    even Db 'Even number$'
    odd11 Db 'Odd number$'
    dseg ends  

    sseg segment stack
    db 100h dup(?)
    sseg ends

end start

Thank! And sorry for my bad english.

Answer 1

To check if a number is odd or even , you check bit 0 of that number . if bit0 is set, then the number is odd. Nothing more. Do not confuse PF (parity flag) and JP / JNP conditions. The parity flag indicates that the number of bits set in the low value is equal to or odd.

From the documentation:

PF ( 2) - , 1 ; .

1 - , 00000001b PF , 2 - , 00000010b, PF ! 3 - , 00000011b, PF! ,

Answer 2

, , :

        test al,1
        jz even
odd:    ...
even:   ...

Answer 3

, , :

    mov     al, 09
    shr     al       ; shifts all bits right 1, lowest bit to carry flag
    jc      _odd     ; carry set - there was a bit in lowest position
_even:
    ; Do something with even numbers and exit
_odd:
    ; Do something with odd numbers and exit

. , "" , :

    mov    ah, 09
    xor    al, al    ; al = 0
_loop:
    shr    ah        ; lower bit into carry flag
    adc    al, 0     ; Add 0 + carry flag to al
    and    ah, ah    ; sets Z flag if ah is zero
    bne    _loop
    ;  al now contains the total number of bits contained in ah

Answer 4

!

Just add "and al, 00000001" above jp even

assume cs:cseg,ds:dseg,ss:sseg
    cseg segment
    start:  
    mov ax, dseg
    mov ds, ax  

    mov ah, 01h ; Here, im adding a number
    int 21h 

and al,00000001

    jp even
    jnp odd  

    even: 
    mov ah,09
    lea dx,par
    int 21h  
    jmp exit
    odd: 
    mov ah,09
    lea dx,odd1 
    int 21h   
    jmp salir
    salir:
    mov ax,4C00h
    int 21h

    cseg ends 

    dseg segment byte         
    even Db 'Even number$'
    odd11 Db 'Odd number$'
    dseg ends  

    sseg segment stack
    db 100h dup(?)
    sseg ends

end start

Answer 5

    .MODEL SMALL
 .STACK 100H

 .DATA
   PROMPT_1  DB  'Enter a number: $'
   PROMPT_2  DB  0DH,0AH,'The given number in binary is: $'
   PROMPT_3  DB  0DH,0AH,'$' 
   MSG1 DB 10,13,’Number is Odd $’
   MSG2 DB 10,13,’Number is Even $’

 .CODE
   MAIN PROC
     MOV AX, @DATA                
     MOV DS, AX

     LEA DX, PROMPT_1                
     MOV AH, 9
     INT 21H

     XOR BL, BL                  
     MOV CX, 8                   
     MOV AH, 1                   

     @INPUT:                     
       INT 21H                   
       CMP AL, 0DH                
       JE @END                   
       AND AL, 0FH                
       SHL BL, 4                 
       OR BL, AL                  
     LOOP @INPUT                  

     @END:                        

     MOV AL, BL                   
     MOV CX, 8                    

     @LOOP:                       
       SHR AL, 1                  
       RCL BL, 0                  
     LOOP @LOOP                   

     LEA DX, PROMPT_2             
     MOV AH, 9
     INT 21H

     MOV CX, 8                    
     MOV AH, 2                    

     @OUTPUT:                     
       SHL BL, 1                  

       JNC @ZERO                  
         MOV DL, 31H              
         JMP @DISPLAY             

       @ZERO:                     
         MOV DL, 30H              

       @DISPLAY:                  
         INT 21H                  
     LOOP @OUTPUT                      



MOV AH,01H
INT 21H 

mov ah,01h


SAR AL,01h
JC ODD


LEA SI,MSG1
CALL PRINT

JMP TERMINATE

ODD:
LEA SI,MSG2
CALL PRINT


TERMINATE:
MOV AH,4CH
INT 21H

PRINT PROC
MOV DX,SI
MOV AH,09H
INT 21H




     MOV AH, 4CH                 
     INT 21H

 END MAIN