hello,

i've made program to generate odd & even parity from given bunch of data(but here i've taken only for hex numbers for ex)..
but it's not working...

    ORG 00H
    COUNT EQU 2                        ;totel hex size/2 (IN DESIMAL)
    DB 11H
    DB 00H
    DB 33H
    DB 22H                ;data

    MOV A,#00H                        ;acc initialization
    MOV DPTR,#0000H                      ;dptr loaded with even data address
    MOV R1,COUNT                    ;counter
    CALL LOOP1
    MOV R3,A                         ;even parity
    MOV A,#00H                            ;acc initialization
    MOV DPTR,#0001H                     ;dptr loaded with odd data address
    MOV R1,COUNT                       ;counter
    CALL LOOP1
    MOV R4,A                         ;odd parity

LOOP1:
LOOP: MOV A,#00H
      MOVC A,@A+DPTR
      ADD A,R2
      MOV R2,A
      INC DPTR
      CLR C
      DJNZ R1,LOOP
      RET

END

i'm using keil 4 for debugging..

when try to debug it sticks at 0000h location ...

thanks in advance...

 

You haven't setup any stack pointer prior to using the CALL/RET instruction and your program execution falls through to the LOOP subroutine code.

    MOV DPTR,#0001H                     ;dptr loaded with odd data address
    MOV R1,COUNT                       ;counter
    CALL LOOP1
    MOV R4,A                         ;odd parity

        ;<<<--- what instruction to execute next ????
  
LOOP1:
LOOP: MOV A,#00H
      MOVC A,@A+DPTR
      ADD A,R2
      MOV R2,A
      INC DPTR
      CLR C
      DJNZ R1,LOOP
      RET