; designed by Engr. Tarique R. Memon
;electronixforu.com 
; counter counts upto 99 on 7 seg display
; dated 18-12-2009 Friday, 2:19 PM


 ORG  00
;******************************LOCATION INITIALIZING
SEG EQU P0

LOC1 EQU 41h
LOC2 EQU 42h
LOC3 EQU 43h
LOC4 EQU 44h

;**************TEMPERAROY LOCATION*******************

TLOC1 EQU 45h
TLOC2 EQU 46h
TLOC3 EQU 47h
TLOC4 EQU 48h
;******************BIT SETTING FOR 7 SEG***********
DISP1 BIT P2.4
DISP2 BIT P2.5

;******************SENDING 0 to last digit***********
mov LOC2, #0C0h
;**********************MAIN\BODY PROG**********************
MOV TLOC1, #00 
REST:  
   MOV DPTR, #DATA
START:  CLR A
   MOVC A,@A+DPTR
   cjne a, #00H, new
   SJMP REST1
new:  ACALL LAMP1
   ACALL DISPLAY
   INC DPTR
   SJMP START
REST1:  MOV DPTR, #DATA
   CLR A
   ACALL RETURN
   INC A
   CJNE A, #0AH, CONTINUE
   MOV TLOC1, #00H
   MOV LOC2, #0C0H
   SJMP REST
CONTINUE: ACALL GET
   MOVC A,@A+DPTR
   ACALL LAMP2  
   SJMP REST  
DATA: DB 0C0h,0F9h,0A4h,0B0h,99h,92h,82h,0F8h,80h,90h,00h
LAMP1:  MOV LOC1, A
RET
LAMP2:  MOV LOC2, A
RET
RETURN: MOV A, TLOC1
  RET
GET: MOV TLOC1, A
RET

;******************Displays ON***************************

DISPLAY: MOV R0, #128

LOOP: acall DIGIT1
  acall DIGIT2
    DJNZ R0, LOOP
  RET
;********************DIGIT CONTROL***********************  
DIGIT1: SETB DISP1
  MOV SEG, LOC1
  ACALL DELON
  CLR DISP1
  ACALL DELOF
  RET
DIGIT2: SETB DISP2
  MOV SEG, LOC2
  ACALL DELON
  CLR DISP2
  ACALL DELOF
  RET

DELON:
        MOV     R1,#0AH
AGA:    MOV     R2,#0FFH
        DJNZ    R2,$
        DJNZ    R1,AGA 
     RET  

DELOF:

AGA1:   MOV     R2,#07H
        DJNZ    R2,$

        RET