I am using 8051. I had been trying with my switch which i seen is perfectly right.
The problem is whenever it count back to the reset and starts incrementing the value seemed to be distorted. Please help me. My project is up to due.
ORG 0000H
JMP MAIN
ORG 100H
MSG EQU 300H ; STARTING ADDRESS OF THE MESSAGE
MSGT EQU 310H
MAIN: CLR P2.5 ; SEND COMMAND MODE
CLR P2.6 ; WRITE
MOV A,#38H ; FONT
cALL STROBE
MOV A,#0CH ; CURSOR OFF
CALL STROBE
MOV A,#06H ; DISPLAY PATTERN
CALL STROBE
MOV A,#02H ; CLEAR DISPLAY
CALL STROBE
MOV A,#01H ; RETURN HOME
CALL STROBE

SETB P2.5 ;DATA MODE (WORD FOR 'TIME')
BACK1: MOV DPTR,#MSG
CALL DISPLAY
CLR P2.5 ;COMMAND MODE
CLR P2.6
MOV A,#CFH ;POSITION AT SECOND LINE
CALL STROBE

;-----------------------------------------------------

MOV P1,#0FFH

;-----------------------------------------------------

SETB P2.5 ;DATA MODE (FOR 00:00)
BACK: MOV DPTR,#MSGT
CALL DISPLAY
CALL MOVECL
;-----------------------------------------------------
MOV R2,#10H

;-----------------------------------------------------

CHECK0: JNB P1.0,CHECK0 ;CHECK BIT IS NOT SET ( HOLD HERE TILL CHANGES)

;-----------------------------------------------------

MOV R6,#30H
MOV R5,#30H
S10: MOV R7,#30H ;R7 USED FOR TENTH SECOND ONLY
CSI0: INC R7
MOV A,R7 ;COPY THE CURRENT VALUE OF R7 TO A
CALL STROBE

;-----------------------------------------------------

CHECK1: JNB P1.0,CHECK5 ;CHECK BIT IS NOT SET(HOLD HERE TILL CHANGES)
IF: CJNE R2,#20H,HERE
JB P1.0,BACK1

;-----------------------------------------------------
HERE: CALL MOVECL
CJNE R7,#39H,CSI0
MOV R7,#30H
MOV A,R7
CALL STROBE
CALL MOVECL
JMP S10

CHECK5: MOV R2,#20H
CHECK4 JNB P1.0, CHECK4
RET
SHIFT4R:CALL MOVECR ;MOVE CURSOR RIGHT BY 4
SHIFT3R:CALL MOVECR ;MOVE CURSOR RIGHT BY 3
SHIFT2R:CALL MOVECR ;MOVE CURSOR RIGHT BY 2
SHIFTR: CALL MOVECR ;MOVE CURSOR RIGHT BY 1
JMP S10

;THIS MIGHT HAVE SOME CHANGES OR DELETE IF IT NOT APPLICABLE TO ANY USE
SHIFT4L:CALL MOVECL ;MOVE CURSOR RIGHT BY 4
SHIFT3L:CALL MOVECL ;MOVE CURSOR RIGHT BY 3
SHIFT2L:CALL MOVECL ;MOVE CURSOR RIGHT BY 2
SHIFTL: CALL MOVECL ;MOVE CURSOR RIGHT BY 1
JMP S10

MOVECR: CLR P2.5 ;MOVE CURSOR TO THE RIGHT
CLR P2.6
MOV A,#14H
CALL STROBE
SETB P2.5
RET

MOVECL: CLR P2.5 ;MOVE CURSOR TO THE LEFT
CLR P2.6
MOV A,#10H
CALL STROBE
SETB P2.5
RET

DISPLAY:CLR A ;DISPLAY FOR 'TIME' AND '00:00'
MOVC A,@A+DPTR
ANL A,#01111111B
CJNE A,#0DH,LOOP
RET
LOOP: CALL STROBE
INC DPTR
JMP DISPLAY

STROBE: SETB P2.7 ;SEND TO THE SCREEN
MOV P0,A
CALL DELAY
CLR P2.7
RET

DELAY: MOV R0,#0FFH
AA: MOV R1,#0FFH
BB: DJNZ R1,BB
DJNZ R0,AA
RET

ORG 300H
DB 'TIME :',0DH
ORG 310H
DB '00:00',0DH