;PROGRAM NAME:INTR7.ASM
;TEST SERIAL INTERRUPT
;
COUNT   EQU     9217    ;10mS FOR XTAL=11.0592MHz
;
DIGIT1  REG     P1.4
DIGIT2  REG     P1.5
LED     REG     P3.7
;
DISP    EQU     30H
SEC     EQU     31H
I_CNT   EQU     32H
;
O_TRUE  REG     20H.0
;
        ORG     0000H
        LJMP    RESET
        ORG     0003H           ;INT0 INTERRUPT
        RETI
        ORG     000BH           ;TIMER0 INTERRUPT
        LJMP    INT_TIMER0
        ORG     0013H           ;INT1 INTERRUPT
        RETI
        ORG     001BH           ;TIMER1 INTERRUPT
        RETI
        ORG     0023H           ;SERIAL INTERRUPT
        LJMP    SERIAL
;
RESET   MOV     R0,#00H
        DJNZ    R0,$    ;WAIT
        MOV     DISP,#00H       ;DISPLAY '0''0'
        MOV     SEC,#00H
        MOV     SP,#40H
;
        MOV     A,#00100001B
        MOV     TMOD,A
;TIMER0 IN MODE 1:16-BIT COUNT
        MOV     TH0,#(65536-COUNT)/256
        MOV     TL0,#(65536-COUNT).MOD.256
        CLR     TF0     ;CLEAR TF0
        SETB    TR0
;
;TIMER1 IN MODE 2:8-BIT AUTO RELOAD MODE
        MOV     TH1,#FDH
        SETB    TR1     ;TIMER1 START
;
        MOV     SCON,#01000000B
        SETB    REN     ;RECEIVE ENABLE
;
;TIMER0 SETTING
        SETB    PT0
        SETB    ET0     ;ENABLE TIMER0 INTURRUPT
;
        CLR     RI
        CLR     TI
        SETB    ES      ;ENABLE SERIAL INTERRUPT
;
        SETB    EA      ;ENABLE SYSTEM INTERRUPT
;
LOOP    LCALL   LDELAY
        LCALL   LDELAY
        SJMP    LOOP    ;WAITTING
;
;
SERIAL  JNB     RI,NO_DATA
        CLR     RI
        MOV     A,SBUF
        CJNE    A,#100,$NEXT
$NEXT   JNC     NO_DATA
        MOV     DISP,A  ;DISPLAY A NEW VALUE
NO_DATA RETI
;
;TF0=1
INT_TIMER0
        CLR     TF0     ;CLEAR TF0
        MOV     TH0,#(65536-COUNT)/256
        MOV     TL0,#(65536-COUNT).MOD.256
        INC     SEC             ;SEC=SEC+1
        MOV     A,SEC           ;CHECK SEC>=100?
        CJNE    A,#100,$CHK1    ;A-100
$CHK1   JC      $NEXT
        MOV     SEC,#00H        ;SEC=0
;
$NEXT   MOV     A,SEC
        CJNE    A,#40,$CHK2
$CHK2   JNC     OVER
        SETB    LED             ;LED ON
        SJMP    DISPLAY
OVER    CLR     LED
;
DISPLAY MOV     A,DISP
        ANL     A,#00001111B    ;GET LOW NIBBLES
        SETB    ACC.5           ;BIT5,BIT4=10
        MOV     P1,A
        ACALL   DELAY
;ADD EXTRA PART
        CLR     P1.4
        CLR     P1.5
        ACALL   DELAY
;
        MOV     A,DISP
        SWAP    A
        ANL     A,#00001111B
        SETB    ACC.4           ;BIT5,BIT4=01
        MOV     P1,A
        ACALL   DELAY
        CLR     P1.4
        CLR     P1.5
        RETI
;
DELAY   MOV     R7,#80H
        DJNZ    R7,$
        RET
;
LDELAY  MOV     R1,#00H
$R0     MOV     R0,#00H
        DJNZ    R0,$
        DJNZ    R1,$R0
        RET