gooda

ORG 0
JMP START
ORG 03H
JMP ISR0
ORG 13H
JMP ISR1

START: MOV IE,#10000101B
MOV IP,#00000100B
CLR IT0
SETB IT1

MAIN: NOP
JMP MAIN

ISR0: PUSH A
PUSH PSW
CLR RSL
SETB RS0

MOV P0,#00001111B
CALL DELAY
MOV P0,#00000000B
CALL DELAY

MOV P0,#00001111B
CALL DELAY
MOV P0,#00000000B
CALL DELAY

POP PSW
POP A
RET1

ISR1: PUSH A
PUSH PSW
CLR RS0
SETB RSL

MOV P0,#00001111B
CALL DELAY
MOV P0,#00000000B
CALL DELAY

MOV P0,#00001111B
CALL DELAY
MOV P0,#00000000B
CALL DELAY

POP PSW
POP A


DELAY: MOV R0,#200
D1: MOV R1,#100
D2: DJNZ R1,D2
DJNZ R0,D1

RET

END