5_2.txt

This are the Laboratory programs for the 89c51

;;PULSE OF D=70% ON P1.0 USING INTERRUPT METHOD
ORG 0000H
SJMP MAIN 
ORG 000BH
SJMP ISR
ORG 0030H
MAIN:
MOV TL0,#044H
MOV TH0,#0FDH
SETB EA
SETB ET0
CLR P1.0
SETB TR0
ST:SJMP ST
ISR:
CLR TR0
JB P1.0,XXX
MOV TL0,#044H
MOV TH0,#0FDH
SJMP YYY
XXX:
MOV TL0,#0D4H
MOV TH0,#0FEH
YYY:
CPL P1.0
SETB TR0
RETI
END