//晶振12M DSEG AT 30H timetemp: DS 1 LED: DS 1 CSEG AT 00H ORG 0000H LJMP START ORG 000BH LJMP Timer0Interrupt START:MOV SP,#60H MOV timetemp,#20 MOV P1，#0FFH;LED低电平点亮 LCALL InitTimer0 MOV LED,#0FEH LOOP:MOV P1,LED ;add your code here!