Hi,

You use Timer2 for setting but you use overflow flag of Timer0. Make the changes like below it'll work.

Regards,
George


org 2000h ; 1 Minute Program
minute: CLR P1.7
Min1: clr tr0
MOV TCON,#00010010B
MOV TMOD,#00000010B
MOV TL0,#3CH
MOV TH0,#00H
SETB TR0
Time2: MOV R1,#25
Time1: MOV R0,#160
Time: JNB TF0,Time
CLR TF0
MOV TL0,#3CH
MOV TH0,#00H
DJNZ R0,Time
DJNZ R1,Time1
CPL P1.7
JMP Min1
END