My question is that once we get the value of 28,800 after dividing the crystal frequency (11.0592Hz) by 12 and then by 32, why we divide the value 0f 28,800 by a negative 3 (-3 = FD in HEX) in TH register for 9600. Why are we loading a negative value into TH? why not a positive value? I have studied the signed numbers and arithmetic instructions of 8051 in assembly but I dont know how the signed number concept apply over here. the question still remains why -3 for 9600. why not positive 3?