Hello, I am using AT89C51RD2 as a target processor operates on 11.0592MHz crystal oscillator. In my application I get command through serial port.It supports two checksum alogorithms one is standard CRC16 and another is Prop.Checksum but in the command it is not mentioned which CRC is in this command hence I have to do calculation of which CRC is this.For this calculation it takes more time than required. Can you please tell me how to increase the execution speed? Also how to bring uc in X2 mode by keeping same baudrate and timer tick?