Deepak Kash wrote:
-------------------------------

As far as my limited knowledge of 51 prog goes if you need accurate timing use assembly and a 12mhz crystal

Absolutely NOT, please read the tutorial on timers: http://www.8052.com/tuttimer.phtml

Accuracy of timing has nothing to do with the crystal frequency. The accuracy of your timing is directly related to the stability of your crystal...



send data to PC using at 2400 bps connectivity

Why 2400 bps? Change to an 11.059 MHz crystal and you should be OK for 1200, 2400, 4800, 9600, 14400, 19200, 28800 bps or 57600 bps see http://www.keil.com/c51/baudrate.asp

regards
Patrick