In my project i want to interface a GSM modem and 24c02C i.e EEPROM (I2C based)to microcontroller. so now i am not understanding whether can i use same Rx-Tx pins to interface microcontroller (89s52) to EEPROM and GSM modem as well?? if not then is there any other microcontroller of AT89cxx/AT89sxx family with 2 serial ports? and which will support embedded c and assembly too!