I don't use DS80C320 but I think I know, what the problem is. Timers in DS80C320 can count in 8032 compatible mode (one increment every 12 clock cycles) or in fast mode (one increment every 4 clock cycles). So there must be a problem with the baud rate setting and you cannot establish an RS232 connection with your PC. You should modify the code to initialze baud rate timer properly to count in 8032 compatible mode.