Hi Ram,

Your scheme seems to be OK and it should connect to FM.

I have been using the 40Pin DIP version of P89V51RD2 with a 11.092MHz for more than two years now. And it is a drop in replacement for the P89C51RD2.

All I do is this :

- Pull up the PSEN via a 10K to VDD. ( Not required but the PCB was designed for P89C51RD2)
- Select "Assert DTR and RTS while Com port open" in FM.
- Enter other relevant fields in the FM.

And it connects without complaint. Maybe you have a dud MCU or your Reset generator is not producing clean reset pulses. I use the DS1232. Or you have looooong RS232 cable...

And finally though stating the obvious, please ensure this :

Actually there is a whole lot of confusion on these pins TxD and RxD ! Male , Female, 9-pin, 25-pin, DCE , DTE etc etc. The only thing I now know is that after linking the MCU to the PC com port, I should read around -8V on both pins 2 and 3 with respect to 5. And use a 'regular' RS232 cable.(not the null modem). I know it sounds rather basic, but most problems have basic origins !

Raghu