...I am still in big trouble If I don't solve this problem. I have put the same 89c51 in a training board of mine and it works correctly (i.e. ATMEL FLIP, the in system programmer can connect succesfully to the micro). Hence a problem exists, in my custom project mainboard,and it's hardware wise, I'm just not seeing it, and THATS the problem.

Guys any sugestions? I really don't know what to do further. My tiny brain tells me that if the Max232 is working well, crystal frequency is ok, rst and psen logic levels are correct, and ea is tied high than presto eveything should work, but it isn't!! I'm starting to think I'd better start my project write-up and forget the bloody hardware issues. At least I'd have a chance of passing.