I am working on p89v51rb2fn philips microcontroller , I programmed it and tested it , the second time I erased the chip and downloaded the same program it didn't work !! what could cause some thing like that ? please help it happened with me with 10 pcs !!! is their a probability that they got burned? I use Needham programmer , the application is Lift Control system and the board work with P87C51FA-4N (OTP) properly, even with p89v51rb2 it worked the first time properly but not after that