Hi.
I am using AT89C51ED2 in PDIP 40 package. The problem is that the P3^7 does not change its state and always remain Cleared. I've written a code that works fine with the simulator but it does not work in the Microcontroller. I am using Keil version 7.07a. My controller connects with a chip's Enable pin. I removed that chip but found pin low. Kindly consider the following points:
1. Do I need to configure any registers for this purpose?
2. I am using Flip for programming my Controller. Do I need to program it using Hardware level programming instead of Bootloader programmer, for the first time.
3. Is this problem concerned with the built-in XRAM or XEEPROM of the Controller?
4. Is there anything to configure all Ports?
5. Is this problem related with ALE.
6. Is the problem related with PDIP package, since I'd used the PLCC44 package, it seem working fine to me.
7. I'd defined all my ports in same manner, but port 3^7 always remain low.

Please help me out. This problem is wasting too much of my time.

Regards.

Maaz Qazi