i want the circuit diagram for 4*4 keypad interfacing with P89V51RD2 for my project.
if the LCD is showing results without pressing any key on key board???
2) check out if there is any short connection that might causing you that problem..
4) have you pressed any key and check weather it is showing that key on LCD or not????
keypad is connected with PO..
PO needs PULL UP resistor ..
use 10K pull up resistor and ur problem will be solved.
i already posted a diagram named CODE LOCK..
you can see that diagram , hope it will solve ur problem .,.