When I pressed the switch i can't get any O/P from the keypad(apart from program in controller,checked with multimeter also).
Is this circuit is correct or have to make any change in this circuit..?
It looks like when you press any key, it shorts all of the RB inputs to ground. All of the 3,4 pins of the switches are connected together.
The switches need to be wired in an x-y matrix so that an x line is connected to one side of the switch and a y to the other. Pressing a
switch connects an x to a y. An x line would be an output and a y line an input.