hello there
how are we going to use delay() in the code if keypad seem unresponsive if we have delay in the code?
from Arduino Playground - KeypadTutorial
'Consider, though, when you are writing your code that every delay() you use will take processing time away from the keypad. Something as short as delay(250) can make the keypad seem very unresponsive. And the same thing will happen if you sprinkle a bunch of delay(10)'s all through your code'
how are we going to use delay() in the code if keypad seem unresponsive if we have delay in the code?
Don't use delay()
You need to look into using millis() for timing as in the BlinkWithoutDelay example and Several things at the same time
Save the time an event happens then each time through loop() check whether the required period has elapsed since the event. If not then go round loop() again reading inputs etc. If the period has elapsed then take the required action.