Hello Erik (appologies for a spelling mistake in previous post)

Got it , may not be possible in my present hardware/flow but good to learn
but in that case the flow could be
to check for higher nibble and if it is different from 0xF store in variable
after timer expire again check for the same if both values are equal proceed
but where do we stop the cycling zeros for columns ? or how do we synchronize the lower nibble

If you can share any keypad.c file with me it”ll be nice to learn and adapt seeing the same

Regards,
Manish jain