At the moment I do not have a kitchen timer. Not because I do not want one, (they’re cheap enough to buy) but because it seems impossible to buy a kitchen timer with a decent user interface.
That means I have to build my own, which I just the kind of stuff I like. The user interface is probably going to look like the picture. Using this timer is extremely simple: If you need an count down time of for example 7 minutes then all you have to do is press the “down” button for the units of the minutes 3 times and then press “Start/Add” and the countdown will start.
For more detail: Kitchen Timer using ATTiny2313 microcontroller