Very simple countdown timer with 7 segment displays

This is very simple countdown timer implemented on 89C2051 microcontroller. One button is used to set time up to 99 seconds, another is for starting timer. Time is displayed on two 7 segment LED displays.



Buttons and display scanning share same pins so algorithm has to check buttons and display time on LED displays in a row sequence. Source code is included that allows yo modify program and compile.

[..Source link..]

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  2. how can i make this, i need to make it for school but i can’t find it elswhere on the internet can somebody explain it to me. i need a countdown from 60 seconds to 0 seconds.

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