LED Countdown Timer with AT89C2051

Posted on Feb 5, 2013

A simple count-down LED timer that counts in minutes and seconds. Three buttons below the LED provide control of the unit, allowing you set the desired countdown time in minutes and seconds and a start/stop button. Completion of the countdown is indicated by an alarm that starts when the countdown has finished and the display reads zero.

LED Countdown Timer with AT89C2051
Click here to download the full size of the above Circuit.

The alarm is stopped by pressing the start/stop button. Counts down from up to 99 minutes 59 seconds Loud buzzer

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