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Hard LCD Watch Time Puzzle

Hard LCD Watch Time Puzzle - 8 January

The LCD device should be able to tell the right time in the format HH:MM:SS in 12-hour format. You can refer to the picture to get an idea.

The device is a simple "level indicator" which has to be converted into a watch. How will you program it to work?

For Solution : Click Here


  1. The first digit except bottom segment can encode MM (6^2=64>=60).
    Some order is needed to be agreed upon so that they represent the MM in binary.
    Each element of display is a binary digit:

    In the same manner you can encode seconds by using the second digit.

    The rest four elements of display (two bottom segments and two dots) can be used to encode HH (4^2=16>=12)