BrainDen.com - Brain Teasers
• 0

# LCD Watch

## Question

The LCD device shall tell the right time (HH:MM:SS) in 12-hour format..(see photo)
Figure out how can this watch be designed to work?

## Recommended Posts

• 0

For example you can encode MM using first digit except bottom segment (6^2=64>=60),

you just need to agree on some order or the above 6 display elements, so that they represent MM in binary.
(Each element of display is a binary digit "on"=1, "off"=0.)
Same way you can use second digit to encode seconds.
The remaining 4 elements of display (two bottom segments plus two dots) can be used to encode HH (4^2=16>=12).
I don't see any particular ordering that feels natural.

##### Share on other sites

• 0

You are missing some parameters in your problem. What do you mean by "how can this watch be designed to work?" Is it not already designed to work? Are you asking how an LCD device works?

##### Share on other sites

• 0

To display HH:MM:SS in 12-hour format you need ⌈log

2(12*60*60)⌉ = 16 bits of information, but your display has only 15 elements. Therefore the task is impossible if each element can only be "on" or "off". You need to cheat a little bit, for example add blinking or something like that.

Edit:

I miscounted the elements:) The display has 16 not 15 of them, so you

can use it without cheating.
Edited by witzar
##### Share on other sites

• 0

You are missing some parameters in your problem. What do you mean by "how can this watch be designed to work?" Is it not already designed to work? Are you asking how an LCD device works?

Reword: "is expected to" for "shall" tell the right time..

The device is a simple "level indicator"  that is to be converted to a watch.
You can replace the chip but retain the LCD screen.
How  would you design or program such chip?
##### Share on other sites

• 0

@witzar

How would you interpret the above photo to HH:MM:SS?

##### Share on other sites

• 0
Modifying witzar's (64,16,64) A _:_ A  system
to 0-:-0 for symmetry and progressive clockwork pattern..
Edited by TimeSpaceLightForce

## Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.