design a digital clock

bertus

Joined Apr 5, 2008
20,773
Hello,

You just hyjacked an existing thread with a completely different subject:
Landline control?

As we do not allow this, I created a new thread for you.

Bertus

@crutshow,
When you see a hyjack, report the post and do not reply to the hyjacker.
 

absf

Joined Dec 29, 2010
1,948
همسات;733253 said:
Hello can you help me plase
Basic and I needed to design a digital clock
What kind of digital clock do you want? One made from discrete logic gates or one using MCU? How many digits do you need? Output go to LED or LCD?

If you check the completed projects section, I am sure you can find a few.


Allen
 

absf

Joined Dec 29, 2010
1,948
I think what ak meant was why build a digital clock when you can buy it cheaply from chinese-goods shops like wall-mart or Daiso.

If the purpose is to learn electronics, then more details have to be given before we can render any appropriate help.

Allen
 

AnalogKid

Joined Aug 1, 2013
8,608
Well, you're 0 for 2, but I appreciate the effort. What ak meant was why are you designing a digital clock? Not why design rather than build; that question was decided before the OP. What are the requirements, the environment, the parameters that determine the nature of the design?

All of the questions are 'why'.

ak

And - There is a quantity of time that can not be sub-divided. Physical reality has a lower limit on a tick. Because of the quantum nature of existence, all clocks are digital.
 

djsfantasi

Joined Apr 11, 2010
6,838
Does that include candle clocks, water clocks, and sundials?
IMHO,
Candle clocks -> digital
Water clocks -> digital
Sundial -> analog

The first two are based on the molecular behavior of their respective substances and thus discrete/digital events. Unless one were to argue the particle theory of light, I see a sundial as an analog device.

:)
 

AnalogKid

Joined Aug 1, 2013
8,608
The particle theory of light is easy. It's the quantum theory of existence that is counter-intuitive.

A quanta of mass - easy.
A quanta of energy - ok, that takes a bit more imagination.
A quanta of time - ?!?!?

ak
 

Treeman

Joined May 22, 2014
157
IMHO,
Candle clocks -> digital
Water clocks -> digital
Sundial -> analog

The first two are based on the molecular behavior of their respective substances and thus discrete/digital events. Unless one were to argue the particle theory of light, I see a sundial as an analog device.

:)
if you use ur finger as a sundial does that make it digital?

must be bed time
 

#12

Joined Nov 30, 2010
18,210
Four days later and no response from a one time poster. I'm beginning to doubt this will end up as a clock.
 

sirch2

Joined Jan 21, 2013
1,026
Depends a bit on what you take analog to mean. Taken as a continuously varying signal, i.e. non-quantized then all spring and pendulum driven mechanical clocks are digital because they use an escapement to regulate the motion, hence the ticking.

If you take analog to mean "analogous" i.e. corresponding in some way to something else, then any clock with a moving indicator that is analogous to the motion of the earth around the sun is analog.

On the other hand you could just accept the standard definition in relation to clocks that something with hands is analog and something with changing digits is digital. :rolleyes: Words are assigned new and additional meanings as we move on - after all literally does not literally mean literally anymore http://www.theguardian.com/commentisfree/2013/aug/13/literally-broken-english-language-definition
 

AnalogKid

Joined Aug 1, 2013
8,608
Depends a bit on what you take analog to mean. Taken as a continuously varying signal, i.e. non-quantized then all spring and pendulum driven mechanical clocks are digital because they use an escapement to regulate the motion, hence the ticking.
Interesting point. A pendulum is sinusoidal, or at least non-discontinuous oscillators, but the escapement is a comparator.

I think the general use is that an analog display (time, volts, whatever) indicates quantity by physical movement (continuous or piecewise) of an indicator against a quantified background, compared to a digital display that displays digits with a descriptor. People gain information from an analog display not just by looking at the numbers being pointed to. Research shows that people tell time with an analog display by seeing distances and areas, not numbers. So an LED bar graph would qualify as analog for the same reason as a ticking clock face. Functionally, both are much closer to their original incarnations (VU meter and synchronous motor clock) than their digital counterparts.

ak
 

Merlin3189

Joined Oct 20, 2013
7
Originally Posted by AnalogKid &ErnieM
There is a quantity of time that can not be sub-divided. Physical reality has a lower limit on a tick. Because of the quantum nature of existence, all clocks are digital."
"Does that include candle clocks, water clocks, and sundials?"

Since this is the General Chat area, I suppose we can ramble off into fantasy.
So where does this "quantum nature of existence" come from?
As far as I know, there is a quantum mathematical model about energy, but a quantum theory of "existence" (whatever that may mean) and time must have passed me by. Any references to explanation of that? (My first look in WikiP brought "While time is a continuous quantity in both standard quantum mechanics and general relativity, many physicists have suggested that a discrete model of time might work."

But looking the second point, presumably a water clock or candle ultimately changes by one molecule at a time, limiting its resolution, but not saying anything about the nature of the quantity it is measuring.
The sundial is a more difficult question (for me), but I'd say quantum time people would have to come up with an interesting story about that. I guess you might see the ultimate resolution of a sundial when you were so far from the sun that it looked like a point source and you had a gnomon not much thicker than the wavelength of light (which one from the Sun's mixed output?) whose shadow was a diffraction pattern (the most un-quantum like part of light's nature.)
I may be looking at that from the wrong end, since the shadow movement is produced not by the Sun, which is simply the supposedly fixed reference, but by the movement of the Earth. Does the Earth rotate in quantum jumps? Or is its angular momentum quantised so that (unless it gains or loses momentum or mass) it must rotate at an absolutely fixed rate?

PS. As far as I am concerned, a digital clock is one which can only SHOW the time in discrete steps as opposed to an analogue display which shows time continuosly (accurately or otherwise.) Before the advent of electronic digital timepieces there were plenty of digital clocks driven by exactly the same mechanism as analogue clocks (coiled spring, gears & escapement, or synchronous electric motor were common.)
I don't know whether there are analogue clocks based on quartz crystals, divided down by digital IC to drive a synchronous motor, but I'd be surprised if there werent.

I even had a "digital" Voltmeter whose display was a set of rotating drums with 10 digits mounted on galvanometers! (I don't know the details of its operation, but it was obviously designed before IC days and contained lots of Ge transistors.)
 
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