DIGITAL CLOCK HARDWARE DESIGN (PLS CORRECT AND PLS HELP)

[Jay Duluguin]

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Pls correct the design and make some additional design for the setting of time just like in digital watches. Loacte where the setting mode could be placed. This means we can set the correct time e.g., SECONDS, HOURS, or DAYS OF WEEK.

GUIDE US ACCORDINGLY!!!!!!!

j_f_duluguin@yahoo.com

 

[patroclus]

In fact, I made a digital clock almost identical of yours a few months ago. It works fine, but I got the seconds pulse from a crystal oscillator. Also, you don't need logic gates to reset the hours counter, just use 7490's reset inputs. (hours units Q2 and hours tens Q1 each one into one of resets inputs of 7490 hours tens and units).

Hope it helps.

 

[Jay Duluguin]

digital clock hardware design

Thanks for the reply patroclus.

The design is to automatically reset and preset when the clock reach after 12:59:59 and at the start of power supply.In other words, the clock must sense the 13:00:00 to reset and preset immediately before it is display. and since the only way to detect it is to use logic gates with the inputs coming from Q1 and Q2 of hours unit and Q1 of hours tens.The project must preset to 01:00:00 and not to 00:00:00 since the last display is 12:59:59.

By the way ,I've got something to ask about your clock using only crystal oscillator for the second's pulse.How did you do it e.g., dividing frequency or it is just that there is an available 1Hz crystal oscillator?Could you also give (e-mail is also fine for your own private property ) the equivalent circuit so that I could clearly differentiate from mine.And also which is more reliable or accurate digital clock?However,most probably could be yours I think since crystal oscillator is a stand-alone and does not depend from any external source not like mine which actually depends on power line frequency and which is also subject to vibration that causes changes on clock display.

Another quetion is that do you have also Time Setting Mode with your digital clock because the most most problem I have for now is to set the time at a correct or desired TIME.

By the way what is the format display of your digital clock is it still the same with mine 12:59:59 or 11:59:59?


Again ,THANKS a lot of your reply.

j_f_duluguin@yahoo.com

 

[renren1227]

can u send me the diagram of the digital clock?
thnx