Count down

564

06:47:43

this circuit made from 3x7 seg displays that discount a desired time from 1 to 3 min . 
a button in the left select the time ... also under the button there is a switch PLAY/STOP discounting . 
The knob besides the 555 timer is to set a value of resistance to get a nearly discounting time depending on your smartphone CPU speed.

the circuit too complicated and not easy to make for the learners (2 hours of work ) ... so if you have a question , you are welcome :) 

Components :
one timer 
3 displays 
3 converters 
3 controlers 
18 AND function (they was 26) 

published 11 years ago

jackblack

11 years ago

it needs a too fast CPU :o

houssem199

11 years ago

absolutly yes .. you can chage the resistor value .. in the left corner you wil find it , just décrease it and it will be more faster ...

jackblack

11 years ago

okay. it's working now . thank you

northernpeso

11 years ago

Uhh counts down to 10 then jumps to 59??

houssem199

11 years ago

yeh i seen it .. i will fix it tmrw coz i'm too tired. but if you have a suggestions for help s-ow me ;)

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