how can i restart my circuit 74ls90 and 74ls47 and ic 555 timer

 

hi ryan,
Use the RESET pin on the 555 IC.
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Do you have a circuit to post.?

 

how can i restart on any time, ex: start from 0 to 3 or 4 and i want to repeat it from beginning (0)

 

hi ryan,
The Reset will always start the 7490 at zero count.
To start at a fixed count you need a parallel load type counter.
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Hello,

Have a look at the pocket databook to choose a suitable chip.

Bertus

 

i want to restart my counter from beginning,
i want to restart in any number, its rest only when its finish

 

hi,
Look at this IC, it has a parallel load option.

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you tell it will not restart in 74ls90,
how can i rest circuit?

 

hi ryan,
This will Reset the 555 and the 7490.
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hi, my count just stop but i want to return to zero

 

hi, my count just stop but i want to return to zero

Try this way.
As long as the button is held down, the counter will be reset.
When the button is released, the counter will begin counting.
Alternatively (not shown), if you differentiate the reset input signal (to produce a short pulse), then when the button is pressed, the counter will reset then continue counting from 0.

 

how can i restart count in middle of count
ex: start from 0 to 3 or 4 and i want to repeat it from beginning (0)

 

Hi
You cannot with a 7490 IC.
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how can i restart count in middle of count
ex: start from 0 to 3 or 4 and i want to repeat it from beginning (0)

As ericgibbs stated, you cannot. To restart in the middle of the count, you must be able to "preload" the desired value.
The 7490 doesn't have that capability.

 

thank you
what about timer 555 can you restart in the middle

 

thank you
what about timer 555 can you restart in the middle

Restart what? You can’t restart a count without counters. A 555 timer doesn’t count... it can be used as a clock signal whose pulses can be counted - by external circuitry. It doesn’t count by itself.

 

thank you
what about timer 555 can you restart in the middle

The 555 is not a counter. Its a timer. in your circuit it is configured as an astable multivibrator and used as a clock generator. To reset the counter in the middle you have to know total count. You can reset the (up) counter at any point in the count with some additional logic, but after reset, it will begin counting from zero or nine.

 

THANK YOU ALL

 

hi ryan,
You could use a 74LS192 as I shown in post #7.
It is a parallel load Up/Down counter,
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