Understanding 555 Timer Monostable Mode

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Can anyone please tell me what does this sentence means ?


In the monostable mode, the 555 timer acts as a “one-shot” pulse generator.
 
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"Monostable" means that the device has one stable state that it can remain in indefinitely.

When set in monostable mode, a 555 timer will remain with a LOW output (the stable state) until the cows come home. When it is triggered, it is kicked into an unstable state, with a HIGH output.

After a specific amount of time, the 555 returns to the LOW, stable state.

One trigger produces one output pulse. That's why it's called "one-shot".
 
If I connect a potentiometer with the Trigger, would I be able to get HIGH & LOW immediately one after another ?
 
In astable mode, the 555 timer puts out a continuous stream of rectangular pulses having a specified frequency.


So this means that in the Astable mode, the 555 timer is having continuous pulses, which means that continuous HIGH & LOW are being generated in this mode ?


Right ? !
 
one-shot is a self resetting timer.. in ladder logic the same bit location being true is what resets the timer.. know what I mean?

And the duration of pulses produced by the timer is equal to the timer value

The one-shot only keeps the output address that starts the timer true for one PLC scan...then returns low once reset.

Hope I helped...