Can someone explain this circuit

[Amy13]

Hi I have been given this circuit but I don't quite understand how it works.

Any help is much appreciated!

Thank you

 

[Minder]

It appears to be a LED flash unit, but why do they use a 555 would be my question?
There is already a micro used, I do not use R.Pi. but do use picmicro's and do not see the reason for the 555 when the micro should perform a similar function.
M.

 

[garublador]

It looks like S1 will turn on and off the 555. Perhaps the intent is that you can turn on the 555 and let it flash the LED or allow the R.Pi to control the LED. Some context might help but it could be a circuit designed for a demonstration or learning rather that for function.

Another option would be that the R.Pi has that GPIO set as an input and it's doing something with the information about whether the LED is on or off (e.g. counting, signaling a user by some other means, ect.). Again, without context it's difficult to tell.

 

[Amy13]

I was informed that the circuit and the 555 is to simulate a winding machine because if the output the 555 produces and that the RP is in some what counting. But my mentor is wanting more information

 

[garublador]

When S1 is in one position it allows power to get to the 555. In the other position the 555 is unpowered and the LED will be off.

If the 555 is powered and S2 is open the LED will blink. When S2 is closed the LED will be off.

The R.Pi can detect if the LED is on or off.

 

[Minder]

So I assume the 555 is intended to mimic an external winding counter device, is he/she looking for more of an explanation from you?
Look up an explanation or examples of 555 circuits, there are literally 100's out there as it is one of the most popular general purpose IC's in use.
You will be able to see the way the 555 pins are connected as to what function it is performing as a counter!
M.

 

[Amy13]

Thanks so much guys been a lot of help