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Where have you actually come across a 555 timer in the wild?
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Neilm:
I had to make a small plug in device to allow the product I had designed to be run under computer control. I put a 555 in it to generate a square wave - see pin toggle real device present.
david77:
In my 20 EUR cheapie toaster, used as timer for the bread ejector thingie. With the obligatory knob on the side to choose how burnt you'd like your bread.

I've used it and will continue using it myself for all kinds of things, but you can hardly call what I do "production".
steve30:
They are used in some 68000 based computers in the reset circuit (including the Amiga 500+). Can't remember exactly what it does though. We had an educational 68k board at college, and the documentation explained its purpose, but I forget.

They are quite old designs though. I very rarely see 555 chips in use in products. Or at least not ones that are marked with '555'.
lapm:
Last time i run into one on wild was one of those orange road flashes. The 555 was running flashlight bulb throw transistor.. Transistor had died, so needed replacement.. Was beyond me why friend of mine wanted it fixed instead of buying new one...

Something like this one: http://thumbs3.ebaystatic.com/d/l225/m/mM8ExgkRmnUqsEXf0TITuUg.jpg
magetoo:

--- Quote from: Phaedrus on April 01, 2014, 04:01:38 pm ---
--- Quote from: magetoo on April 01, 2014, 12:44:30 pm ---Are you sure?  I thought this function was integrated in the chipsets everyone use.  (Or is it considered "legacy hardware" nowadays and has been dropped?)

--- End quote ---

I haven't seen it in a while, so I guess it's deprecated. But I remember seeing it on an old Asus AMD board, socket 939. And I thought I've seen them on a few other motherboards as well.

--- End quote ---

I meant the other way around, older machines will have something that is compatible to an actual 82xx (or whatever the number was) timer chip, not a 555, and probably needs that compatibility to be able to run DOS or something.

So I imagine slightly newer systems that don't need the compatibility could have dropped it and used something else for a beeper instead, like the 555 triggered by a GPIO.  (And anything recent would get rid of the internal speaker altogether.  Or use a "real" audio chip?)

Historic note: In the original PC, the timer chip had three separate timers - it generated a periodic interrupt at 18.2 Hz for DOS, drove the speaker with another timer, and also did a third thing I can't remember.
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