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Different wait times in IC output.? Answered

Hi, is it possible to make an output with different Wait Times? The numbers are the time in seconds. The HI would be the enough to make a buzzer beep, like half a second... I was thinking of 555 ICs, but I don't think it's even possible to do this with them. Do you suggest any IC that can do this? I just want a buzzer (or whatever) to beep like: Power On - 30sec - BEEP - 180sec - BEEP - 30sec - BEEP - 180sec - BEEP, etc Thanks.


This could be done with a flipflop set to change the interval on a timer. Especially since you want two time intervals. I'd have to think about the circuit some and maybe do some searching. Could you use a random time? It looks like you are trying to build an irritator. Am I right?

Nope, you are not. :)
I'm just trying to make a beeper to aid me in making exercise (gotta keep fit, 'mirite? ). Like this:
For 30 seconds, you run like mad; for 3 minutes, you jog. Repeat.
It's hard to do this while looking at your watch, so I thought on making a simple circuit and maybe even an instructable, because there's none about this kind of timers (that I know of).

Could you please show me the output of the Flip Flop mode? I can't find it anywhere..

You're in prime "Arduino" territory really. This is dead easy with something like a Lilypad arduino. Steve

Do you have a DOHC 4-cylinder engine in your lawnmower? Do you use a satellite uplink to open your garage door? Using a microcontroller to produce a single pulsed output is overkill! seandogue's suggestion to use 555 ICs (one as a one-shot, and one as a multivibrator) is the most sensible option here. After all, the 555 was designed just for such an application!

Do you have a clue ? The 555 was certainly not used for long times, if you wanted any kind of reliability. Running a 555 for 180 second time outs ? No, you run it at say 0.18 seconds, and you run the OP into a Divide by 1000 stage, and then you have another 555 running at .03 secs and another divide by 1000 stage. You do that, not least because the timing capacitors will leak too much to give anything like repeatable time. Using a single chip micro, (<5 USD) as a single logic function like this is actually CHEAPER and easier than using a 555. The code takes 30 seconds to write, if you know the CPU, and all you need is a single crystal and two caps to get going.

So you want me to use relays? (race ~= species <=> type of object) Aren't they just.. switches? I never really used relays before.. (Yeah, I shall die one day.)

You could make an audio track and just play it? L

Well, that sounds lame/overly obvious.I like some challenge when making stuff. :) Thanks anyway. :D

Well, do it with clockwork then? (challenging)


My personal best answer. A nicely lateral solution.