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rookie11
- 29th February 2008, 23:43
Hi everyone,

I've been experimenting with various piezo's and buzzers from Digikey for my PIC project but could not find or generate anything that is pleasing to the ear or to my liking.

What I want to emit is a sound similar to what comes out of a cordless phone, or a mobile phone. I don't want it to be a song, or anything annoying like an alarm beep so I don't need a voice chip or anything like that. I want the component count, size and price to be as small as possible as well.

Does anybody have any suggestions or have done this in the past? The sound I need to create should be as loud as a cordless phone's medium/high setting. I've been googling and came up with small 8 ohm speakers but not sure if a) these would be loud enough, b) I can get it to sound like a cordless phone warble type, and c) if PICBasic is able to generate the tone for me.

Thanks for any help and suggestions.

rookie11
- 7th March 2008, 02:40
What I learned is that I need to generate, say, 2 or 3 tones on different pins, and tie them together.

I found an interesting example done using another compiler (http://users.picbasic.org/projects/making_music/) and interrupts. In my application, I don't really see the need of using interrupts since gerating this chime will be the only thing that my PIC will be doing.

What I don't understand is how to do is generate 3 frequencies at the same time on 3 different pins. Any tips on this?

skimask
- 7th March 2008, 14:17
What I learned is that I need to generate, say, 2 or 3 tones on different pins, and tie them together.
I found an interesting example done using another compiler (http://users.picbasic.org/projects/making_music/) and interrupts. In my application, I don't really see the need of using interrupts since gerating this chime will be the only thing that my PIC will be doing.
What I don't understand is how to do is generate 3 frequencies at the same time on 3 different pins. Any tips on this?
Well, if you check that code, and take a look at the PBP manual, you'll find they are very similar. Most likely the other code will probably port right over to PBP format with very few changes.

Archangel
- 7th March 2008, 17:12
Hi Rookie11,
word on the street is square wave output from a PIC is rather harsh, and to put an inductor (choke) in series with the output to soften up the pulse train into something more like a sine wave.