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rfenergy
08-24-2005, 03:39 AM
Has anyone tried to use the freqout command to cause a BS2e to emulate the sound of a siren? I don't know enough about the command and its advanced parameters to get it to mnake a smooth transition between the frequencies. If anyone has any sample code os BS2e sirens or sound effects PLEASE post them so I can stop pulling my hair out!!

Mike.

Jon Williams
08-24-2005, 06:50 AM
It's very difficult to make a smooth transition because each new FREQOUT takes a bit of time to load an this lets the output relax. What this means is there will always be a clicking sound unless you synthesize the sound via some other method.

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Jon Williams
Applications Engineer, Parallax

doggiedoc
08-24-2005, 07:22 PM
Would it be possible to generate the siren sound with discrete components and control that start/stop with the stamp?

I seem to remember a schematic in one of my basic electronics texts somewhere. I'll have to look that up.

Jon Williams
08-24-2005, 08:11 PM
Sure, you could do that -- use a 555 (or 556) and let the BASIC Stamp control the reset pin.

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Jon Williams
Applications Engineer, Parallax

rfenergy
08-24-2005, 10:31 PM
Thanks for the information guys. That makes sense about the lag in the transition time. I'll explore the alternative of using some ancillary circuitry. Thanks again for responding.

doggiedoc
08-25-2005, 04:12 AM
I found that schematic. Credit goes to Forrest M. Mims III, from the Basic Electronics Workbook.

Hope this helps.





http://www.tcah.com/images/postings/sirenschematic.jpg


I don't know what application you have in mind, but if you were to use the stamp to monitor whatever, say a perimeter trip-wire or tank fluid level. You probable could have it sound the "alarm" in the above circuit.

Post Edited (doggiedoc) : 8/24/2005 8:19:54 PM GMT