Searching \ for 'Siren sound -Reply' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/io/audio.htm?key=sound
Search entire site for: 'Siren sound -Reply'.

Truncated match.
PICList Thread
'Siren sound -Reply'
1996\10\09@134316 by Mark Jurras

flavicon
face
I think "Happy Birthday" at 130 dB would be about as effective as a siren.

How about the PWM on board the 'C84 otherwise a NE555 with a few RC networks
and a couple control lines from the PIC could do it. I have an old
ultrasonic pest repeller that uses the 555 that way.

- -Mark "No bugs at my birthday party!" Jurras

>>> Gregg Kricorissian <spam_OUTgrkricorTakeThisOuTspamCCS.CARLETON.CA> 9 October 1996  11:24 am
>>>
Howdy,

What I need must be such a common thing, that I thought I'd ask the PIC
list's assembled wisdom before I set out to possibly re-invent the wheel.

I'm using a 16C84 for an alarm controller, and I'd like to use the PIC to
also generate a "siren" waveform (to be externally amplifed), rather than
build that function in separate hardware.

The other approach to keep cost low would be to use a dedicated "siren
sound" IC, but I haven't found a commercial one yet.  I do know that they
exist as tiny COB (chip on board) modules in cheapo personal alarms, but
does anyone know of any sources for them... Digikey lists some COB modules
that generate melodies such as "happy birthday" etc, but can't supply one
for a siren sound.

Basically, what the siren waveform needs to be is as follows:

1. a frequency modulated square wave output, (ie: *not* being amplitude
modulated, should make it easier to do)

2. output waveform is centered on 3 kHz.

3. waveform should sweep back and forth between say 2500 and 3500 Hz, at a
rate of 15 Hz or so.


A routine with settable parameters for the frequency deviation (sweep) and
sweep rate would be ideal, to optmize the "effectiveness" of the sound
produced ... the trick is to resonate with the output transducer.  Of
course, armed with the basic routine, I could (and would) add the settable
parameters.

Many thanks in advance for any help that may come forth.
....Gregg

1996\10\09@182128 by Martin McCormick

flavicon
face
       Siren sounds are just music in which the count that determines the
timing gets changed after every so many iterations of the loop.  Each cycle
happens when a register counts down to 0 or up to some number and then
a branch on 0 occurs or some other kind of branch that tells the CPU to
toggle a bit on the port being used as the sound output.  You get a steady
tone when the cycle register is set to the same value each time.  If the
cycle register is set to a progressively larger and larger count each time,
the pitch drops because it takes a little longer for each new cycle to
occur.

       The pitch starts to rise when the timing count for the cycle register
reaches some predetermined value and the second half of the wail kicks in,
causing each new cycle to happen a little sooner each time, therefore raising
the pitch.  When the timing count reaches some preset low limit, the pitch
is highest and a branch is taken back to the first half of the routine which
lowers the pitch again.

       The speed of the wail can be varied by including yet another loop
that causes the cycle register to receive X number of timing counts before
the count is incremented or decremented.  That is pretty much what's behind
a siren sound.

       There are a few other hints.  Your loops need to be written such that
the timing is consistent as branches are taken.  If not, you will hear
tiny gaps in the tone like a ticking sound that is due to the fact that
it occasionally takes a little longer to toggle the output because the
CPU was busy doing something else.  The trick is to waste a few cycles
with NOP's such that branches take the same amount of time so that the ticks
are gone.

       Interrupts that occur while tones or sirens are being made will make
for some weird effects.  You may or may not like this, but keep it in mind.

       The code needed to do this can take lots of forms, so that part
is an exercise for the reader.  There should be several ways to make this
happen.

Martin McCormick WB5AGZ  Stillwater, OK 36.7N97.4W
OSU Center for Computing and Information Services Data Communications Group

1996\10\09@182149 by fastfwd

face
flavicon
face
Mark Jurras <.....PICLISTKILLspamspam@spam@MITVMA.MIT.EDU> wrote:

> I think "Happy Birthday" at 130 dB would be about as effective as a
> siren.

   Agreed.

> How about the PWM on board the 'C84

   How about it?  The 16C84 has no onboard PWM.

   -Andy

=== Andrew Warren - fastfwdspamKILLspamix.netcom.com                 ===
=== Fast Forward Engineering - Vista, California          ===
===                                                       ===
=== Custodian of the PICLIST Fund -- For more info, see:  ===
=== http://www.geocities.com/SiliconValley/2499/fund.html ===

1996\10\09@195302 by Gregg Kricorissian

flavicon
face
At 01:23 PM 10/9/96 -0400, Mark Jurras wrote:

>How about the PWM on board the 'C84 otherwise a NE555 with a few RC networks
>and a couple control lines from the PIC could do it.

>>>> Gregg Kricorissian <.....grkricorKILLspamspam.....CCS.CARLETON.CA> Request:

>I'm using a 16C84 for an alarm controller, and I'd like to use the PIC to
>also generate a "siren" waveform (to be externally amplifed), rather than
>build that function in separate hardware.
etc etc...


Hi Mark,

Many thanks for the quick response.  However, unless I'm mistaken, the 'C84
is not the one with the internal PWM.  Control lines from the PIC in this
design are now fully allocated, and all I have to left for the alarm
function is a simple enable.

I've thought about using a CMOS 555 to generate the waveform, but the siren
IC's do the whole banana in the same real estate as one 555 ... also, no
external components required.  Kind of hard to beat ....

Let's see what the list can turn up.

Cheers,
....Gregg

1996\10\10@083645 by Mark A. Corio

picon face
In a message dated 96-10-09 14:24:22 EDT, you write:

>How about the PWM on board the 'C84 otherwise a NE555 with a few RC networks
>and a couple control lines from the PIC could do it. I have an old
>ultrasonic pest repeller that uses the 555 that way.

Instead of a NE555, you could use PIC12C508 (8-pin PIC) and NO external RC
networks.  With 6 I/O available, you could even implement multiple timers.

Mark A. Corio
Rochester MicroSystems, Inc.
200 Buell Road, Suite 9
Rochester, NY  14624
Tel:  (716) 328-5850 --- Fax:  (716) 328-1144
http://www.frontiernet.net/~rmi/

***** Designing Electronics For Research & Industry *****

1996\10\10@200522 by Robert Lunn

flavicon
face
>Instead of a NE555, you could use PIC12C508 (8-pin PIC) and NO external RC
>networks.  With 6 I/O available, you could even implement multiple timers.

   Here we go.  Six months from now

       'Instead of <device> you could use 12C508...'

   is going to drive us all crazy!

___Bob

1996\10\10@202840 by Miller, Steve

flavicon
face
>>Instead of a NE555, you could use PIC12C508 (8-pin PIC) and NO
>>external RC
>>networks.  With 6 I/O available, you could even implement multiple
>>timers.

>   Here we go.  Six months from now

>      'Instead of <device> you could use 12C508...'

>   is going to drive us all crazy!

>___Bob

Bob,

Rather than expecting it to drive us all crazy, I hope it (the 12C508)
allows us to make some easy money.  Think of all the simple jobs that
presently require gobs of messy TTL and timers to monitor a few inputs
and produce one or more outputs.  I hope to be able to shoehorn many of
these into sub-one-dollar parts like the 12C508, because I can market
these cheap, one chip solutions that require very few external
components.  Many simple projects and/ or ideas never get implemented
because we can't hit the price point.

Sure, I like the big exotic projects too.  But I'll take easy money
whenever I can get it!  I have high hopes for the 12C508 and 12C509.

----- Steve

1996\10\10@204748 by Robert Lunn

flavicon
face
Steve Miller wrote:

>Sure, I like the big exotic projects too.  But I'll take easy money
>whenever I can get it!  I have high hopes for the 12C508 and 12C509.

       It's a joke, Joyce.

___Bob

1996\10\10@214334 by William Chops Westfield

face picon face
   I hope to be able to shoehorn many of these into sub-one-dollar parts
   like the 12C508, because I can market these cheap, one chip solutions
   that require very few external components.

That would be nice.  But isn't the "sub-dollar" price in quantities of
50,000 or so?  Anyone know what prices are likely to be in more moderate
quantities? (Say 100.  Or 1.)

Still, it'll be a while before the ecconamically replace a 555 ($0.39 in
ones) and couple passive components...

BillW

1996\10\10@233940 by Chuck McManis

flavicon
face
Perhaps on a quad 555 replacement. If one truely wanted to replace a 555 then
a couple of the input pins should have a/d's on them (to simulate
thresh/trigger)

It would interesting to see an implementation of the Dallas one-wire protocol
and
an LCD driver in an 8 pin package. This would make an interesting peripheral
would it not?

--Chuck

----------
From:   William Chops Westfield[SMTP:EraseMEbillwspam_OUTspamTakeThisOuTCISCO.COM]
Sent:   Thursday, October 10, 1996 6:43 PM
To:     Multiple recipients of list PICLIST
Subject:        Re: Siren sound -Reply

   I hope to be able to shoehorn many of these into sub-one-dollar parts
   like the 12C508, because I can market these cheap, one chip solutions
   that require very few external components.

That would be nice.  But isn't the "sub-dollar" price in quantities of
50,000 or so?  Anyone know what prices are likely to be in more moderate
quantities? (Say 100.  Or 1.)

Still, it'll be a while before the ecconamically replace a 555 ($0.39 in
ones) and couple passive components...

BillW

1996\10\11@091120 by Larry G. Nelson Sr.

flavicon
face
At 09:08 AM 10/11/96 +1000, Robert Lunn wrote:

>    Here we go.  Six months from now
>
>        'Instead of <device> you could use 12C508...'
>
>    is going to drive us all crazy!
>
>___Bob

True but it is a very viable solution. It will use less board space,
potentially less power, be more accurate, and eventially may even cost less.
I have been told many times that a 16C54 is overkill for a job but when they
are off the shelf while the "sane" solution takes more board space and has
an 8 week lead time overkill is often better.

Larry G. Nelson Sr.
L.Nelsonspamspam_OUTieee.org
http://www.ultranet.com/~nr

1996\10\11@222626 by Robert Lunn

flavicon
face
>>    Here we go.  Six months from now
>>
>>        'Instead of <device> you could use 12C508...'
>>
>>    is going to drive us all crazy!
>>
>>___Bob
>
>True but it is a very viable solution.

       I know.  That's the _point_.

       There wouldn't be a person on this list who can't think
       of <insert huge number> of uses for 8-pin PICs.

       Whenever I talk to people about them, they get a slightly
       glazed, ever-so-far-away look in the eyes.  Then they start
       to mutter quietly under their breath.  Then they excuse
       themselves, and walk away quickly looking over their
       shoulders...

___Bob

1996\10\12@152531 by William Chops Westfield

face picon face
       There wouldn't be a person on this list who can't think
       of <insert huge number> of uses for 8-pin PICs.

Of course, part of the "neatness" is in the steps taken to allow an 8pin
PIC to be useful.  Put an internal oscillator and reset circuitry in
there so all I have to add is power and software, and I'd be interested
in all sorts of different pin counts...

BillW

1996\10\12@212258 by Larry Griffin

flavicon
face
William Chops Westfield[SMTP:@spam@billwKILLspamspamCISCO.COM] wrote:
>Of course, part of the "neatness" is in the steps taken to allow an 8pin
>PIC to be useful.  Put an internal oscillator and reset circuitry in
>there so all I have to add is power and software, and I'd be interested
>in all sorts of different pin counts...

They _are_ in there, Bill!

Attachment converted: wonderlandfive:WINMAIL.DAT (????/----) (000040C5)

More... (looser matching)
- Last day of these posts
- In 1996 , 1997 only
- Today
- New search...