ropg@ooc.uva.nl (Rop Gonggrijp) (11/12/90)
For a phone switch I am currently developing I am looking for a chip that:
Will generate two sine-wave tones simultaneously
Is computer programmable (height of tones, and preferebly amplitude)
Works from 100 to 3000 Hz
More of these things in one package would NOT hurt....
--
Rop Gonggrijp (ropg@ooc.uva.nl) is also editor of Hack-Tic (hack/phreak mag.)
quote: "We don't care about freedom of the mind, | Postbus 22953 (in DUTCH)
freedom of signature will do just fine" | 1100 DL AMSTERDAM
Any opinions in this posting are wasted on you | tel: +31 20 6001480fmgst@unix.cis.pitt.edu (Filip Gieszczykiewicz) (11/13/90)
In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes:
For a phone switch I am currently developing I am looking for a chip that:
Will generate two sine-wave tones simultaneously
Is computer programmable (height of tones, and preferebly amplitude)
Works from 100 to 3000 Hz
Greetings. Have you considered the AY-3-9128 (I believe).
It's a PSG (programable sound generator) with 3 seperate
channels. I found it simple to program and the output
were well within 100-3000 Hz I think you can get it at
Radio Shack (expen$ive) or Jameco or DigiKey...
You can find specs in any Radio Shack cross reference
paper back.
Take care.
--
_______________________________________________________________________________
"The Force will be with you, always." It _is_ with me and has been for 10 years
Filip Gieszczykiewicz "... a Jedi does it with a mind trick... " ;-)
FMGST@PITTVMS or fmgst@unix.cis.pitt.edu "My ideas. ALL MINE!!"jon_sree@world.std.com (Jon Sreekanth) (11/13/90)
In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes:
For a phone switch I am currently developing I am looking for a chip that:
Will generate two sine-wave tones simultaneously
Is computer programmable (height of tones, and preferebly amplitude)
Works from 100 to 3000 Hz
If you're trying to generate DTMF ("touch tone"), it may be better to buy
a DTMF chip. Anywhere from $1 to $3, because they're made in large quantities,
(nearly) every telephone has one.
For other sine waves, I don't know of any good simple analog methods.
(In fact, I'd like to know some ...) It might sound like overkill, but it's
not particularly difficult these days to put a small eprom with an 8 bit
dac. Especially if you have a ucontroller on your board anyway, with an
eprom and everything.
If the two frequencies are oddball numbers, you may be stuck with needing 2
dac's. If not, you could store the waveform of the composite (combined)
signal, and re-create it. Of course, if you need independent control of
amplitudes of each component, it'll have to be 2 dacs, with some way of
scaling (either the reference, or by digital arithmetic multiplication)
For one frequency, or a composite of frequencies that have common factors,
it works out pretty reasonable. For a 50mS DTMF burst, at 8K sampling
rate, 8 bit per sample, that's less than 512 bytes of eprom per digit,
and about 4K bytes for all 10. An eprom that size, and an 8 bit dac,
are quite affordable. You'll have ultra stable frequency, known low
distortion, stable amplitude, etc.
Regards,
--
/ Jon Sreekanth
Assabet Valley Microsystems Fax and PC productsgrayt@spock (Tom Gray) (11/13/90)
In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes:
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<Will generate two sine-wave tones simultaneously
<
<Is computer programmable (height of tones, and preferebly amplitude)
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<Works from 100 to 3000 Hz
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<
<More of these things in one package would NOT hurt....
<
<
<--
Simplest way to do this (and probably cheapest) is to use a PROM.
If you want programmable - a $5 DSP will do it easily. scotto@ipars.UUCP (Scott O'Connell) (11/14/90)
In article <JON_SREE.90Nov13012237@world.std.com> jon_sree@world.std.com (Jon Sreekanth) writes: >In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes: > > > For a phone switch I am currently developing I am looking for a chip that: > > Will generate two sine-wave tones simultaneously > > Is computer programmable (height of tones, and preferebly amplitude) > > Works from 100 to 3000 Hz There is a company called Communications Specialists, Inc. who make a custom chip called the IC110. It's sole purpose in life is encoding and decoding tones. I've seen the same chip used from 67Hz to 3000Hz. They specialize in the Land Mobile Radio industry providing tone signalling solutions. Communications Specialists, Inc. 426 West Taft Avenue Orange, CA 92665-4296 714/998-3021 (Local) 714/974-3420 (Fax) 800/854-0547 (Entire USA)
whit@milton.u.washington.edu (John Whitmore) (11/14/90)
In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes: > > > For a phone switch I am currently developing I am looking for a chip that: > > Will generate two sine-wave tones simultaneously > > Is computer programmable (height of tones, and preferebly amplitude) > > Works from 100 to 3000 Hz > A switched capacitor filter (the National Semiconductor MF10 for instance) can generate sines from a digital programming frequency. So, if you can generate programmed-frequency square waves, clock one half of an MF-10 and you'll generate your sine waves. See AN-307 (National Semiconductor Linear Applications Databook) for an example circuit. To control the amplitude, note that at one point in the feedback loop (circuit of Fig. 7, op cit) the signal is a square wave; feed this square wave into the Vref port of a four-quadrant DAC, and take the DAC output to drive the filter, and you have both programmable amplitude and frequency. Or, just run a few bits worth of R/2, R/4, R/8 etc. resistors to switches to ground, and when you ground them, instant programmable attenuation. Takes two DACs for the two amplitudes, a programmable counter/ timer for the clocks that determine the output frequencies, and an MF10 dual filter chip. Total parts cost circa $12. John Whitmore
markz@ssc.UUCP (Mark Zenier) (11/15/90)
> In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes: > For a phone switch I am currently developing I am looking for a chip that: > Will generate two sine-wave tones simultaneously > Is computer programmable (height of tones, and preferebly amplitude) > Works from 100 to 3000 Hz Out of Don Lancasters "hardware Hacker" column, Radio Electronics, December 1990. Micro Linear ML2035 Programmable Sine-wave Generator. 1 Hz to 25 kHz. 1 Hz resolution with at 8.388608 MHz clock. 8 bit dip, serial input. requires plus and minus 5 V. $8 markz@ssc.uucp
gene@cooper.cooper.EDU (Gene (the Spook) ) (11/15/90)
in article <JON_SREE.90Nov13012237@world.std.com>, jon_sree@world.std.com (Jon Sreekanth) says: > In article <15621@slice.ooc.uva.nl> ropg@ooc.uva.nl (Rop Gonggrijp) writes: > > > For a phone switch I am currently developing I am looking for a chip that: > > Will generate two sine-wave tones simultaneously > > Is computer programmable (height of tones, and preferebly amplitude) > > Works from 100 to 3000 Hz The best I've seen for what you describe is the AY-3-8910 from General Instruments. This little bugger will generate up to three independent outputs whose volumes are adjustable on a log scale, variable frequency (just specify the divider of the clock reference), and can have added effects such as white noise, etc. Radio Shack used to sell it, but I'm pretty sure that a GI representative will be able to get you one, as well as literature and/or a whole databook. From what I remember, it was pretty cheap (<10bux). All CMOS, functions from hell, cheap... you can't go wrong. BTW, there were other numbers which were just as functional, such as the -8911, -912, and -8914. The -8910 has two 8-bit I/O ports which are very handy if you don't want to throw on a PIO device, but the other chips I mentioned have variations on the ports. (1 or none, for example) Here's the hitch, you pretty much need a microprocessor to program the bugger, unless you want to use any parallel port to read/write from the chip. Again, call GI and get the info. Find out if it's what you can use. Spookfully yours, Gene
robf@mcs213j.cs.umr.edu (Rob Fugina) (11/20/90)
I just saw a number I recognized...or at least it looked very similar to a chip I'm using for a doorbell...I'm using an AY-3-1350. I bought it from Radio Shack a number of years ago and never used it for anything. It's a melody synthesizer. It has 25 preprogrammed tunes and 3 chimes. The spec sheet that came with it is now well worn, and I can't read all of the values on the sample circuit schematic on it. Can anybody tell me where I could get similar specs on this chip, and possibly even a copy of the sheet that came with it from Radio Shack? They don't carry the chip any more, by the way... If anybody's interested, the circuit amounts to a power supply that switches on automatically when a doorbell button is pressed, and powers down when the chip is done playing a tune. Also 3 small circuits that set pitch and speed, a small amplifier circuit for the audio output, and last but not least, a set of swiches that choose which tune is to be played. If you can tell me where to get specs, please mail me directly... s096128@umrvma.umr.edu OR robf@cs.umr.edu THANX!