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Pre-Recored Voice on Chip

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Hello All,

I am a novice to most of this, still a student at a community college...
I am trying to build a talking GPS unit...
I can't seem to find the right chip to use to store and play back the audio.
I found a few "Text to Speech" chips, but the sample audio on line was not good...
So my next idea was to pre-record the audio elements needed,
then load them on a chip of some sort.
I have a list of about seventyfive words in all.
Like ONE. TWO, Twenty, Fifty, North and so on..
Place the elements on some kind of chip, each speech
element with its own addressable location and the
Pic 18F will parse out the incoming serial string,
pick the voice elements in the order needed and
send the audio on its way....
I have not rcorded the voice yet, I am not locked
into a file type, .WAV or other format is fine.
I would like solid telephone quality audio playback.
Say a sample rate of 8kHz, 80Hz to 3kHz, max storage
time is 120 seconds should work ???
Thanks in Advance,

Tempe Arizona
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You might consider the voice record play back IC's by Winbond,
such as the ISD4002-120PY.
Hi ajsklar, the TalkBotBrain (thanks for the mention Mike) would probably do it although it is pushing your requirements a little as it is just below "telephone quality sound" although it does have built in tiny amp and will make understandable speech.

The TalkBot will hold up to 250 separate sounds (like words or partial words) with the limitation of total combined 24 seconds of playback. I made a talking thermometer using just the TalkBot and 31 stored spoken words which you can see here; Source Files

And one of the projects I was planning for Christmas break when I get some time was a talking GPS unit.

The Talkbot would limit you to about 50 words (that's about all you get in 24 seconds), but is very easy to play each word with just a 2byte serial command.

Also it's big benefit (since you are a PIC user) is that it comes complete with a PIC 16F628 on board that you can program (with USART) so it has everything you need to receive the GPS serial output and just speak it out. So you don't need any other PIC or any other hardware it IS the entire talking application.

That type of application is what it was designed for. It also has a few other benefits of very low power consumption when not talking and compact size, fully pre assembled etc.
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Hello All

Thanks for your answers so far...
It looks like the "Talk Bot" is somewhat close to what I am looking for...
But its not there....
I have had a few helpful emails with its developer...
I may end up trying this just to see what happens...
If you have any ideas, please feel free to post....
Tempe AZ
The ISD chips are 256 level per cell eeprom with associated analog input and output circuits. You can buy them from 10 secs to 4 minute storage lengths.

Because it is audio it is not as strick on errors in the 256 level playback as if it was trying to do actual data byte storage.

NAND flash like used on thumb drives and SD Cards are prone to errors and have error correction algorythms in the read function. There are some two level flash cells on the market.

The cost of NAND flash is getting so low it is being used instead of the ISD chips. You have to do more work on hardware and software to use an SD card for storage. Compared to the map data though it is a small adder.

You can record segments and recall them by addressing and chain the various segments together.
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Hello All
It seems that I may have found what I am looking for.....
**broken link removed**

It looks like the 51XX or the 40xx chip will work...
So now I have a project to do over the winter break...
I am still not clear on the "I2C" connection....
I wonder if this can be run in conjunction with
a PIC18F chip, we use the 4550 in class, thats
one reason why I picked that chip...

Tempe Arizona
Hello All

Well I had to go to plan "B" on this...
Good news, I found a programming board for the ISD 4002...
Bad News, Its in Poland....
More bad news, They want $500.00 USD for the board...
Real bad news, I'm a college student, I cant afford that !!!!
I found something else that might work....
SparkFun Electronics - SOMO-14D Audio-Sound Module
I have one on order, should have it next week...
I will keep you posted...
Another alternative might be using a demo board available from Digikey. It has a 240 second Win Bond chip under a blob of epoxy, 5 pushbuttons for play, record, fwd, erase, reset, and volume. It also has an SPI interface available. All that on a board aprox 1 3/4 by 2 inches - for $13.30.
There are a few software examples for using the SPI interface around the net -

You can record lots of words in 240 seconds.

A stand-alone 28 pin chip available for $12.00

I am using a stand -alone chip, interfaced to a PIC, to replace the pushbuttons, however it would be possible to "tack-solder" wires to the pushbuttons and let the PIC replace them.

DigiKey part number



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