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Simple Electronics For Software People

One thing I have gotten good at in the last year or so is doing minor repairs on my kids toys.  The latest problem has me stumped.  We have a small plastic dog with a 'leash' string emerging from it's back.  When you pull the string, the dog barks and snuffles.  This has recently stopped working. 

I opened the dog up and I cannot see any obvious problems like loose wiring.  There are a few wires, a speaker, and a chip.

This got me thinking that it would be fun to put my own sounds on the chip.  I'm a software guy and I am not sure how to start.

Can I buy a chip/small board that will have enough memory to hold and play a .wav file?  Could I get a USB device attached to a PC for use in downloading the sounds onto the chip?

Can you help this aspiring toy master?

Emmet Jackson
Tuesday, May 6, 2003

Surely you should get the barking and snuffling back first before you get the dog quoting The Simpsons?!

John Topley
Tuesday, May 6, 2003

That's the problem with software people - we think of all these cool features we want and forget the most basic things. I mean, I bet it can't lick its own bits can it?

Tuesday, May 6, 2003

I wouldn't count on the sounds to be in something like a .wav file... something that simple probably doesn't even have a file system. If I had to guess, it's some raw binary stream burned on an EEPROM that gets fed to a synthesizer, the data bits may even be intermixed with the synthesizer control bits.

You could at least look up the specs for the chip in the toy.

Tuesday, May 6, 2003

On second thought, something that simple might even just be a CPLD instead of a full blown processor. Who makes the chip, and what part number is it?

Tuesday, May 6, 2003

If you're going to wire your own, be sure to check out

Tuesday, May 6, 2003

this is for Big Mouth Billy Bass, but would probably be helpful for you

Tuesday, May 6, 2003

There are chips out there that directly record and playback audio. All you need to add is a microphone and a speaker, and a little address logic, and you've got a player. No wav files or CPU required.

Chris Tavares
Tuesday, May 6, 2003

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