[GreenKeys] Feeding ITTY to the teletype; simulating M33/35 teletypes hooked to computers like in the 70s

[epvgk at limpoc.com]

On Wed, Aug 29, 2012 at 06:31:00AM -0600, Paul Heller wrote:
> 
> On Aug 28, 2012, at 9:35 PM, epvgk at limpoc.com wrote:
> 
> > Not sure how much help I can be, but a friend and I wrote some C code that 
> > can successfully decode ITTY audio into binary data using the fast fourier
> > transform, and also code to decode the binary data into a baudot stream
> > and/or convert it to ascii. You're welcome to that if it will help. 
> 
> Please send it along, Eric.
> 

Ok, i cleaned it up a bit and made sure it still works. There's a version
that builds and runs under linux and a version that's been sanitized to run
on an 8 bit CPU (AVR atmega328p in this case) 

Linux being what it is, it may or may not be hard to capture audio from ITTY
and turn it into the correct sample format for this code. I use "mplayer"
which is available on most distributions, but I'm sure there are other ways.
For sampling actual audio from the sound card, I've used "parec" but again,
there are a million other ways to do it in linux, like "arec" or "record."

There are a couple of sample audio files in there to try it with, too.

details are in the NOTES files but feel free to ask me about it. 

you can get it in Zip or tar format from

http://wtrc.net/~eric/fftdemod

eric