hamster

Playing back audio from SDRAM.

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I've been inspired to play around with audio streams, and here is my first project:

 

http://hamsterworks.co.nz/mediawiki/index.php/SDRAM_Audio_playback

 

You can send 16-bit stereo data down the serial port, and it writes it to RAM and plays it back. Quick enhancements would be for it to only play back what was written or for it to clear the SDRAM before anything happens.  At the moment it doesn't do either of these because I wanted to see how long the data would last in SDRAM when I removed and reapplied power.

 

It could also be used as the basis of a wave-table synth, however 8MB of samples does take a long time to download through the serail port at 115200!

 

Cheers

 

Mike.

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Mike: I have a 3-mbit serial player with ZPUino, in case you're interested. Plays stereo 44100Hz/16bit with not many drops. :)

 

It's mostly done by software.

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I've managed to connect the whole thing to my FM transmitter project, so it can now download and transmit samples.

 

So if you want to give it a try.

 

a. Download the zip file

b. Send the bit file to the papilio pro

c. Put any old jumper wire into A0.

c. Tune an FM radio to 91.0 - you should hear nothing

d. Write the file named 'data' to the serial port with "stty 115200 < /dev/ttyUSB1; dd if=data of=/dev/ttyUSB1"

e. Enjoy!   

 

I'll upload the source for the design later.

upsample demo.zip

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I've managed to connect the whole thing to my FM transmitter project, so it can now download and transmit samples.

 

So if you want to give it a try.

 

a. Download the zip file

b. Send the bit file to the papilio pro

c. Put any old jumper wire into A0.

c. Tune an FM radio to 91.0 - you should hear nothing

d. Write the file named 'data' to the serial port with "stty 115200 < /dev/ttyUSB1; dd if=data of=/dev/ttyUSB1"

e. Enjoy!   

 

I'll upload the source for the design later.

Nice! I think I will give this a try.

Edit: Lol! Works like a charm!

rick-roll-o.gif

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