[sdiy] STM32 processor

[Eric Brombaugh]

I've been playing around with a low-end ARM Cortex-M3 processor for a 
few weeks that may be of interest to the digitally-minded here:

http://members.cox.net/ebrombaugh1/embedded/stm32breakout/index.html

This is a little breakout board for the smallest of the STM32 F1 family 
parts. These little devices should be particularly interesting to the 
Synth DIY community because they have dual on-chip 12-bit DACs, and the 
cost is very low (less than $3/ea in single qty).

I've gotten several simple synthesis applications running on this part - 
for example, a dual interpolated wavetable oscillator with exponential 
CV response and 250kHz output sample rate that takes up less than 2kB of 
flash code space. I can imagine that there are other potential uses such 
as sequencers, envelope generators, MIDI-CV, etc that are possible with 
these parts.

Note that ST has a demo board for this family that has a somewhat larger 
part than the one I used above and is very reasonably priced:

http://search.digikey.com/scripts/DkSearch/dksus.dll?WT.z_cid=sp_497_0928_buynow&site=us&lang=en&Enterprise=44&mpart=STM32VLDISCOVERY

Downside is that the pin spacing on their board is too wide to fit most 
solderless breadboards, but at that price it's probably worth a look anyway.

Eric