Author Topic: OpenSource board with Cortex-M4  (Read 1976 times)


OpenSource board with Cortex-M4
« on: April 17, 2016, 11:09:45 AM »
Hey guys,
mu first post here.

I want to share with you a design I'm working on for the past month.

It's an opensource board based on STM32l476 with a PCM3070i.

This provide a 80MHz Cortex-M4 processor and a 192ksps codec with integrated DSPs. For now the schematics are done(the first review) and I'll start the layout.

Any toughts, sugestions and criticism are welcome.

The repository:

The WIP is in rev0 branch.

Digital Larry

Re: OpenSource board with Cortex-M4
« Reply #1 on: April 20, 2016, 10:52:12 AM »
Well I generally like to be encouraging.  How is this different than the Hoxton Owl board?

Also, I saw a program "Audio Weaver" that claims to be compatible with some ST-Micro dev boards.  Would be great if that could be made to work on your board.  I think writing code for effects (at least, doing it more than once) is almost as painful as soldering!
Digital Larry
DSP tinkerer and former transistor twister


Re: OpenSource board with Cortex-M4
« Reply #2 on: April 20, 2016, 12:35:30 PM »
Hi Larry,

Thinking about hardware Hoxton Owl have a little more powerful microcontroller specification and little less power processing in the codec.

In concept the boards have some difference. I plan to focus in the moments when you're playing at home and studying. To me this is a problem since I'm a father of 2 and the time that I can play is when my kids are probably sleeping. So in the future versions of this board it will be more like Vox Amplug series and less like a "traditional stmop box.

I'm also targeting that this board will cost less ( US$ 49)  but I can't promise even that I'll be able to produce it to sell. My first idea was to have an FPGA on this board ( I'm a professional HDL designer for the last 7 years) but avoid it for now to meet the target price. Given that I live in Brazil and even this cost is prohibitive here(10x to convert from US$ to R$ and US$ 49 is half of our minimum wage).

Also my design approach is friendly for modifications :) The whole achematics are provided in a modular approach to maek easy to reuse trough the libraries plugmodules/pluglib.

From software perspective I was not aware of Audio Weaver, nice software. I'll take a look when the time comes.
I'm planning to have something similar to gnuradio gru interface, and also a similar processing module scheme, but this is something for the future  :)