Author Topic: OpenSource board with Cortex-M4  (Read 2642 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
Want to quickly design your own effects patches for the Spin FV-1 DSP chip?


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  :)