This discussion was created from comments split from: Problems getting Braids to update firmware.

Hello guys, where can I find circuit diagram for shruthi synth?


Control board

SMR4 mkII Filter board

Hey pichenetts, Thank you so much. I am working with STM32F4 these days. Is it possible to integrate stm instead of atmega chip in this schematic and what variations can it be with the programming?

> Is it possible to integrate stm

You’ll have to rework the power supply for 3.3V, redo the pin assignment, add pins for the JTAG or SWDIO programmer, and rework the firmware from scratch.

Good luck :slight_smile:

Hmm, it’d be a lot of work but wow. If you considered the connection between the Shruthi digital board and the filters as a standard protocol then you could potentially design a new digital board that could do all kinds of clever shenanigans. It would be amazing if someone took it upon themselves to design a new digital board instead of just new filter, even if the new board required SMT parts and therefore wasn’t fully in keeping with the original fully DIYable approach.
Hopefully you’d be ok with that Olivier? Naturally it wouldn’t be called Shruthi or make any connection to MI other than to give credit.

Look at how the LXR does it. A DIYable main and control board, then a SMT board for the ARM CPU and ports.

> Hopefully you’d be ok with that Olivier?

Sure! I don’t have any specific attachment to the Shruthi and the DIY/non-DIY battle. Just make it clear it’s not a Mutable Instruments product…

Not that I’m in any way capable if either the electrical engineering side or the programming side. I just think it would be amazing if the Shruthi formed the basis for a general protocol for connecting digital oscillator/control boards to filter/amp boards. I’m just a dreamer though.

You could call it DCV, digital CV :slight_smile:

Is there really a need for a generic protocol for connecting digital oscillators into a VCF+VCA combo?

There’s a good infrastructure for mixing and matching various flavours of digital oscillators and various flavours of VCFs and VCAs - with plenty of models to pick from dozens of brands. It’s called Eurorack :slight_smile:

Ironically enough, one of the things users of other modular systems complain about about Eurorack is the lack of rigorous standards for interfacing different modules. Even Doepfer, who invented the format, don’t seem to stick to their own standards…