PI never gets old - constant power drive with added bonuses.

[Teleno]

I hope yes, Teleno!
I want encurage you for what is one of the best project I have seen this year on the forum!

I appreciate your encouragement. I've modified the original circuit to the extent that a new PCB needs to be designed. The software is a bit messy and needs structuring.

If anyone with PCB skills wants to help then problems with layout, coupling, ground loops and such can be avoided. I can provide a Diptrace schematic.

The software is written in C but a C++ version would be more maintainable. I'm using stripped down versions of LCD and I2C C++ libraries converted into C code. If any C++ guru wants to help then I'll post the rather messy C code.

The PI is meant to use a 1ms period and the Atmega328P with this code can do interrupts, signal procesding, sound processing, user input capture and I2C LCD driving and still have abut 400us left over.