A situation in place was the next – my half done amplifier was working already 3 years just proving the statement “there last longing device is a temporary one”. It was kind of fine – but it consumes an energy. In a fact a solid chunk of the energy – it is class A amplifier. At some point in time I started to think – why to not switch on/off the amplifier in dependence on the signal presence.
I have added a small additional pcb for my diy amp project, which is dedicated to detect the drop of VDD voltage level and saving the data to EEPROM at reaching of the certain threshold. All how I described here, I used the built-in comparator from PIC168f877a.
It is a pity that I have not added this feature to the main pcb, so now all solutions looks unaesthetic.
The code of the DIY amplifier has grown much, it is harder and harder to debug it and keep in the order. So first of all I have added the audioprocessor part to the existing code, not much to discuss it is already been considered. Only one thing – I added the display LCD functions instead of the uart menu. I still want to have the USB connectivity so I can take control over amp from the PC. The plan is to use the FT232 with the virtual com port. Of coarse, it would be a nicer way to use PIC18 with USB on-board, but at the moment of time I did not have the experience with it, and now, when I actually have it – I would still go the virtual com path, usb has too much of the hustle to implement and handle nicely, besides it is not free for use as usual usb.