I sat down for an afternoon and finished this project. (One way I deal with dreadful grinding depression is with builds, it seems to put my mind at rest — at least when the medications don’t work). Now probably out of date I still had the parts and a set of 5 PCBs, it it was a nice, simple and easy build. Nothing really to go wrong. I see it’s already deprecated and replaced with a more up to date model but wondering if it still has any utility?
Someone’s written a USB implementation using PIO and it has Host support. Utilises 2 PIO per USB port so potentially could have 5 usb (1native + 4PIO) ports on a single device? Could be a potential start for a usb midi host multiplexer?