Midi not working after build

So after a pretty non eventful build, I had fooled myself into thinking I was only moments away from calibrating and hooking this up to my sequencer and do some work with the Shruthi and my SammichSID, when much to my chagrin I’m not getting any midi data. Checked the filter board for sound by holding button 1 down and getting sound, and all the pots and switches are active and I’m seeing their data on the LCD so what now? Thanks Barry

hi Barry,
first thing to check (if you haven’t done already) would be if the opto is put in the right way (and no pin bent under the ic).
diode polarity, right resistors?
or maybe a bad solder joint…

Diode. I had misread the directions, and thought that when it said the stripe goes in the opposite direction of D1 I though it said opposite direction on D1, thinking that there must have been an error on the solder mask when it was printed. Now I’m midiing away! Thanks Barry