Hi Protonerd,
Thanks for creating this awesome board. I recently bought a V3 for a saber I built and it's working great. The DIYino with FX-SaberOS is a scratchbuilder's dream.
I'm starting another saber and I'd like to have more LED's. Other than D11, D12, D13 and A0(D14) are there any pins that can be used for custom I/O? It looks like D3 and D4 aren't used, but there are no breakouts for those pins.