The livingroom coffee table has long been a favorite realm of the model railroad. But what to do when you actually want to have coffee? [Peter Waldraff] has come up with a most eloquent answer to the ...

OK. A bit more reading and head scratching.... let's see if I have this right. Resistor values chosen for 0.5mA current flow. DCCOD > Arduino one. Tie the 12VDC and 5VDC power supply grounds together, ...