So I understand If Blue 1 is written high, and Black 1 low, then A turns on.
What I don't understand is what the others are supposed to be set to. Can somebody explain it to me?
But what do Blue 2, 3, 4 do then?
Ok, so LEDs have built in diodes to prevent back flow. Now I get Multiplexing, thank you.
So if I wanted to switch on some transistors instead of LEDs, things get a bit more complicated...
Well, I actually need to drive about 20ish vibration motors, not LEDs. But I think most of the concept is the same.
I would use a 5 by 5 array to get 25 outputs for the cost of 10 pins. I would need 5 NPNs and 5 PNPs to control the flow of my non-Arduino power through the matrix. I would also need 5 diodes to prevent reverse flow on the positive lines. Is this correct?