Grumpy_Mike:
red913:
. But what I did understand was the current on my pins should be fine.A pity because that is not what he said.
A current of 20mA is fine but the sum total of all currents is a bit more complex. So while each pin can supply 20mA you can not get 20mA out of all the pins at once.
Look at the port mapping pages on this site to see what pin numbers correspond to what port numbers.
Ok, thanks. I took a look at the pin mappings. I got that figured out. So if I do 4 pins on 4-7 and the last 4 on 8-11 that will evenly distribute the pins, and theoretically the load, among ports B and C.
But let's say all 8 pins are off(power from segment pins grounded through Arduino pins set low)and I'm sinking that full 20mA from each pin. It says the sum of those ports can't break 100mA. So I don't see how that would happen. Would you be able to elaborate for me please? I know you said the sum total is more complex. So I'm assuming it's more than 20+20+20+20=80.