I am controlling a simple set up, 9 leds, 3.3v and 20mA each, each connected to a 100ohm resistor and plugged into pins 3-13 (skipping a couple) and they are turning on but they are very dim. Is it because they are not receiving enough voltage?

powering multiple leds

system September 27, 2012, 3:18am 4

They are set to output so I'm not sure what's going on.

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