Static electricity? Fried board?

Forum 2005-2010 (read only) General Frequently-Asked Questions
#1

Dear forum

I’m experiencing strange behaviour nomatter what program I test. To keep it simple:

  1. I upload the pushbutton example without wiring any external devices
  2. I wait
  3. The control LED instantly lits up! (I swear didn’t push any buttons!)
  4. If I touch digital in 3 (set up in the example) the control LED light goes out
  5. Sometimes when I move around the table the control LED flickers.

What can be wrong? I’m really lost.
Carl Emil

#2

The digital inputs have such large resistance that if you do not tie them high or low with a resistor they will float in the middle. Their level will depend on how many electrons are trapped on them. This is easily changed by a static charged touch.

Wire up the switch and resistor and everything will be good.

#3