Go Down

Topic: Now I really need help. (Read 717 times) previous topic - next topic

baum

None of my digital pins, except for pin 13, work. They all ouput ~4VDC and almost no current-- a 3mm green led plugged in to any of them stays off. (I wrote some simple code which pulls pins 2-13 high.)

westfw

did you remember the pinMode(n, OUTPUT); statement in setup?  the behavior you describe is typical of leaving that out, in which case writing HIGH enables the internal pull-up resistor (about 30k[ch937]; very weak.)

baum


CrossRoads

And you have a 330ohm or so current limit resister in series with your LED also so you don't damage the output?
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

baum


Go Up