Raspberry Pi Stack Exchange is a question and answer site for users and developers of hardware and software for Raspberry Pi. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

So, just to try and keep the wheezy up to date I did an apt-get dist-upgrade and upgraded a couple of things, among which python.

Now, when I try runing the example ./Adafruit_CharLCD.py I get no output to my mini LCD screen, which before the update all was going great.

I don't get any kind of error besides the same one as before

./Adafruit_CharLCD.py:68: RuntimeWarning: This channel is already in use, continuing anyway. Use GPIO.setwarnings(False) ....

Any ideas what could go wrong, or any way of debugging why doesn't it output nothing?

share|improve this question
up vote 0 down vote accepted

The issue was in the Adafruit_CharLCD.py file, where having the following line

def __init__(self, pin_rs=25, pin_e=24, pin_db=[23,17,21, 22], GPIO = None):

which in the previous version (note that this was the first time that I ever started working with RaspberryPi, and, Adafruit LCD) the pin_db set, by another person, to [23, 17, 27, 22]

more details here: http://learn.adafruit.com/drive-a-16x2-lcd-directly-with-a-raspberry-pi/python-code

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.