Raspberry pi 3 GPIO not working

Question

I am currently trying to turn an LED off but it is not working. (LED is always on, yes I do have a resistor 220 ohm) I have Wiringpi installed and looking at the readall data I do not see any change when I run my commands. I have tried directly in the python program, creating a python script and running it, running python from terminal, and using the wiringpi gpio commands. I have also tried doing all of this with sudo as well. import RPi.GPIO as gpio
gpio.setmode(gpio.BCM)
gpio.setup(17, gpio.OUT)
gpio.output(17, False)

rew · Accepted Answer

Wait!.... As far as I know there are two numbering schemes. NEITHER uses the pin number on the connector. Can you try "sudo apt-get install wiringpi" and then "gpio readall". That should give you an overview of what is currently configured. As bcm pin 17 is listed as wiring pi pin number zero, I would then test: gpio mode 0 OUT and verify that something changed by using gpio readall again. I just did that for you on my pi and I see: | 17 | 0 | GPIO. 0 | IN | 0 | 11 || 12 | 0 | IN | GPIO. 1 | 1 | 18 | changed into: | 17 | 0 | GPIO. 0 | OUT | 0 | 11 || 12 | 0 | IN | GPIO. 1 | 1 | 18 | Now, on my pi the led would be off, as the output value is low, but gpio write 0 1 would turn it on: | 17 | 0 | GPIO. 0 | OUT | 1 | 11 || 12 | 0 | IN | GPIO. 1 | 1 | 18 | This eliminates possible errors with you interacting with the python, and verifies the hardware. Worst case you've already blown up that GPIO output of the pi with some earlier experiment..... Another theory.... Could it be that you have the cable between the pi and the breadboard inverted? The side of the cable with the red pin goes FURTHEST away from the USB and ethernet connectors.

byrd · Answer

The ribbon cable was inverted..... Wow that's completely my fault for not reading the instructions clear enough, I just went back and read them and it says which side should be where. Thank you all for pitching in to help me! This was my first post on this site and the responses were quick and helpful. I'll be sticking around here for a while!