GPIO setup correctly, no output


6 posts
by joepshoulak » Mon Apr 29, 2013 6:54 pm
So I connected pin 17 (GPIO 11) to one terminal of a motor, and pin 6 (GND) to the other pin, and when I sent the command for output to be sent to that pin (True, 1, HIGH, whatever...), nothing happened. I was, however, able to drive the motor off pins 2 (5v) and 6 (GND) and pins 1 (3.3v) and 6 (GND), but not off the GPIO pin. I got no error, and I tried it using Python, Ruby, C++, and just straight up Bash commands. Nothing worked.

My wires are good, my breadboard is good, my code is good, my motor is good, what am I missing?

:?:
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by techpaul » Mon Apr 29, 2013 6:59 pm
If you want to fry your Pi carry on.

The GPIO pin is a low power on / off switch, not a motor power supply.

You need to add proper motor control serach for motor controllers and other motor driving subjects in the search box or from places like google.

Your motor is wanting at least 100's mA and nasty back EMF when stopping, a GPIO output cannot supply more than about 16mA.
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by rpdom » Mon Apr 29, 2013 7:08 pm
joepshoulak wrote:So I connected pin 17 (GPIO 11)


I presume you mean pin 11 (GPIO 17)?

Even so, techpaul is right. You need a proper motor drive circuit, otherwise you may kill that GPIO pin by overcurrent.
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by joepshoulak » Tue Apr 30, 2013 7:09 pm
Is it possible for a single pin to burn out, or will it burn out the entire chip?
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by techpaul » Tue Apr 30, 2013 7:12 pm
Yes you could blow one pin depends on how it failed.
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by scotty101 » Tue Apr 30, 2013 7:19 pm
May I suggest that you do some research before you connect anything up to your raspberry pi.

I have found that the Adafruit tutorials are excellent and suitable for beginners

http://learn.adafruit.com/category/raspberry-pi
Building a Raspberry Pi Home. https://plus.google.com/100752687760844230040/posts/RtZzoVqDGfy
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