Hello Everyone,

I have a question regarding input detection on BBB GPIO. I am working to 
switch from using Raspberry Pi to the BBB. I'm running into issues when it 
comes to reading inputs.

On both devices I can:

sudo su  //become root
cd /sys/class/gpio
echo "GPIONumber" >> export //create directory to work with GPIO pin
cd gpio<number>  
echo  "in"  >>  direction //set to detect input
cat  value //determine the current input

On the Raspberry Pi by default I get a value of "0" when nothing is 
connected to that port.
With the BBB by default I get a value of "1" when nothing is connected.

If I connect the Raspberry Pi to the +3.3v line I get a "1", and the BBB if 
I ground the port I get a "0". 

After Googling around the web I found that the Raspberry Pi GPIO is set to 
pulldown and the BBB is set to pullup. 

Is there a way to easy set the GPIO pins to pulldown on the BBB (not using 
bonescript). The only tutorials I can find have to do with 
/sys/kernal/omap_mux....

I am assuming that I am going to have to work with the device tree 
(something I've been avoiding). Is there a way to do this without touching 
the device tree? If not, does anyone have an example how to do this. I will 
continue to research how to work with the device tree but any guidance on 
how to accomplish switching the GPIO input settings from pullup to pulldown 
would be greatly appreciated.

Thanks!

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