Just as an update I found out this can only be done with device trees.

On Thursday, November 21, 2013 10:26:07 AM UTC-6, [email protected] wrote:
>
> 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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