Raspberry Can't Access /dev/mem

I have installed Raspbian on my Raspberry and added in: /etc/rc.local: chown /dev/ttyUSB0 #to allow current user to use 3G modem /etc/sudoers: raspbian ALL=NOPASSWD: ALL And f

Solution 1:

I found the problem.

I forgot about:

  GPIO.setup(<PIN>, <MODE>)

And without this Python throws and exception where write to try to run code with root.