Sounds like the pin mode is not set correctly.There are multiple registers that need to be set. Setting up the pin mode and then setting up the pin mux to make sure the pin is connected to the actual pin on the processor..
Gerald On Tue, Dec 9, 2014 at 2:58 PM, Maxi Miller <[email protected]> wrote: > Both are connected to the same power outlet. > And why is the other BBB not reacting when changing the state? It always > stays at 1 (3.3V) even if I switch it off via command line... > > > Am Dienstag, 9. Dezember 2014 20:25:56 UTC+1 schrieb Gerald: >> >> Sounds like you have a grounding issue with your scope. Make sure the >> power and scope are connected to the same power outlet that the scope probe >> ground is connected to the board ground. >> >> Gerald >> >> >> On Tue, Dec 9, 2014 at 11:39 AM, Maxi Miller <[email protected]> >> wrote: >> >>> Hi, >>> I am running two BBBs via power adapter, and I wanted to test the GPIO >>> pins. One of them runs still on the manufacturing OS, the other one is >>> up-to-date. Now I wanted to see the GPIO pin values with an oscilloscope. >>> While trying to switch the pins on and off on the up-to-date-board via echo >>> on/off > <pin> I experienced that the pin I wanted to switch never changed >>> state. Therefore I tried to do the same on the other board, thinking that >>> it was a software fault. But there I only measured a 50Hz-triangular >>> signal, regardless which pin I chose (Even on GND and 5V). Why? What can I >>> do to bring both of them back to work? >>> Thanks! >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> Gerald >> >> [email protected] >> http://beagleboard.org/ >> http://circuitco.com/support/ >> > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- Gerald [email protected] http://beagleboard.org/ http://circuitco.com/support/ -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
