using wiringPi2-python (non root) segmentation fault catching for GPIO

问题

i'm using wiringPi2-python to switch a raspberry GPIO pin from low to high and back. Everything works BUT right after it switches the pin's value a Segmentation fault is thrown and the program stops.
I need to use this approach because this seems to be the only way to access the GPIO pins without sudo

before starting the program i need to setup the pins to output and export them so:

$ echo 17 > /sys/class/gpio/export
$ echo out > /sys/class/gpio/gpio17/direction

and then a bit of python shell:

$ python
Python 2.7.3 (default, Jan 13 2013, 11:20:46) 
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import wiringpi2 as pi
>>> pi.wiringPiSetupSys()
0
>>> pi.digitalWrite(17, 1)
Segmentation fault
$

i tried this approach, but it wasn't any better. The program still stopped.:

try:
        pi.digitalWrite(17, 0)
except:
        print('got an error')
print('just printing something to see if gets to end')

So my question is how can i catch the error properly, so i could just ignore it because the code actually works.
Ps: This is propably worth a bug report but i want to get my head around it first.

回答1:

so i figured it out. i need to make another process for digitalwrite. In that case the newly created process stops but the rest of the program can continue working.

import wiringpi2 as pi
from multiprocessing import Process

def process(choice):
        if choice == "1":
                pi.digitalWrite(17, 1)
        else:
                pi.digitalWrite(17, 0)

if __name__ == '__main__':
        pi.wiringPiSetupSys()
        choice = raw_input(">")
        p = Process(target=process, args=(choice,))
        p.start()
        p.join()

print('just printing something to see if gets to end')

来源：https://stackoverflow.com/questions/20828758/using-wiringpi2-python-non-root-segmentation-fault-catching-for-gpio

标签

python

raspberry-pi

gpio