Fixed GPIO export problem; Leaves GPIO in bad state on latest BeagleB…

[erikwelsh]

This pull request fixes issue #281

This is a quick copy of the LED detection code from gpio_set_direction into the gpio_export() function.

[pdp7]

@erikwelsh thanks for creating this PR.

I will test this out and merge if no issues.

[pdp7]

I was able to test this successfully on BeagleBone Blue and turn on and off all 4 USR LEDs, in addition to the other built-in LEDs.

import Adafruit_BBIO.GPIO as GPIO
import time

# test built in LEDs on BeagleBone Blue
LED =  [ "USR0" , "USR1", "USR2", "USR3", "RED_LED", "GREEN_LED", "BAT25", "BAT50", "BAT75", "BAT100", "WIFI" ]

for i in LED:
	print("{0}: setup".format(i))
	GPIO.setup(i, GPIO.OUT)

while True:
	for i in LED:
		print("{0}: on".format(i))
		GPIO.output(i, GPIO.HIGH)
		time.sleep(0.5)
		print("{0}: off".format(i))
		GPIO.output(i, GPIO.LOW)
		time.sleep(0.5)