[0.0.5 b251] gpio8 vs others

[François Levaux]

Since updating to 0.0.5 b251, I lost all my GPIO's but gpio8 in /sys/class/gpio/
Is this expected?

Also, gpio8 still has no support of 'direction'.
See https://community.onion.io/topic/40/simple-python-wrapper-and-demo from @dan-l

[François Levaux]

So it's more interesting than I thought originally.

When upgrading system to b251, it overwrote /etc/config/fstab, which is documented in https://community.onion.io/topic/362/0-0-5-b251-etc-config-fstab-not-persistent

Then I didn't knew I had to export my GPIOs to get them on sysfs.
interesting thing is that I had only /sys/class/gpio/gpio8 present.

Perhaps someone messed something with gpio8 ?

root@Omega-15B0:~# echo 8 > /sys/class/gpio/export 
ash: write error: Device or resource busy
root@Omega-15B0:~# echo 8 > /sys/class/gpio/unexport 
ash: write error: Invalid argument
root@Omega-15B0:~# 

[Boken Lin]

Hi @François-Levaux, GPIO 8 is used by the Omega as the power LED (the LED that flashes on boot and then becomes solid). So it has no support for direction because it is only used for output.

[François Levaux]

Thanks @Boken-Lin -- It makes more sense.
My understanding from https://wiki.onion.io/Tutorials/Using-the-GPIOs is that it's a standard GPIO. Would you need to update this diagram?

[Matthias Dietrich]

According to @Lazar-Demin (here: http://community.onion.io/topic/395/gpio-pin-12/4) GPIO27 is used for controlling the power LED and GPIO8 "is wacky". Didn't find some update on the GPIO8 (and GPIO12: http://community.onion.io/topic/578/issue-with-gpio-12/12) issue.

[Kit Bishop]

@Matthias-Dietrich Yes See my latest response to https://community.onion.io/topic/578/issue-with-gpio-12/14