[Lazarus] Raspberry Pi Debug Digital I/O

[Marc Santhoff]

On So, 2016-01-24 at 20:59 +0100, Koenraad Lelong wrote:

> When I run the application as 'pi', I get this :
> 
> root at raspberrypi:/home/pi/Documents/lazarus/pascalio/koen-test# ls -l 
> /sys/class/gpio
> totaal 0
> -rwxrwx--- 1 root gpio 4096 jan 22 22:03 export
> lrwxrwxrwx 1 root gpio    0 jan 24 19:43 gpio17 -> 
> ../../devices/platform/soc/3f200000.gpio/gpio/gpio17
> lrwxrwxrwx 1 root gpio    0 jan 24 19:43 gpio18 -> 
> ../../devices/platform/soc/3f200000.gpio/gpio/gpio18
> lrwxrwxrwx 1 root gpio    0 jan 22 22:03 gpiochip0 -> 
> ../../devices/platform/soc/3f200000.gpio/gpio/gpiochip0
> -rwxrwx--- 1 root gpio 4096 jan 22 22:03 unexport
> root at raspberrypi:/home/pi/Documents/lazarus/pascalio/koen-test#
> 
> But the IO does not work. When I do
> echo 1 > /sys/class/gpio/gpio17/value
> from the command-line, the IO does not work, even when I do this as root.
> 
> When I run the application as root, everything works as expected.

What do

$ cat /etc/group | grep gpio

and

$ ls -lL /sys/class/gpio

show?

-- 
Marc Santhoff <M.Santhoff at web.de>