[Lazarus] Raspberry Pi Debug Digital I/O

[Marc Santhoff]

On Mo, 2016-01-25 at 08:33 +0100, Bo Berglund wrote:
> On Mon, 25 Jan 2016 00:18:50 +0100, Marc Santhoff <M.Santhoff at web.de>
> wrote:
> 
> >> For me it is like this:
> >> pi at rpi2-jessie2:~/dev $ cat /etc/group | grep gpio
> >> gpio:x:997:pi
> >
> >Thje last one wrong, should have been
> >
> >$ ls -lL /sys/class/gpio/gpiochip0
> 
> New test:
> 
> pi at rpi2-jessie2:~/dev $ ls -lL /sys/class/gpio/gpiochip0
> total 0
> -rwxrwx--- 1 root gpio 4096 Jan 17 16:47 base
> drwxr-xr-x 3 root root    0 Jan 17 16:47 device
> -rwxrwx--- 1 root gpio 4096 Jan 17 16:47 label
> -rwxrwx--- 1 root gpio 4096 Jan 17 16:47 ngpio
> drwxrwx--- 2 root gpio    0 Jan 17 16:47 subsystem
> -rwxrwx--- 1 root gpio 4096 Jan 17 16:47 uevent
> 
> >and
> >
> >$ ls -lL ../../devices/platform/soc/3f200000.gpio/gpio/
> 
> This is a relative path and you did not specify where one should be
> located in order to execute it. Cannot perform this command.
> Please supply an absolute path instead.

I know. The user can see from where links are not resolved by reading
the failing command. My point was to help diagnosing why a program
running as user pi did not work. I explained with the changed command,
for checking permissions on the targets of the links, not the links
themselves.

But since you found the cause by your patch differentiating between RPi1
and RPi2 it's obsolete now.

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