Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: bremenpl on March 03, 2015, 02:10:46 PM

Title: SOM-A20 gpio tutorial
Post by: bremenpl on March 03, 2015, 02:10:46 PM
Hello there,
So far I was working only with BeagleBone Black when it comes to embedded linux. I have a SOM-A20 board now and I was wondering how to interface with the gpio's without sys/fs. I also couldnt find any refference to tree overlays, is it only BeagleBone Black specific functionality? I would really aprichiate if someone could point me out some A20 gpio tutorial as I couldnt find anything usefull so far.
Title: Re: SOM-A20 gpio tutorial
Post by: JohnS on March 03, 2015, 03:27:29 PM
DT (device tree) is in development for AW boards

AW use FEX instead

John
Title: Re: SOM-A20 gpio tutorial
Post by: bremenpl on March 03, 2015, 03:29:15 PM
Are there any tutorials for that, maybe by olimex?
Title: Re: SOM-A20 gpio tutorial
Post by: JohnS on March 03, 2015, 03:33:36 PM
I doubt Olimex would as they're a hardware maker and anyway I doubt a tutorial can exist for something not yet done or did you mean something else?  BTW, if it's not on google it doesn't exist :)

At a guess there will be something in months.

John
Title: Re: SOM-A20 gpio tutorial
Post by: bremenpl on March 03, 2015, 03:34:48 PM
I meant some tutorial for FEX. I tried to find it but it seems to be a hipster thing as I couldnd find anything specific.
Title: Re: SOM-A20 gpio tutorial
Post by: JohnS on March 03, 2015, 03:37:06 PM
It's obsolete so use it only if you understand that.

linux-sunxi.org/Fex_Guide

John
Title: Re: SOM-A20 gpio tutorial
Post by: bremenpl on March 03, 2015, 03:48:54 PM
hardly a tutorial, but thank you :P.
Title: Re: SOM-A20 gpio tutorial
Post by: JohnS on March 03, 2015, 05:21:15 PM
Then use sysfs etc!

http://lmgtfy.com/?q=%22fex%22+guide+OR+tutorial
http://lmgtfy.com/?q=olimex+%22fex%22+guide+OR+tutorial

John
Title: Re: SOM-A20 gpio tutorial
Post by: deskwizard on March 03, 2015, 05:32:51 PM
this could also be useful

https://www.olimex.com/forum/index.php?topic=1514.15 (https://www.olimex.com/forum/index.php?topic=1514.15)
Title: Re: SOM-A20 gpio tutorial
Post by: kantal on March 03, 2015, 08:11:17 PM
Hi!

You can use mmapped based GPIO access with Linux.