Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: filmacu on December 20, 2022, 05:07:04 PM

Title: A20 Olinuxino changing GPIO MUX
Post by: filmacu on December 20, 2022, 05:07:04 PM
So we have used the A20 Olinuxino for many years, previously using Debian Wheezy. I have just started using the very latest (2022) image which now runs Bullseye. All is going well except for one area. Under Wheezy we could change the gpio pin mapping via sunxi-tools.
mount /dev/mmcblk0p1 /mnt/mmc
cd /mnt/mmc
# now make the sunxi tools available to any directory
export PATH=$PATH:/opt/sunxi-tools
bin2fex script.bin > script.fex
nano script.fex

Once done I could edit the mapping and make available different GPIO to the image.
I have found the location of sunxi-tools in the new 'Bullseye' image, but I can't find the script.bin that describes the default mapping. Any help on locating this would be appreciated.

The reason that I need to change the mapping is that on 'Bullesye' bringing Pin13 of GPIO Con 3 low seems to cause the Ethernet to reset. This is not an issue on the original 'Wheezy' image.
Title: Re: A20 Olinuxino changing GPIO MUX
Post by: LubOlimex on December 21, 2022, 12:38:59 PM
There is no script.bin and script.fex to change pin assignments in mainline images. The new images uses dts and overlays for this. I guess you can make own overlays with pinout. You can find such scripts here:

https://github.com/OLIMEX/olinuxino-overlays/tree/master/sun7i-a20

Also before you dive into the deep explore the olinuxino-overlay and the olinuxino-display scripts.
Title: Re: A20 Olinuxino changing GPIO MUX
Post by: filmacu on December 21, 2022, 03:33:56 PM
Thanks for the reply
A) At least I can stop looking for script.bin  ;)
B) I will have a look at creating our own Overlay

phil