Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A64 => Topic started by: HarrisonCreates on November 16, 2019, 08:34:36 PM

Title: Starting with GPIO
Post by: HarrisonCreates on November 16, 2019, 08:34:36 PM
Hello everybody!

I tried to go to the Wiki Page on the A64 to learn more about GPIO usage, pinouts, etc, but I can't seem to find anything. The closest GPIO related content I was able to digest for the A64 was the PyPi library for controlling them.

So I have a few questions; if these were answered already in this forum please notify me, since I did search through as well before posting.

Here's What I'm Trying to do: I want to run an Olimex vibration motor from GPIO when the touchscreen is interacted with. I already wrote code to detect a touchscreen interaction which maps to a python endpoint, which would then trigger the GPIO. But I need to know how to wire to the GPIO pins before I can code for them.

So my questions are these:

1.) Which pin is the GPIO ground pin?
2.) Is there overvoltage protection? What is the max voltage/current that can be provided by a GPIO pin?
3.) How many analog/digital GPIO pins are there?
4.) Is there a pinout available to reference?

Thank you everybody! I really tried to find online resources for this but I wasn't able to find anything. YouTube tutorials, Olimex Wiki, A64 forum, etc.
Title: Re: Starting with GPIO
Post by: HarrisonCreates on November 21, 2019, 11:15:09 PM
Would anyone like to help out with this question?
Title: Re: Starting with GPIO
Post by: martinayotte on November 22, 2019, 04:30:19 PM
1) Any GND pins found on the header.
2) No protection.
3) No analog, only digital, the ones that are available on the header
4) Look at the schematic :
https://github.com/OLIMEX/OLINUXINO/raw/master/HARDWARE/A64-OLinuXino/1.%20Latest%20hardware%20revision/A64-OLinuXino%20hardware%20revision%20E/A64-OlinuXino_Rev_E.pdf (https://github.com/OLIMEX/OLINUXINO/raw/master/HARDWARE/A64-OLinuXino/1.%20Latest%20hardware%20revision/A64-OLinuXino%20hardware%20revision%20E/A64-OlinuXino_Rev_E.pdf)
Title: Re: Starting with GPIO
Post by: JohnS on November 22, 2019, 06:53:13 PM
2. No protection. Datasheet has the limits.  Be aware that max values include such meanings as "summed across all pins" and may require heat sink / fan / etc.  If you want reliability do not get near the max for anything.

John
Title: Re: Starting with GPIO
Post by: HarrisonCreates on November 23, 2019, 03:30:38 AM
Quote from: martinayotte on November 22, 2019, 04:30:19 PM1) Any GND pins found on the header.
2) No protection.
3) No analog, only digital, the ones that are available on the header
4) Look at the schematic :
https://github.com/OLIMEX/OLINUXINO/raw/master/HARDWARE/A64-OLinuXino/1.%20Latest%20hardware%20revision/A64-OLinuXino%20hardware%20revision%20E/A64-OlinuXino_Rev_E.pdf (https://github.com/OLIMEX/OLINUXINO/raw/master/HARDWARE/A64-OLinuXino/1.%20Latest%20hardware%20revision/A64-OLinuXino%20hardware%20revision%20E/A64-OlinuXino_Rev_E.pdf)

Thank you so much! I really appreciate it :D