![rss menu missing ip.board rss menu missing ip.board](http://www.pd0zry.nl/galleries/MTR2000/system_connector3.jpg)
GPIO (gpio-sunxi), SPI (spi-sunxi), and I2C (i2c-sunxi) drivers are pre-installed in the Debian Jessie image I installed in Orange Pi 2 mini board, but today, I only played with GPIO on my board. this came up whilst working offshore recently, a discussion took place regarding a failed Ex inspection of a pressure transmitter due to a missing IP washer, the equipment in question was a rosemount pressure transmitter fed with an IS circuit, the instrument was rated Exia 11c T6 IP 66/67 and was in Zone 2. So instead I used sysfs to control the board’s I/Os. Banana Pro is based on Allwinner A20, so some registers and addresses might be different, but required technical information should be available in Allwinner H3 datasheet. If somebody is interested in working on a GPIO library for Orange Pi, starting with LeMaker’s WiringBP for Banana Pro might be a good idea, as GPIO, SPI and I2C support is implemented. After cheking in the forums, it seems there’s no GPIO library for Orange Pi boards. A more generic GPIO page refers to RPi.GPIO, BCM2835 and WebioPi libraries, but again those sections are empty. Some documentation would be nice too, and there’s a WiringPi for Orange Pi page in the wiki, which points to WiringOP on github, but unfortunately it does not exist. Orange Pi PC is a little different, and the schematics are nowhere to be found, but it would be surprising if the 40-pin connector had a different layout. I downloaded the schematics for Orange Pi 2, which should be the same as for Orange Pi 2 mini as the only difference is the lack of WiFi module.
![rss menu missing ip.board rss menu missing ip.board](https://i.gyazo.com/b66c6b88121b38b8505c4a754d380c67.png)
![rss menu missing ip.board rss menu missing ip.board](https://cdn.shopify.com/s/files/1/0501/6915/1656/files/Screen_Shot_2020-10-31_at_1.04.27_PM_505551c4-45f7-4696-9984-b950d8e4182c_1200x1200.png)
One of the first things you want before starting playing with GPIOs is the expansion header’s pinout chart, and I could not find any until I had the idea to check for schematics, which are available on Orange Pi resources page. This post focuses on Allwinner H3 boards, but the instructions and status should be very similar for Allwinner A20 and A31s versions. Yesterday, one person asked me to make a video showing GPIO control on Orange Pi 2 mini on YouTube, and since I have just completed a post about Orange Pi camera, I thought it might be fun to check GPIO support too.