GPIO pins (again)


I have been all over the forums and cannot find a consistent answer on which pins are available/unavailable. The pinout page in the docs is very confusing and I do not want to fry anything. Which pins are not being used? And how can I access these pins because of the tops of them are unavailable. I see that I may need to use a shim board to physically get to these suckers. In addition, I cannot use the UART pins because I have a telemetry link installed. I am using a Navio2 with a Raspberry Pi 3B.

If I2C is the only way to connect additional sensors (like:, could someone please post a tutorial or some other reference.


Hi Robert,

I’m currently using a USB to TTY serial adapter and had great results so far. I’m my case I wanted to use an external GPS/compass which took up the UART and I2C ports on the Navio 2, but I still required use of the OSD and telemetry. This little cable did the trick :slight_smile:

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@Robert_Brown GPIO17 and GPIO18 are available for usage. Even if you can’t access them in the UART port you still can use them. You can solder to their points on the bottom side of the RPi. Alternatively you can buy a header with longer pins to be able to access them from the top.

Can you please provide confirmation that GPIO Pins 17 & 18 are definitely not being used? By the Navio2 board?

As the Pinout diagram is not clear currently showing GPIO17_DF13 and GPIO18_DF18


Hey there!

Here DF13 stands for the connector type used on Navio boards. You can flip over your board and see 2 spare pins on UART connected that are labeled as IO17 and IO18.

We’ll try to make pinout diagram a little more transparent.