May 27, 2018

Orange PI - the IO connector

The Orange Pi boards have a 40 pin IO connector. The diagram below shows a typical H3 board and will help to identify pin 1 on the connector.

The following diagram shows the pinout for the 40 pin connector. I count 28 GPIO pins if special functions are not selected. Table 3-2 on pages 74 to 77 of the H3 datasheet show the pin multiplexor business. It seems to go like this:

0 - GPIO input (the default)
1 - GPIO output
2 - special function as shown below
3 - alternate special function
6 - external interrupt
7 - disable

If you get tired of counting pin numbers on the above nice diagram, the following will help avoid silly mistakes:

Amazingly, the data sheet states (or seems to) that IO pins can source or sink up to 40 mA. See page 607 of the datasheet, table 9-1.

Orange Pi versus Raspberry Pi

I have not looked at this in detail, nor have I made any attempt to use expansion boards designed for the Rpi on the Opi. Power and ground are in the same location, which is promising. It at least means that things won't catch fire immediately.

It won't be immediately disastrous or hopeless. I won't say more. There would certainly be significant driver issues. Procede with caution and dig deep before trying anything along these lines.

The following diagram is for the IO connector on a "Orange Pi 2 (mini)" taken from the above article.

The following diagram is for the 40 pin connector on a Raspberry Pi. Note that older Raspi's used a 26 pin connector.


Have any comments? Questions? Drop me a line!

Tom's electronics pages / tom@mmto.org