I/O board

Good evening all,

I am on the way of making a project showing that open source can be used for a lot of things in education.
And that you don’t always need S7, Danfoss…
The goal is to make a PLC with 8 digital inputs/outputs and analog input or I2C to read temperature/ humidity.

So I would need to make a cape which is connected to the GPIO’s of the BBB Rev A5C at startup and that starts-up a script at start-up.

On the web I have already found a lot of examples how to blink a LED or how to read the input.

Is there some guideline/project which could help me out a little bit concerning the hardware design (to make a cape)?

I would like to use optocouplers to connect directly to the GPIO pins.

For programming I would use Pybbio. Is this sufficient?

For the moment I am reading a lot of e-books on Python as I don’t have a lot experience with programming yet.

Thanks for your input, I will try to document the project online, so you can follow it.

Thanks in advance

Hi Bram,

I have recently designed an I/O cape for the BBB, had a prototype run of PCBs made, and built up two of them so far. The board has:
- 4 digital outputs (with LED indicators)
- 4 digital inputs (with LED indicators)
- 6 analogue inputs (somewhat configurable)
All the above are 5V tolerant but not optoisolated
- 12 more of the I/O pins are available on one header
- some of the special purpose lines available on another header (SPI, UART, etc)
- fitted with the specified EEPROM
- mix of surface mount and through hole - to make it easier to modify.

I have it working with a python driver and test program. Still trying to find time to finish off the project I originally designed it for but also wondering if there would be any interest out there for it.

Hey, that’s just what I want to make but opto-isolated.

Did you use I2C for your inputs/outputs or did you address each GPIO pin?

In my project each GPIO pin would be a input/output.

Do you have some documentation on what you have made?


See http://alanprojects.blogspot.com.au/2013/11/beagle-bone-black-general-io-board.html

Thanks Alan, I am sure this will help me