I2C with the DisplayOtron 3000


I have a DOT3k installed on a Raspberry Pi B (26-pin GPIO). I’d like to also interface to a Temp/Hum/Baro I2C sensor. I was hoping there would be some kind of I2C pass-thru on the DOT3k but don’t see one. Is there an elegant way to get I2C pins out of the DOT3k, or a breakout board that will allow me to access it? I like the compact fit of the DOT3k directly on the Rpi, so would prefer to leave it mounted that way.


DoT3K / Pi2 coupe (B+?)

You want to get yourself one of these babies. http://shop.pimoroni.com/products/black-hat-hacker It’ll let you access all of the GPIO pins but you’ll have to have the DOT3k mounted on the Black HAT Hack3r.


No problems using that on a 26pin GPIO instead of the 40pin one?


No problems at all! And you should, indeed, be able to solder pins into the middle test points and use it to break out i2c.

If you’re brave and in possession of a soldering iron, it probably wouldn’t be too hard to tack a couple of wires onto the i2c pins of dot3k’s header. It wouldn’t look great though and I’d say that Black HAT Hack3r is the easiest solution.

The third alternate, and also somewhat hacky, is to solder onto those pins underneath your Pi. I’ve been known to solder female headers to the underside of my Pi for getting to things like serial, i2c, etc. It’s not a pretty mod, nor an easy one, but it’s really useful if you’re reckless/brave enough to try it.