Open Drain Example IOIO Android


This project never ends.

I have been cutting my teeth on some electrical engineering 101, in an effort to push 5V through my IOIO. At this point, I am still not able to report a success.

I do have the ‘open drain’ setup working, at a lower voltage than I am intending. My configuration is as follows:

pull up resistor

pulling up to 5V

The Java snippet that is doing the pin defining is this guy:

DigitalOutput out = ioio.openDigitalOutput(25, DigitalOutput.Spec.Mode.OPEN_DRAIN, true);

The only issue is with my setup…for some reason, my circuit isn’t able to pull to 5V. See the DMM readout v

almost there

so close...

So, back to the drawing board. When the switch is open via my app, the pull up resister should settle Vout to 5V. The other half of the scenario is fully functional, as a closed switch grounds as intended.

My next plan of attack involves a more permanent power source, and I have placed my order with SparkFun for a surface mount / wall wart combo that will do the trick. I am hoping that my issue is with the power, but time will (shortly) tell if this is the case.

Stay tuned. Getting close on this one…

4 thoughts on “Open Drain Example IOIO Android

  1. The ioio-users list is your friend! Many people there might be able to help you.
    For your specific problem: what you’re describing is supposed to work (open-drain with 5V on pin 25 works for me). Where are you getting the 5V from? Is it from the 5V line on the IOIO?

  2. Thanks for stopping by Ytai…your are my new inventor-guy hero for sure! I have tried to pull 5V both from the IOIO line out and externally. I should have my power adapter in the mailbox today, so will give that a shot and see if I can get my levels up. If not, expect to see a question to the user group. Take care.

  3. very cool. post the full project w/ some code

  4. I liked your article is an interesting technology
    thanks to google I found you