Project Hardware Wrap Redux

So close…

vehicle debug

mid debug


I hit another snag with respect to my IOIO specs butting heads with actual power yield. An early success:

…followed by being unable to replicate via battery control, despite higher voltage. I might be running into a similar incident that I saw when putting together the PowerSwitch Tail project. I’ll get there…might have resisters coming out the ass, but I should be able to solve this issue with a creative open-drain setup as well. Tune in again…

IOIO PowerSwitch Project

I can finally report a conclusion of sorts on the IOIO / PowerSwitch Tail project. The ‘of sorts’ disclaimer is in regards to my Android App, which is pretty much a working beta. I have some issues with my onResume code, and want to put some polish on the UI. That said, I have released the code to the interwebs, so had better provide a write-up.

The setup is the same as I have been posting. Dual open drain pins with a 10K pull to 5V do the lifting…triggering of pins is handled via my IOIO board…Android app providing a UI to do the switching.

ioio-example-project

beta version: check.

I went ahead and published my app on the Android Market. It will pop for sure by searching for IOIO.

android market app

apptastic

Price: free ninety nine. Can’t beat that.

I also tossed this code up on GitHub. Go nuts.

github example

/swantron

Video time: see this in action.

Basically, between all of the shaky camera work, I download my app from the Android Market, connect via USB, and control the 120V relay via my Droid 2. I will shoot a better video once I clean up my code a bit.

Stay tuned. The README on GitHub and the app details section should have all of the connection information. I can provide any further details via email / comments / @swantron. Have fun with this one…

Link to android market
Link to project code at GitHub

Blown Multimeter

So, good news and bad news. Yin and Yang.

I managed to get my open drain setup working with the IOIO. Ytai was right…just needed to dump more current through the sucker and pull 5V from the board. See below:

pull up

pulling up to 5V

On to the bad. I wasn’t pushing enough current to trigger my 120V relay…but before I could do some current calculations, my piece of shit Radio Shack multimeter finally gave out. How timely?

Not to worry…a quick trip to Lowes, and we have a new (much higher quality) Ideal DMM:

ideal multimeter

+1 thermocouple

Your eyes aren’t fooling you…that is a thermocouple. Thermocouple and stand…pretty official.

I’ll get some calculations done and figure out where we are with this guy…pretty close!

Open Drain Example IOIO Android

Hi.

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…