Wednesday, June 5, 2013

Conquering the Dexcom API's and Shopping for Watches

I've made great progress with finding what to call in the Dexcom DLL's.  7 lines of code and I can get an XML document with everything on the receiver in it.  This works great from Windows.

Now the hard part.  I've figured out how to parse the raw serial data coming out of the Dex.  This should allow me to port this over to Linux without needing the Dexcom DLL's.   A rainy weekend is forecast, so I'll be trying to communicate with the Dex from the Raspberry PI.  I've already confirmed the PI will talk to the TI Watch without issue.

Now that I'm getting close, I'm getting greedy.  The TI Watch will work perfectly for my hazardous duty requirements, but it only has a transmit range of 10 feet or so.  The Dexcom will go to 20 feet.  I think I might have to look into the MetaWatch, water resistant and capable of greater distance with bluetooth.

I'm trying to avoid having to network with a Smart Phone though.  I don't want to have to pay for Hotspot features, nor do I want to be dependent on cell phone access.


  1. Godspeed good sir. I am planning on investing in a CGM (likely a Dexcom product) and plan on hacking around with it as well.

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  3. This is great. It sounds like I'm going through a similar process (I've captured the usb traffic during a dexcom studio data transfer). Reading through the comments here, it sounds like a lot of people are trying to do the same on their end. It would be nice to have a nicely wrapped open source library that reads the data from the dexcom receiver via usb and it sounds like you could kickstart such an effort.

    My personal goal would be to make a Mac data reader/uploader. I'd use that data for another app I'm working on.

    If you're interested in contributing your work so far, I'd say it doesn't have to be totally finished. I could definitely grab something that still needs work and work on the polish.

    Great work. Inspiring. Cheers!

  4. I'd love to see an OSS library as well. If not that, I'd really appreciate hearing how to get data back from the G4. I know it's just basically a usb/serial adapter, but no clue what commands to send.

    I suppose I could just sniff the usb or serial traffic, but I figured I'd ask.

    1. Post your email address to me via: And I'll send the code to you.

  5. Hi. I tried to use your contact form (twice), but it generates an error code. I am interested in the code you've come up with.