Sunday, November 20, 2011

More Bluetooth Single-wire CAN adapters!

Over the past week I built and tested two more Bluetooth single-wire CAN OBD adapters. These are the little blue ones from DealExtreme that, out of the box, work with everything except the GM single-wire network. This network is special for a few reasons:

1. Command and comfort - the network controls everything from the heated seats to the remote starter. 2. Many devices ("nodes") are present on this network and communicate interesting metrics to each other (which can be viewed relatively easily). 3. You can not only view data on the network, but you can send to the network. Using tools like libVoyager, developers can design software that executes commands (lock doors, unlock doors, engage the factory remote starter, turn on/off the heated seats, etc). So with a little imagination you can see why they are so popular.

What these adaptors do not do: 1. No OBD. They can't be used with your favorite OBD software... Not yet at least. 2. You shouldn't leave it plugged in while driving since they are still just prototypes, which means they could have bugs. 3. there is little or no software that utilizes the adapters yet. You basically have to be a developer that's doing your own testing. The adapter will get you connected with the Single-wire network but it's up to you how you harness that power :)

Sleuth (Android SWCAN App) is available on GitHub (open source) and currently has lock and unlock buttons as an example of how to use libVoyager. So if you're and Android programmer, that's where you may want to get started.

So if you want one for your own testing (remember no software really supports them yet), please contact me at, GTOSoft @

Friday, July 22, 2011

Single Wire CAN!

I built three more prototype SWCAN adapters and have posted them on eBay!

Improvements in the current design
- New upgraded microchip communicates more efficiently
- Updated circuit components - higher quality, smaller.
- Automatic wake-up of the network, so it should work even if the network is asleep!

This weekend I'm setting out to write a free Android app that communicates directly with SWCAN adapters. I'll have buttons for basics like lock/unlock/starter/radio controls. I think I'll re-use the name "VoyagerRC", since that's the one in our youtube videos, and the one we get the most fanmail for :)

Hopefully we'll ramp up the sale of these adapters so we can continue to improve the design. There is a lot of potential with the new prototype because of its ability to wake up the network. If you lock yourself out of your newer GM car, and have this plugged in, you can use your android phone to unlock the doors and get back in :)


Tuesday, June 28, 2011

How to make a SWCAN adapter

Here's what goes into a modified CAN adapter to make it SWCAN.

Finished product

Sandwich the boards together with sufficient insulation to prevent shorts.

Bottom side of the board. The SWCAN wire is shown extending out to the left.

Top of the board. Using a new solder tip and it had been a while, so don't hate :)

Another topside

Bill of materials

  • 1x Bluetooth OBD adapter with regular CAN support (uses MCP2551 CAN transceiver).
  • 1x 8056 SWCAN transceiver.
  • some small wires (I cut open a USB cable to get the thin green and white wires shown).
  • Discrete parts list from (this is the BOM that I order to make more of these).
  • Electroboards SOIC-8 breakout-board. These are about $1 each. Highly recommended.

Sleuth - IS VoyagerRC

Sleuth is a work in progress, like anything else. But as it stands now, it is wired to send commands to the SWCAN bus... assuming you're using a SWCAN modified adapter. If you don't have one, I sell them for $100 each but with no warranty because they are for testing only. I use them with no problem on my car.

The third button you will see on the screenshot below is a "wake up". It actually wakes up the network using some advanced signaling that I built into my latest SWCAN adapter. That means it is able to wake up the car network and send commands, regardless of whether the car is on/off or in between :)

Thursday, June 16, 2011

Writers Block

I have a bit of writers block - any suggestions for what code to write next? :)

I've been committing gobs of code to the libvoyager project so anybody who's interested, check it out! I just added some code to support a new protocol called SVIP - Simple Vehicle Interface Protocol. It will bridge carputer style apps, to their user, anywhere in the world!

LinkSend your suggestions in email or as a comment to this post! I hope to spend lots of time this weekend converting coffee into code ;-)


Wednesday, May 11, 2011

Ready to compile

As you know, libvoyager has been released open source. To provide examples of its usage, I also included a new project we started, called Sleuth. Sleuth connects to the closest ELM OBDII sensor, detects the network, and proceeds to show various information about the car network. All of which is passive and completely harmless. I'll continue to work on Sleuth to improve it and add features. During this time I'll tweak and improve libvoyager.

If you have any specific requests or ideas, please feel free to share. Better yet, download the project and let's build it together!


Monday, May 9, 2011

libVoyager is now Open Source!

We did it! libvoyager has been released open-source! We also included Sleuth, a new CAN/OBD network analyzer (built on libvoyager) to help programmers get up to speed and start contributing sooner to the project.

Please download it, check it out, and by all means - contribute!!! =) In the next few months we hope to see this project grow faster and bigger than anything like it.