Looking good!! Thanks for sharing pictures, I love seeing what people do with the CBT!
The way I identify the best place to MITM is as close to the actual device I want to control as possible. Every car is different so a little trial and error will be involved. The nice thing is if it does not work you can just reconnect the cut bus and it will still work.
Also you'll want to tap in somewhere where the CBT will have to send/receive as few packets as possible to achieve the desired effect.That assures it can read process and resend the CAN data fast.
I'd love to continue making these but I have to order a thousand minimum to make them are a reasonable price. And it's a ton of labor on my part to assemble them. I did over a thousand by hand, it sucked and I would rather spend that time on support and future hardware.
Indeed, it works I keep my CBT plugged into my Mazda even tho I wont drive it for weeks at a time. You just need to enable the 'Naptime' middleware.
In a lot of cars you will find a kind of heartbeat message. It's dispatched maybe once a second while the car is on. You can pass this message id into the middleware and it will automatically go to sleep when it does not see it for a while. It also sets a filter on the CAN controller that will trigger an interrupt to wake the system back up when it does receive the heartbeat message.
Here you will see it's enabled by setting a C def:
You can just uncomment the def on line 16 to enable the Naptime middleware. And be sure to set a heartbeat message id on line 56 or set it to 0x0000.
I had a thread about this and it seems to be gone. Weird!
So a simplified way to add the CBT support to your Arduino installation is by adding this custom URL to your settings and installing the lib via the Boards Manager.
Load up Arduino and head to Preferences. Then in the field marked "Additional Boards Manager URLs" add this URL:
Press ok to close the window.
Then go to Tools > Board > Boards Manager
In the filter just type CANBus and you should see the CANBus Triple library. Click install and you're good to go!