If the CAN bus used in automobiles is affordable it might be a great way to control sensors and s...

[G+_Rud Dog]

If the CAN bus used in automobiles is affordable it might be a great way to control sensors and switches around the home. It appears to have a decent distance the signal will travel. Just started reading up on this and would love to hear any comments for its limitations.

[G+_Chris Eckeard (StMerlin]

Interesting idea using it for the home. Signal is boosted along from module to module in car so the same should hold true for the home making transmission distance very manageable. Benefit would be reliability but Huge draw back is implimintation in that it involves wires. ? Fiber can also be used for transmitting the CAN protocol but I don't know if that would offer current day benefits.

[G+_Black Merc]

I see one problem..."The High-Speed ISO 11898 Standard specifications are given for a maximum signaling rate of 1 Mbps

with a bus length of 40 m with a maximum of 30 nodes." quoted from Texas Instruments doc. sloa101b.pdf

 

[G+_Sean Miller]

For Sensors/Actuators around the home, 1Mbps is a perfectly good bitrate. 40 meters will reach from one corner of my house, up the wall, and over to the other corner. 30 devices max might be the only real limitation. It sounds like a lot for starters....but once you start down that path...they fill up quick.

[G+_Rud Dog]

Sean Miller what about having multiple CAN busses? Wonder what means could attach to the bus to allow cross bus communication?

[G+_Rud Dog]

Chris Eckeard The upside the wires would be low voltage, correct?

[G+_Black Merc]

Rud Dog (thinking outloud) most cars are 12v systems

High voltage wiring is 50v and higher.

[G+_Chris Eckeard (StMerlin]

Rud Dog yes low voltage, 5v and 3.3v with stepped down resistors on one channel.

[G+_Brent Vrieze]

Just a security point. CAN bus does not authenticate the message. If I send a signal to device lets day 4 it accepts it. So then someone else could send a message with malicious intent to device 4, and it will accept it.

 

On a segregated home system that is custom build probably not a huge problem but the insecurity is there.

 

I believe one of the TWIT shows discussed this not long ago. I think it was TWIET.

[G+_Rud Dog]

Looks like someone thought of this well before I did.

hackster.io - Hackster.io

[G+_Ben Reese]

I really like the setup SuperHouseTV has done!

 

He's using Cat-5 or Cat-6 - not for ethernet, but with the opportunity to change to ethernet later.