AVR-Chat

I've been following this thread, which started as a simple question about the safe current carrying capacity of input protection diodes and morphed into tales of lightning strikes damaging equipment, but now I have a question about the turn it is taking.

TIA/EIA-485 was designed from the outset to operate over long distances and transceivers are generally designed to be robust in the presence of the kind of interference and induced high voltages that are common in long distance data transmission.  When used with the UART that just about every microcontroller has and a simple master / slave protocol (especially where the choice of a master node is "obvious"), the system is simple, reliable and easy to monitor and "debug".

CAN was designed for communication on a network within a vehicle.  Although it is eaily adaptable to room or even small building distances, there is nothing about it that makes it suitable for long outdoor runs.  Transceivers expect to be exposed to interference, but not induced high voltages.  The physical layer protocol is complicated and finicky to set up and you either have to buy or make some kind of sniffer to monitor bus traffic.

So, whence the enthusiasm for CAN on this project?

Graham.