>I have a several (aprox 10-15) small secondary devices that need to
>communicate a small amount (aprox 2 bytes) of information to a central
>controller, and the controller needs to be able to issue instructions to
>the secondary devices individually or as a group.

>Is I2C the best, or some other simple 2 wire solution?

Maybe RS485 and it will work over 1000 M on a single twisted pair........

Cheers Steve.....