I want to use a small 8 bit microcontroller which has only a single CAN rx/tx, i.e. Atmel 32c1, but in my application I need to be able to send and receive requests from two CAN buses.
I have read the datasheet for a particular transceiver, AMIS−42700 (http://www.onsemi.com/pub/Collateral/AMIS-42700-D.PDF), but I don't understand whether this physically joins the two buses or allows a microcontroller to receive and send on the two buses, like a mux.
I absolutely don't want the two buses joined for any other devices.
Is this possible by either using a transceiver or multiplexer? I feel the ideal solution would look something like a device which intelligently joins the two buses coming into the microcontroller and has a (perhaps gpio driven) mux on TX which I can change between writing messages to the two different buses to select a bus for writing.